taxonID	type	description	language	source
D14B87DD0007FF80FC50FEC8FA08FA44.taxon	type_taxon	Type genus: Archaehierax gen. nov.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0007FF80FC50FEC8FA08FA44.taxon	discussion	Remarks The fossil is identified as an accipitrid due to the following combination of characters: Skull – Rostrum deep and narrow, with hooked tip and a large, broad nasal aperture; Tibiotarsus – Pons supratendineus ossified, aligned steeply transversely, medially placed, with unbranched canalis tendinosus, and distal condyles much wider than craniocaudally deep; Tarsometatarsus – Robust, with monosulcate hypotarsus, the lateral and medial hypotarsal crests widely separated and trochleae metatarsorum splayed both medially and laterally, and dorsally arched in distal view; Foot – Four digits with raptorial unguals, those of digits 1 and 2 relatively large; Digit IV – phalanges 2 and 3 are very short compared to phalanx 4. Thefossilcanbeexcludedfrom Falconiformes (Falconidae) and the other families of Accipitriformes (Cathartidae, Sagittariidae, Pandionidae) by the morphology of the tarsometatarsal hypotarsus cristae and sulcus. The cristae are fused or partially fused together to enclose thesulcus in Cathartidae, Sagittariidae, and Pandionidae, while in Falconidae the medial crista isconnected to the shaft by a ridge that extends two-thirds of its length, features that are absent in the fossil.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0007FF80FC50FEC8FA08FA44.taxon	diagnosis	Diagnosis Accipitrids in which the following autapomorphic features are found: the pila medialis of the sternum dorsally separates two deep pneumatic fossae, the humerus has the caput humeri only slightly elevated proximally past the tuberculum ventralis, the tip of the processus procoracoideus of the coracoid sharply curves inwards ventrally towards the medial face of the bone, the tibiotarsus has the lateral / distal retinaculum scar in a deep fossa, the tarsometatarsus is relatively elongate with narrow trochleae metatarsorum that are separated by wide incisurae, and the incisura for the m. flexor hallucis brevis tendon is large, distinct, and extends distal to the fossa metatarsi I. In addition to this, the following features occur: the rostral tip of the rostrum is hooked below the tomial margin at a relatively shallow 30 – 40 ° angle, the quadrate has a deep, distinct foramen pneumaticum caudomediale, and the sternum has the apex carinae displaced caudally from the base of the spina externa.,	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0007FF81FCF8F9F3FDD9FD69.taxon	type_taxon	Type species: Archaehierax sylvestris sp. nov.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0007FF81FCF8F9F3FDD9FD69.taxon	description	http: // zoobank. org / urn: lsid: zoobank. org: act: 8 C 4 B 01 F 2 - 12 CE- 46 F 4 - A 444 - C 63 B 18 C 90 BAE	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0007FF81FCF8F9F3FDD9FD69.taxon	etymology	Etymology Archaehierax is derived from the Greek words ‘ archaios’, meaning ancient, and ‘ hierax’, meaning hawk. Gender masculine.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0007FF81FCF8F9F3FDD9FD69.taxon	diagnosis	Diagnosis An accipitrid distinguished by the combination of the following features; Rostrum. (1) The nares are large and fully open, (2) processus maxillopalatini not fused; Quadrate. (3) the condylus pterygoideus projects less medially than the condylus medialis, (4) a deep, distinct fossa caudomedialis with a small amount of pneumatism; Sternum. (5) The apex carinae is displaced caudally from the base of the spina externa, (6) the medial crista on the carina does not extend to the spina externa; (7) The pila medialis on the dorsal face separates two deep fossae (autapomorphy); Humerus. (8) The caput humeri is only slightly elevated proximally past the tuberculum ventralis (autapomorphy); Os carpale ulnare. (9) Deepened depression on ulnaris face; Tarsometatarsus. (10) The trochleae metatarsorum are splayed and separated by wide incisurae, especially laterally, with the individual trochleae themselves quite narrow in width (autapomorphy); (11) The incisura for the m. flexor hallucis brevis tendon is large, distinct, and extends distal to the fossa metatarsi I (autapomorphy); Phalanx IV. 4. (12) The distal articular end that articulates with phalanx IV. 5, is considerably wider than the shaft.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0007FF81FCF8F9F3FDD9FD69.taxon	materials_examined	Type Locality / Stratigraphy / Age 31 ° 07.499 ʹ S; 140 ° 12.755 ʹ E. Site 12 a, Lake Pinpa, Frome Downs Station, Callabonna Sub-Basin, S. A. Dolomite bed of Namba Formation, Pinpa LF, late Oligocene, 26 – 24 Ma.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	description	(Figures 3 - 10)	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	description	http: // zoobank. org / urn: lsid: zoobank. org: act: 092140 CA-E 93743 B 3 - B 3 F 1 - 7127 C 97094 F 4	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	materials_examined	Holotype SAMA P. 54998, 63 elements and associated fragments of a single skeleton (see Figure 2) as follows:	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	description	Fragments of mandible; rostral majority of rostrum; R pterygoid; L quadratojugal; L quadrate; ceratohyal; atlas vertebra; axis vertebra; partial cervical vertebra # 3; caudal vertebrae x 3 (position in tail indeterminate); cranial part sternum; LR scapulae; cranial and sternal parts LR coracoids; proximal LR humeri; Land distal R ulna; Land distal R radius; L carpometacarpus; LR os carpi ulnare; Los carpi radiale; Rmanual phalanges, proximal fragment MI. 1, proximal fragment MII. 1 and MII. 2; Lmanual phalanges MI. 1, MII. 2 with distal end eroded, and MIII. 1; LR proximal femur fragments; Rtibiotarsus reconstructed in two parts; L tibiotarsus; fragmented LR fibulae; LR tarsometatarsi; LR ossa metatarsalia; pedal phalanges: RI. 1, RII. 1, RII. 2, RIII. 1, RIII. 2, RIII. 3 (partial), RIII. 4, LI. 1, LI. 2 (fragmented), LII. 1, LII. 2, LIII. 1, LIII. 2, LIII. 3 (partial), LIII. 4, LIV. 1, LIV. 2, LIV. 3, LIV. 4, LIV. 5. The skeleton was found eroding out on the surface with surviving elements recovered in a semi-articulated state from within dolomitic clays (equivalent to layer 5 of Thorn et al. 2021), with most large elements fractured into many roughly articulated pieces, presumably by expansion and contraction associated with the wetting and drying of the clays. The fragments for each element were, where possible, separated, cleaned and reassembled by THW. Measurements (mm) See Appendix 1 Table S 1.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	etymology	Etymology The species name ‘ sylvestris’ is derived fromthe Greek world ‘ sylvas’, meaning forest, and the Latin suffix ‘ - estris’, meaning ‘ belonging to’.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	materials_examined	Type locality / Stratigraphy and age As per genus.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	diagnosis	Diagnosis As for genus.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	description	Descriptions Rostrum maxillare (Figure 3 (A, B )). The rostral section of the rostrum maxillare is preserved in reasonably good condition. Morphology of its rostral tip, tomial margin, rostral marginof the nares, and the palatines is visible. The rostrum has a preserved length of 32.6 mm from the rostral tip to the posterior base of the nares, and a preserved depth of 17.3 mm from the tomial margin to the dorsal side of the rostrum taken at the rostral end of the nares. (Trait 1) The rostral tip of the rostrum is hooked, descending below the tomial margin at a 30 – 40 ° angle. (2) The lateral tomial margin (Figure 3 A: CT), positioned distal to the nares, is ventrally convex. (3) The nasal aperture (Figure 3 A: N) is large (height 8.7 mm) and fully open as in most accipitrids, spanning just over half the rostrum depth. (4) The ossified section rostral to the incisura ventromedialis is of small to moderate size (10.1 mm preserved length) relative to the total length of the rostrum. (5) In ventral aspect, an incisura ventromedialis (Figure 3 B: IV) (sensu Livezey and Zusi 2007) is present (sediment filled) extending from where damage destroys it rostrally to the preserved caudal end of the palate; it is narrow and widens caudally, rather than being closed forming a fenestra. The pars maxillaris palatini (Figure 3 B: PM) are unfused and diverge slightly caudally, the left being least fragmented although it has broken fromthe adjacent lateral margin creating a false incision. Asmall fragment of bone preserved between the pars maxillaris palatini is interpreted as a displaced fragment of the processus maxillopalatinus. (6) Damage precludes ascertaining the presence / form of the fenestra ventrolaterale. Other accipitrid subfamilies differ as follows: (Trait 1) Compared to the fossil, the tip of the rostrum is much more sharply hooked ventrally in most subfamilies. Only members of Elaninae, Perninae (except Chondrohierax uncinatus, which is sharper), Buteoninae, and Gypaetinae have similar or shallower angled tips. The rostrum maxillare is overall most similarto that of species of Buteoninae (see SI. 2 for more detailed differential comparisons). Quadrate (Figure 3 (C, D )) The left quadrate has considerable breakage affecting the lateral side ventrally, the medial side of the processus oticus, and loss of the processus orbitalis. Preservation of morphological detail isbest medially. On the processus oticus, only about half of the capitulum squamosum is preserved and the dorsal half of the crista medialis is lost. Of the processus orbitalis, only the well-preserved base remains. Both thecondylus pterygoideus and medialisare intact, butthe entire condylus lateralis and caudal half of the condylus caudalis are lost. (Trait 1) The processus oticus (Figure 3 D: POt) is short and broad leading up to the capitulum squamosum. (2) The capitulum squamosum (Figure 3 D: CS), as preserved is relatively small, and has a tuberculum subcapitulare forming a distinct hook projecting ventrally on its cranial margin. (3) The processus orbitalis (Figure 3 C: POr) is dorsomedially oriented. (4) The processus is set entirely in the ventral half of the quadrate, creating a gentle, shallow sloping arc between the base of the processus and the capitulum. (5) Alarge and deep foramen pneumaticum basiorbitale (Figure 3 C: FPB) is present between the processus orbitalis and the condylus pterygoideus. (6) Breakage prohibits assessing the status of the foramen rostromediale. (7) The ventral section of the crista medialis is preserved and is quite broad and flat with no projecting ridge. (8) A thin, distinct sulcusruns along the ventral margin of the crista to connect to the foramen pneumaticum caudomediale. (9) A distinct, deep foramen pneumaticum caudomediale (Figure 3 C: FPC) is present just medial of the ventral-most point of the crista medialis. (10) The condylus pterygoideus (Figure 3 D: CP) is distinct, high-set and well separated from the condylus medialis. (11) The condylus medialis (Figure 3 C: CM) is well preserved, showing a large (4.0 mm wide by 2.8 mm deep), semi-ovular facet, with a pointed medial margin that extends further medially than the condylus pterygoideus. (12) The portion of the condylus caudalis (Figure 3 C: CC) preserved indicates a facet of a similar size to the condylus medialis, with a semicircular shape. Other accipitrid subfamilies differ as follows (variable characters excluded): (Trait 8) The sulcus running along the ventral crista is broad and indistinct in all other taxa except in species of Milvus and Haliaeetus (Haliaeetinae) where it is narrow and indistinct. (9) The fossa caudomediale is practically absent in the subfamilies Circaetinae and Aegypiinae, as well as the species in Hamirostra, Lophoictinia (Perninae), Neophron (Gypaetinae), and Haliaeetus (Haliaeetinae); shallow in Aquilinae and species of Elanoides, Chondrohierax (Perninae), Polyboroides and Gypohierax (Gypaetinae); and deep in Elaninae, Accipitrinae and Buteoninae, as well as species in Pernis (Perninae). The depressio was indistinctly shaped (i. e. a gradually deepened area rather than a defined pit) in all species, and apneumatic in all species except in Pernis and Haliaeetus. The quadrate is overall most similar to that of species of Aegypiinae (see SI. 2 for more detailed differential comparisons). Vertebrae (Figure 3 E - J) The atlas vertebra of SAMA P. 54998 is 10.7 mm wide by 10.7 mm high (from the proximal margin of arcus atlantis to the distal margin of fossa condyloidea). (Trait 1) The arcus atlantis (Figure 3 G: Arc. At.) forms a low, flat arch, which dorsally has a maximum proximodistal width of 3.2 mm at the centre, overhanging the fossa condyloidea cranially. (2) The incisura fossae (Figure 3 G: IF) is shallow and broad, forming a semicircular shape in cranial aspect. (3) The fossa condyloidea (Figure 3 G: FC) is 4.3 mm wide by 4.2 mm long. (4) The dorsolateral eminences of the fossa condyloidea are small. (5) The ventral margin of the fossa forms a rounded point in cranial aspect and is prominent cranially in lateral aspect. (6) The zygopophyses caudales are badly worn and difficult to assess, but what is preserved indicates they were distinct and caudally projected from the rest of the arcus atlantis. (7) The incisurae caudales arcus (Figure 3 E: IAC) are very shallow. (8) The facies articularis axialis (Figure 3 E: FAA) is 5.7 mm wide by approximately 3.8 mm long. (9) The rest of the distal corpus atlantis is worn away and cannot be assessed, but what is present suggests that few additional structures were present, and that there was some asymmetry in the shape of the lateral fossa condyloidea. The axis vertebra is quite fragmented, with most of the neural spine, facies articularis atlantica, dens, facies articularis caudalis, processus ventralis and the area of incisurae caudales arcus broken away. Its width is 12.7 mm across the processus articulares caudales and mid-line length of the corpus vertebra is 8 mm. The facies articularis on zygopophyses caudales are 3.1 mm wide by 3.8 – 4.1 mm long. (10) Ashort but caudally prominent projection is present dorsal to each facet (Figure 3 H: FA), measuring 2 – 2.5 mm in width. (11) There is no evidence of a bridge enclosing the incisurae caudales arcus (Figure 3 F, H: PAC). The three known caudal vertebrae are too broken to identify their position in the caudal series. The vertebrae are overall most similar to that of species of Elaninae (see SI. 2 for more detailed differential comparisons). Sternum (Figure 4 (A, B, C )) The cranial section of the sternum of SAMA P. 54998 is preserved, retaining the structure of the spina externa, pila carinae, crista medialis carinae, apex carinae, the left sulcus articularis coracoideus, and the left labrum internum. It is characterised by: (Trait 1) Aspina interna is absent; a small notch exists in its place. (2) The spina externa (Figure 4 B: SE) is 6.4 mm wide at its base, 4.7 mm wide at its blunt tip and 4.2 mm long. In cranial view, the spina externa is triangular as a medial crista forming a lobe projecting 3.6 mm ventrally. The base of the spina externa is broader than the apex carinae (4.0 mm). (3) The crista medialis carinae (Figure 4 A: CMC) is short, extending dorsally from the apex carinae to mid-height of the pila carinae with a low profile in lateral view. More dorsad, the pila carinae is smooth to the base of the spina externa. (4) The pila carinae (Figure 4 A: PC) is robust for its size, measuring 5.2 mm at mid-depth. It is 23.3 mm long from the ventral margin of the carina sterni to where the pila carinae meets the spina externa. (5) The apex carinae (Figure 4 A: AC) at 4.0 mm wide, is noticeably expanded from the width of the pila carinae immediately dorsal to it (3.0). (6) The apex carinae is rounded, with no hooked projection extending cranially. (7) The maximum carina depth below the sternal basin is roughly equivalent to basin depth below the costal margin, typical of most accipitrids except for certain vulture species (Aegypiinae). (8) The apex carinae is set well caudally [assuming the junction of the carina with the pars cardiaca is aligned horizontally] from the base of the spina externa. (9) There are no small, dispersed pneumatic foramina present dorsally in the body of the sternum. (10) The small part of the carina sterni preserved narrows caudally from the pila carinae. (11) The left sulcus articularis coracoideus (Figure 4 B: SAC) is 4.3 mm dorsoventrally deep, and extends to the midline of the sternum, directly dorsal to the spina externa, where it does not overlap the right sulcus. (12) The left labrum internum (Figure 4 A: LI) is maximally 4.2 mm deep and 2.8 mm wide in dorsal view as preserved. (13) Apila medialis (Figure 4 C: PM), 2.1 mm wide, on the dorsal face of the sternum separates two deep, pneumatic fossae in the pars cardiaca. Extant accipitrid subfamilies differ as follows: (3) The crista medialis extends to the base of the spina externa in membersof allsubfamilies except Aegypiinae. (8) Theapex carinaelies directly ventral to the base of the spina externa, or projects more craniad, in species in all subfamilies except for Gypaetinae and Aegypiinae. (11) The sulci articularis coracoidei overlap in all species except for Gampsonyx swainsonii (Elaninae) and Sarcogyps calvus (Aegypiinae). (13) No species in any subfamily has a distinct pila medialis separating pneumatic fossae in the pars cardiaca, which is thus an autapomorphy suggesting subfamilial distinction for the new species. The sternum is overall most similar to that of species of Aegypiinae (see SI. 2 for more detailed differential comparisons). Coracoid (Figure 4 (F, G, H, I )) The well-preserved left and right omal ends and fragments of both sternal ends of the coracoids of SAMA P. 54998 were recovered. They reveal the following: (Trait 1) Aforamen nervi supracoracoidei (Figure 4 G: FoNS) is present and located adjacent to the shaft rather than near the medial margin of the processus procoracoideus; (2) The foramen lacks an opening into the corpus; and (3) it is small, about 1 mm in width, and positioned just sternal of the cotyla scapularis. (4) Alarge (6 mm wide) pneumatic foramen is present in the sulcus m. supracoracoidei (Figure 4 F: SMS). The width of the sulcus is approximately 14.5 mm fromthe ventrosternal corner of the facies articularis clavicularis to the facies articularis humeralis, and 12.8 mm from the medial margin to the laterodorsal margin immediately cranial to the cotyla scapularis. (5) The facies articularis clavicularis (Figure 4 F: FAC) is large, broad, and clearly delineated sternally by a crista that dorsally overhangs the aforementioned foramen, and ventrally is a low non-overhanging crista. The sternal margin of this facet is straight with no notch nor dorsal or ventral projections directed sternally. (6) The cotyla scapularis (Figure 4 G: CtS), preserved on the right omal fragment, is deep and large (6.7 mm wide by 5.7 mm long) in relation to the processus procoracoideus and triangular shaped. (7) The facies articularis humeralis (Figure 4 G: FAH) is 7.7 mm wide and 12.8 mm long. (8) The impressio lig. acrocoracohumeralis (Figure 4 H: ILA), best seen on the left specimen, forms a distinct sulcus ~ 7 mm wide by 18.1 mm long on the processus acrocoracoideus, although this may be exaggerated by damage to the fossil. (9) The processus procoracoideus (Figure 4 I: P. Procor.) forms a short projection medially, barely as long again as the cotyla scapularis width, with its tip sharply angling ventrally towards the medial face to partly enclose the triosseal canal. (10) The best preserved sternal-end fragment shows that the angulus medialis is acute, forming a 30 – 45 ° angle. (11) The medial side of the facies articularis sternalis is 6.5 mm wide at its broadest point, and shallow, with little deepening towards the dorsal margin. Extant accipitrid subfamilies differ as follows: (Trait 5) The sternal margin of the facies articularis clavicularis does not form a crest overhanging the sulcus supracoracoideus in Elaninae, Perninae (except Chondrohierax uncinatus), Gypaetinae (except Polyboroides typus), Aegypiinae, Haliaeetinae, Accipitrinae, and Buteoninae. (8) The impressio lig. acrocoracohumeralis is shallow in Elaninae, Perninae, Gypaetinae, Accipitrinae, and Buteoninae. (9) In all subfamilies, the processus procoracoideus does not, or barely, angles ventrally towards the medial face. The coracoid is overall most similar to that of species of Aegypiinae, Accipitrinae and Buteoninae (see SI. 2 for more detailed differential comparisons). Scapula (Figure 4 (D, E )) Both the left and right scapulae of Archaehierax sylvestris gen. et. sp. nov. are almost complete, lacking only the distal third or less of the corpus scapulae. In total, the preserved craniocaudal length of the scapulae is 56.8 mm (left) and 53.3 mm (right). The proximal dorsoventral width of the scapula is 14.4 mm from the acromion to the ventral side of the facies articularis humeralis. (1) The tuberculum coracoideum (Figure 4 E: TC) is low and barely cranially prominent dorsal of the facies articularis humeralis. (2) The acromion (Figure 4 D: Ac) has a distinct cranio-laterally oriented crista lig. acrocoracoacromiali dorsally, and a robust rounded medial prominence. (3) There are no pneumatic foramina or fossae present in the acromion cranially, (4) nor on the lateral or medial facies between the acromion and the facies articularis humeralis. (5) The facies articularis humeralis (Figure 4 D: FAH) is quite large and broad, measuring 6.3 mm dorsoventrally by 10.8 mm craniocaudally on the left specimen; 6.3 mm by 10.4 mm on the right. (6) The acromion barely projects proximally / cranially of the tuberculum coracoideum. (7) Minimum dorsoventral depth of the collum scapulae (Figure 4 E: ColS) is 6.3 mm. (8) While the extremitas caudalis is broken off, the corpus scapulae is elongate and moderately narrow, (9) but it greatly increases in depth caudal to the margo dorsalis ridge (Figure 4 D: MD), attaining a maximum dorsoventral depth of 8.1 mm. (10) The lateral face dorsal to and immediately posterior to the facies articularis humeralis is flat. (11) The ligamental attachment on the margo dorsalis has a very small prominence and is not elevated dorsally above the rest of the margo dorsalis. Extant accipitrid subfamilies differ as follows: (Trait 6) The acromion strongly projects cranially in all species except in pernines (Chondrohierax uncinatus, Pernis apivorus, Aviceda subcristata), and Ictinia mississippiensis (Buteoninae). The scapula is overall most similar to that of species of Elaninae (see SI. 2 for more detailed differential comparisons). Humerus (Figure 5). The humeri are poorly preserved in SAMA P. 54998. Only the caput humeri, crus dorsale fossae, fossa pneumotricipitalis, and the incisura capitis of the proximal end of the right humerus is preserved. The left humerus is more complete, preserving about 60 mm of proximodistal length of the proximal end including the caput humeri, crus dorsale fossae, fossa pneumotricipitalis, incisura capitis, sulcus lig. transversus, facies bicipitalis, crista deltopectoralis, and some of the proximal shaft. However, there is also significant breakage and fracturing of the bone surface in this specimen, which has resulted in the loss of the tuberculum dorsale, the ventral marginof the crista bicipitalis, tuberculum ventrale, and sulcus n. coracobrachialis. These specimens reveal the following: (1) The incisura capitis (Figure 5 A: IC), as best observed in the left humerus, is shallow and lacks secondary deepening. (2) There is no visible ligamental scar in the distal incisura capitis. (3) The caput humeri (Figure 5 A: CH) is quite flattened, projecting proximal to the incisura capitis only a few millimetres. (4) The fossa pneumotricipitalis (Figure 5 A: FP) was large and deep, although breakage precludes assessing its former width. The betterpreserved left specimen shows it was minimally 7.7 mm wide. (5) The crus dorsale fossae (Figure 5 A: CDF) is broad, measuring 4.0 mm wide, and is caudally convex. (6) The sulcus lig. transversus (Figure 5 C: SLT), best seen in the left humerus, is shallow but well defined, and seems continuous between the ventral and dorsal sections. Ventrally, the sulcus is deep and round, measuring 6.3 mm wide by 4.5 mm long cranial to the incisura capitis. The crista deltopectoralis (Figure 5 B: CrD), while quite fractured, is preserved in its entirety in the left specimen. Preserved length is 42.7 mm from the assumed position of the tuberculum dorsale to its distal end. (7) The profile of the proximal section of the dorsal margin of the crista between its origin near the tuberculum dorsale and the angulus cristae of the crista deltopectoralis is flat in a ventro-cranial view. (8) The angulus cristae of the crista deltopectoralis is very prominent and distinctly triangular in dorsal view. (9) Distally, the crista deltopectoralis, while fractured, projected mainly cranially (shaft margin visible proximal to the distal point of crista). Extant accipitrid subfamilies differ as follows: (Trait 1) In all subfamilies except Aegypiinae and Spilornis cheela in Circaetinae, species have a deep incisura capitis; (3) The caput humeri is more elevated proximal to the incisura capitis and tuberculum ventrale, ranging from a moderate (Elaninae) to a large proximal projection (all other subfamilies) so a low flattened caput is identified as an autapomorphy of the species. The proximal humerus is overall most similar to that of species of Elaninae, Aegypiinae, Aquilinae, Haliaeetinae and Buteoninae (see SI. 2 for more detailed differential comparisons). Ulna (Figure 6 (C, D, E )) SAMA P. 54998 preserves a near-complete left ulna, reassembled from fragments, that is only missing the olecranon, parts of the ventral margin of the cotyla ventralis contiguous with the olecranon, and the caudodorsal margin of the cotyla dorsalis. The distal right ulna is also preserved with the condyles mostly intact, with only the ventrocaudal margin of the condylus dorsalis and condylus ventralis worn away. They reveal the following features: (1) The ulna is largely straight in dorsal and ventral view, with only very slight caudal curvature towards the proximal and distal ends. The processus cotylaris dorsalis projects distally of the cotyla ventralis (Figure 6 E: PCD), is 5.8 mm wide, and (2) is quadrangular in shape with a flattened dorsal tip between parallel equal-length proximodorsal and distoventral sides. (3) The cotylae are shallow, separating by a moderately proximally protruding crista intercotylaris (Figure 6 D: CrI). Breakage precludes assessing if a pneumatic fossa or foramen was present caudal of the cotylaris dorsalis. (4) The impressio scapulotricipitis (Figure 6 E: IST) is shallow. (5) The incisura radialis (Figure 6 D: IR), defined by the margin of the cotyla ventralis proximoventrally, the tuberculum cranialis distally, and a ridge descendingventrodistally fromthe base of the processus cotylaris dorsalis dorsally, is shallow. (6) Distal to the incisura radialis two tubercula are present, one on the cranial face is large and round (3.8 mm wide) and distinctly projects from the shaft (Figure 6 D, E: T), the other smaller (1.9 mm wide) and flatter positioned adjacent to it on the ventral face. (7) The impressio brachialis (Figure 6 C: IB) is shallow, with the base flat and not depressed relative to the shaft and is 12 mm long proximodistally. The midshaft of the left specimen is 7.7 mm craniocaudally wide in dorsal aspect. (8) The papillae remigales caudales form low, barely prominent scars, which is typical of most accipitrids. The distal end of the ulna measures 12.9 mm wide (left) and 12.2 mm wide (right) between the cranial point of the tuberculum carpale (Figure 6 C: TCr) and the caudal margin of the condylus dorsalis (Figure 6 C: CD) in ventral aspect. (9) The tuberculum carpale is short and blunt, or rounded, in dorsal and ventral view, (10) with a flattened facet directed ventrodistally. (11) The incisura tuberculum carpale (Figure 6 C: ITC) forms a distinct notch separating the tuberculum carpale and condylus ventralis (Figure 6 C: CV) when viewed in dorsal aspect. The condylus dorsalis (left specimen) is 13.5 mm long proximodistally along its caudal margin in ventral aspect, and 9.3 mm deep fromthe caudal margin to the incisura tendinosa, in caudodorsal view. (12) The caudal marginof the condylus dorsalis forms a continuous curve in the proximal half, best visible in either craniodorsal or caudodorsal view, interrupted only by a small notch for the incisura tendinosa (Figure 6 E: IT). (13) The incisura tendinosa lies between the condylus dorsalis and the condylus ventralis (dorsal aspect), though it does not quite separate the two proximodistally. (14) The depressio radialis (Figure 6 C: DR) is shallow and not pneumatized. (15) The sulcus intercondylaris (Figure 6 C: SI) forms a relatively deep v-shape in ventral aspect. (16) The condylus ventralis distinctly projects distocranially, and measures 5.7 mm wide (in ventral aspect) by 11.2 mm deep (in cranial aspect). Extant accipitrid subfamilies differ as follows: (Trait 1) The proximal shaft is notably curved cranially in elanines, most pernines (except Aviceda subcristata, Lophoictinia isura and Hamirostra melanosternon), and buteonines (except species of Circus). The ulna is overall most similar to that of species of Circaetinae (see SI. 2 for more detailed differential comparisons). Radius (Figure 6 (A, B )) In SAMA P. 54998, the left radius is complete, preserving most features of the proximal (cotyla humeralis slightly worn ventrocaudally) and distal ends. The cotyla humeralis is large, measuring 5.5 mm deep dorsoventrally, and 4.1 mm wide. It shows the following: Atuberculum bicipitale radiale (Figure 6 A: TBR) is located 5.4 mm distal of the facies articularis ulnaris on the dorsal face. The tuberculum has (1) a large, deep, non-pneumatic fossa (2.6 mm wide by 3.8 mm proximodistal length) on it, and (2) has a distinct profile in cranial view as a low, quadrangular ridge. (3) The sulcus tendineus (Figure 6 B: ST) is very shallow, barely differentiated from the corpus. (5) The tuberculum aponeurosis ventralis (Figure 6 A: TAV) projects ventrally at approximately 60 – 70 °, and its tip is rounded. (6) The facies articularis radiocarpalis (Figure 6 A: FAR) is quite flat in dorsal view, but slightly curves out distally from the tuberculum aponeurosis ventralis to the opposite margin. (7) The depressio ligamentosa (Figure 6 A: DL) on the ventral face of the distal end is deep but lacks pneumatism. (8) The facies articularis ulnaris (Figure 6 (A, B): FAU) forms a prominent bulb that projects out ventrally, and which has a deep notch on the proximal margin that gives it a doublepeaked appearance. Extant accipitrid subfamilies differ as follows: (Trait 1) The fossa associated with the tuberculum bicipitalis is shallow in all species except some pernines e. g., Elanoides forficatus (absent) and Pernis apivorus (deep). (5) The tuberculum aponeurosis ventralis projects at a more abrupt angle in all taxa except N. percnopterus (Gypaetinae), species of Gyps (Aegypiinae), and H. morphnoides and A. chrysaetos (Aquilinae). (7) The depressio ligamentosa is shallower in Perninae (except E. forficatus), Gypaetinae, Circaetinae, Aquilinae, Haliaeetinae, and Buteoninae. The radius is overall most similar to that of species of Haliaeetinae and Gypaetinae (see SI. 2 for more detailed differential comparisons). Os carpale radiale (Figure 7 (G, H )) The left os carpale radiale is complete in SAMA P. 54998. Measurements: proximodistal length 8.6 mm, dorsoventral width 12.3 mm, and depth 5.4 mm. Ithasthefollowing features, terminologyfrom Mayr (2014): (1) The distoventralprojection (Figure 7 G: DVP) issmalland pointed, oriented at an angle between 45 ° and 60 °. (2) The notch for the musculus ulnometacarpalis ventralis (Figure 7 H: NMUMV) is distinct, but shallow. (3) The facies articularis metacarpalis (Figure 7 H: FAM) slightly projects distally from the cranial face in cranial view. (4) The sulcus for the musculus extensor carpi radialis (Figure 7 H: ECR) is shallow, forming a gentle curve at about a 160 ° angle between the ventral and dorsal ends. (5) A broad, deep fossa covers most of the ventral half of the cranial face (Figure 7 H: CVFos), which is open towards the proximo-ventral corner. (6) Asecond smaller and deep fossa is present on the dorsal half of the cranial face (Figure 7 H: DVF), and is apneumatic and oriented more craniodorsally. (7) The facies articularis radialis (Figure 7 G: FARad) is broad (depth ~ 5.7 mm, dorsoventral width 11.0 mm) and strongly marked on the caudal face. (8) The caudal face has a small but deep fossa (Figure 7 G: FAUF), set in the facies articularis ulnaris (Figure 7 G: FAU) close towards the ventral end. (9) The caudalmargin of the faciesarticularis metacarpalis formsa convex continuous curve from the ventral margin to the dorsal margin. The os carpale radiale is overall most similar to that of species of Elaninae and Buteoninae (see SI. 2 for more detailed differential comparisons). Os carpale ulnare (Figure 7 (I, J )) Both the right and left os carpale ulnare are complete in SAMA P. 54998. Measurements (mm) right / left: dorsoventral width 12.2 / 11.8, craniocaudal depth (excluding cranial projection) 4.4 / 4.6, and proximodistal length 9.9 / 9.2. They show: (1) Adistinct projection, roughly in the centre of the cranial face (Figure 7 J: CrPro), extends well cranially above the margin of the proximal ligament attachment, and lacks a prominent ridge that makes it contiguous with the proximodorsal corner. (2) The rest of the cranial face is roughly equal in cranial height towards the crus breve (Figure 7 J: CB) and the crus longus (Figure 7 J: CrL). (3) The proximodorsal corner of the crus longus is distinctly notched by a deepened apneumatic fossa (Figure 7 J: PDF). (4) The proximal margin of the cranial face has a distinct ligament attachment point (Figure 7 J: PLA), projecting slightly proximally above the face and positioned ventrally adjacent to the proximal end of the crus longus. (5) The crus breve is slightly shorter (8.7 mm long) in the right specimen, than total length (9.4 mm) from the proximal point of the crus longus to the distal margin, (6) and has a flattened, ventral face. (7) On the caudal face, a very low projection is present on the proximal margin immediately adjacent to the ventral crus breve (Figure 7 I: PVP). (8) A distinct, deep impression is present in the caudal surface (Figure 7 I: CaD). (9) This depression is separated from the rest of the distal face by a distinct but low crista that extends dorsoventrally across the face from the caudal projection (Figure 7 I: CCr), connecting to both the crus breve and crus longus. (10) The incisura metacarpalis is deep and broadly v-shaped (Figure 7 J: IM), with the peak offset towards the crus breve. (11) Avery shallow sulcus is seen running along the proximodistal extent of the caudal face of the crus longus (Figure 7 I: CLS), (12) which terminates in a shallow fossa on the distal point of the crus (Figure 7 I: CLF). Extant accipitrid subfamilies differ as follows: (Trait 2) The ventral cranial face is higher set cranially than the dorsalcranial facein allsubfamiliesexcept Accipitrinae. (3) There isno notchontheproximalendof thecruslongusin allsubfamiliesexceptin the genera Aquila (Aquilinae), Haliaeetus (Haliaeetinae) and Buteo (Buteoninae), which have a shallow notch. (8) There is no deepened depression on the caudal face in all subfamilies except Aquilinae, Aegypius monachus (Aegypiinae), Accipitrinae, and the genus Buteo (Buteoninae). (9) There is no raised crista on the caudal face in all subfamilies except in the genus Buteo (Buteoninae). The os carpale ulnare is overall most similar to that of species of Elaninae, Perninae, Gypaetinae and Aquilinae (see SI. 2 for more detailed differential comparisons). Carpometacarpus (Figure 7 (A, B )) For SAMA P. 54998, the left carpometacarpus is almost complete, missing only the cranial section of the facies articularis digitalis majus. (1) The fossa infratrochlearis (Figure 7 A: FI) is deep and lacks pneumatisation. (2) Arounded ridge extending from the processus pisiformis to the trochlear rim separates the fossa infratrochlearis from (3) an extremely deep sulcus (Figure 7 A: SV) between the processus pisiformis and the processus extensorius. This sulcus is elongate and extends from the trochlea carpalis (Figure 7 B: TrC) to adjacent to the processus alularis (Figure 7 B: PA). (4) The fossa supratrochlearis (Figure 7 B: FS), which is caudoventrally positioned on the ventral face of the proximal end, is shallow and lacks pneumatisation. (5) There is a shallow sulcus on the ventral face, on the proximal margin at the base of the processus extensorius just distal to the trochlea carpalis (Figure 7 A: PS). (6) The fovea carpalis cranialis (Figure 7 A: FCCr) is shallow and apneumatic. (7) The fovea carpalis caudalis (Figure 7 B: FCCd) is very shallow and apneumatic. (8) The ventral rim of the trochlea carpale projects strongly caudally and distally is short, terminating slightly distal to the level of the processus pisiformis. (9) The proximal margin of the processus extensorius (Figure 7 A: PE) and the trochlea carpale forms an approximately 120 ° angle, with the proximal margin slightly upturned proximally. From base to tip, the processus extensorius measures 7.7 mm in craniocaudal width, and is 39 % of the 19.6 mm proximal width of the carpometacarpus. (10) The proximodorsal margin of the processus extensorius forms a sharp crista that dorsally overhangs the dorsal face of the processus. (11) The processus alularis protrudes slightly cranially in a triangular bulge, with a single curved articular facet distally. (12) The processus alularis is separated from the caudal surface of the shaft by a small notch on the dorsal face. (13) The processus pisiformis (Figure 7 A: PrPis) strongly projects ventrally in caudal and cranial view, and is positioned central on the ventral face between the processus extensorius and the caudal margin of the trochlea carpalis. It is separated from the spatium intermetacarpale (Figure 7 A: SpI) by a dorsoventral length of 10.5 mm. (14) This region of separation between the processus pisiformis and spatium intermetacarpale is occupied by a shallow sulcus that is bound by the os metacarpale minus in its distal half. (15) The synostosal region distal to the processus alularis is wider craniocaudally than it is long dorsoventrally. (16) The intermetacarpal tuberosity (Figure 7 A: ITR), which is the scar for the insertion of the m. extensor metacarpi ulnaris has almost no caudal projection and is positioned well distal of the proximal synostosis (Figure 7 A: Psyn). (17) The sulcus tendineus (Figure 7 B: ST) is primarily located on the dorsal face of the shaft. (18) The sulcus tendineus is broad. (19) The proximal region of the os metacarpale minus has a distinct groove on the caudal face, which lacks any pneumatisation. (20) The os metacarpale minus (Figure 7 B: OMMi) is slightly arched caudally when viewed in ventral and dorsal aspect. (21) The facies articularis digitalis minor (Figure 7 B: FADMin) projects further distally than the preserved facies articularis digitalis major (Figure 7 A: FADMaj). (22) The length between the distal point of the facies articularis digitalis minor and the spatium intermetacarpale is approximately equal to the width of the spatium. (23) The distal synostosis (Figure 7 A: DSyn) is very short. (24) The os metacarpale majus (Figure 7 A: OMMa) has a markedly flattened cranial face and is dorsoventrally deeper than it is craniocaudally wide. (25) The sulcus interosseus positioned in the distal synostosis is slightly deepened. Measurements – see Appendix 1 Table S 1; overall, the carpometacarpus has a proximal craniocaudal width that is equivalent to 25 % of the total length, which is moderately gracile. Extant accipitrid subfamilies differ as follows (Trait 1) The fossa infratrochlearisis shallow, except in Perninae (deep in Pernis apivorus and Chondrohierax uncinatus, the latter also pneumatic) and Gypaetinae (deep). (19) The proximal section of the os metacarpale minus has a shallower groove, except in P. typus (Gypaetinae, deep) and Haliaeetus leucocephalus (Haliaeetinae, deep), or in Elaninae (flat, ungrooved). The carpometacarpus is overall most similar to that of species of Buteoninae (see SI. 2 for more detailed differential comparisons). Manus (Figure 7 C, D, E, F) The manus bones are moderately well-preserved in SAMA P. 54998, with a mostly intact left phalanx digiti alulae (L MI. 1), complete left phalanx digiti minoris (L MIII. 1) and left phalanx digiti majoris 2 (L MII. 2), and a mostly intact R MI. 1, partial R MII. 1 and fragment of the R MII. 2. (1) The proximal L MI. 1 has a dorsoventral width of 6.6 mm and a craniocaudal depth of 6.5 mm, and from proximal view is triangular. (2) The cranial margin is tapered into a thin crista that continues along the length of the preserved bone. (3) Asmall tuberculum is present on the caudal margin of the ventral face, close to the proximal end. (4) The dorsal margin and face of the proximal end is much more protruding than the ventral margin and face and has two ligament attachment points on its dorsal surface. (5) The width of the bone narrows distally. (6) The L MIII. 1 is 14.2 mm long and has a prominent caudal projection slightly less than halfway distally along its length, the tip of which is oriented caudoproximally. (7) Both the dorsal and ventral face lack any sort of depression or sulcus. Only the proximal end of the MII. 1 is preserved, which is 8.3 mm wide by 6.9 mm deep. (8) The caudal margin projects caudally into a thin crista, and a deep depression is visible just distal of the projecting point. The left MII. 2 is 24.1 mm long and proximally has a dorsoventral height of 5.8 mm and a craniocaudal depth of 4.8 mm. (9) The caudal margin forms a thin crista. (10) The proximal quarter of the cranial margin is also flattened, but then expands notably with the presence a shallow sulcus extending to the distal end. (11) On the dorsal surface, a low ridge is present at the proximal end, with a small but deep fossa set into the caudal side of it. (12) Asimilar fossa is also set into the caudal side of this ridge in proximal view, just distal of the articular facet. (13) The ventral face has a deep depression lacking pneumatic foramina just distal of the proximal end. The manus bones are overall most similar to those of species of Perninae (see SI. 2 for more detailed differential comparisons). Femur (Figure 8 (A, B )) In SAMA P. 54998, only the caput of both femora has been preserved, preserving the articularis acetabularis face and the fovea ligamenti capitis. The width of the caput is 7.6 mm. The fovea ligament capitis (Figure 8 A: FLC) is shallow and set in the proximal margin of the caput. The articularis acetabularis face (Figure 8 B: FAAce) is not well defined from the medial face. Tibiotarsus (Figure 8 (C, D, E, F, G )) Both the right and left tibiotarsi are preserved in SAMA P. 54998. The left tibiotarsus is almost complete with only the proximal articular surfaces missing. It preservesthebase of thecnemial crestsand the entirecrista fibularis, butdamageto thedistal end obscuresthedetails of the pons supratendineus, the tuberculum retinaculum m. fibularis, and the distal insertion scar for the retinaculum extensorium tibiotarsi. The right tibiotarsus is missing the entire proximal end, and the distal end could not be reconnected to the shaft but is very wellpreserved revealing most features of interest. As observed on the left element, (1) the impressio lig. collateralis medialis (Figure 8 C: ILCM) is a slightly elevated tuberculum on the medial face, measuring 4.5 mm wide and 8.9 mm long. (2) The crista fibularis (Figure 8 C: CrF) is approximately 33.3 mm long, or roughly 24 % of the preserved length (135.7 mm). (3) The crista fibularis is prominent, maximally projecting 2.4 mm, or approximately 26 % of shaft width (9.3 mm) at the same point. (4) The width of the crista fibularis is greatest distally. (5) The cranial face directly adjacent to the crista fibularis is slightly convex. (6) The scar for the ligament that connected to the distal end of the fibula is approximately 34.5 mm long and extends distally along the lateral margin of the shaft, from 38 mm distal to the crista fibularis. (7) Adistinct linea is visible on the medial margin of the shaft that extends approximately 77.4 mm proximodistally fromthe distal base of the impressio lig. collateralis medialis. (8) The cross-section of the shaft at mid length is roughly circular. (9) The sulcus extensorius (Figure 8 G: SExt) is medially positioned on the distal third of the shaft and is approximately 5 mm wide at broadest, compared to a shaft width of 10.5 mm at the same section. (10) The lateral margin of the sulcus is bordered by a raised crista (Figure 8 G: SELC). (11) The canalis extensorius (Figure 8 G: CExt) is deep, and both openings are quite large. (12) The pons supratendineus (Figure 8 G: PS) is obliquely angled at roughly 45 ° to the long axis, and (13) is distinctly arched cranially. (14) The distomedial margin of the pons supratendineus lies close (1.3 mm) to the medial shaft margin. (15) The cranial tuberculum retinaculi m. fibularis (Figure 8 G: CrTRMF) is craniolaterally prominent. (16) The caudal tuberculum retinaculi m. fibularis is low and barely projecting, but preservation is poor in this region of the bone. (17) The proximal scar (tuberositas retinaculum extensoris medialis, Figure 8 G: PTREM) is separated proximally from the pons supratendineus by a distance equal to the proximodistal width of the pons. (18) The distal / lateral attachment of the extensor retinaculum (Figure 8: DREM) is marked by a deep, round fossa. (19) Distal width (17.5 mm) is greater than the maximum distal depth (13.4 mm) by roughly 24 % (right element). (20) The increase in width from the shaft to the distal end is gradual and symmetrical either side. (21) The condyles have roughly equal craniocaudal depth in distal view, (22) with a deep incisura intercondylaris roughly 25 % of depth of the distal end, (23) and the impression in the trochlea cartilaginis tibialis in caudal view forms an inverted v-shape. (24) The epicondylus medialis (Figure 8 E: ECM) is large and projects well medial to the condylus medialis, being visible in cranial view, and is of moderate robustness. (25) The epicondyle is surrounded by a deep depressio medialis (Figure 8 E: DEM), which is bordered by a thin but prominent crista on the margins of the condyle. (26) The depressio lateralis (Figure 8 F: DEL) is shallow, and bordered by a flattened, broad crista on the distal margin of the lateral condyle. The trochlea cartilaginis tibialis is difficult to assess due to breakage, (27) but appears largely flat. Extant accipitrid subfamilies differ as follows: The medial side of the pons supratendineus is more widely separated from the medial shaft margin (Trait 14) in elanines, pernines except E. forficatus, gypaetines, aegypiines, circaetines, aquilines, and haliaeetines. (10) There is no crista on the lateral margin of the sulcus extensorius in elanines, gypaetines, aegypiines, circaetines, aquilines, haliaeetines, accipitrines or buteonines. (18) No species in any subfamily has the lateral / distal retinaculum scar in a deep fossa; it ranges from a shallow fossa (pernines, aegypiines, circaetines, aquilines, haliaeetines), to flat (elanines, some pernines, gypaetines), or slightly elevated rugose surface (accipitrines, buteonines), identifying the deep pit for the distolateral insertion of the retinaculum extensoris medialis as an autapomorphy of the fossil. The tibiotarsus is overall most similar to that of species of Buteoninae (see SI. 2 for more detailed differential comparisons). Fibula The proximal ends of the left and right fibulae are preserved in Archaehierax sylvestris gen. et. sp. nov. Craniocaudal depth is about 10.2 mm, while width is 3.7 (right) and 4.0 mm (left). (1) Ashallow fossa is present in the cranial half of the proximal lateral face. (2) The caudal face has a very shallow depression just distal to the caudal projection. (3) The medial face has a broad but shallow sulcus that extends from near the proximal margin down the shaft. Tarsometatarsus (Figure 9) The right and left tarsometatarsi are both imperfectly preserved in SAMA P. 54998. The left tarsometatarsus preserves the original length of the bone, though the medial half and the proximal end, from mid-length on the medial side to and including the area proximal to the foramen vasculare proximale laterale, has been dorsolaterally twisted approximately 90 ° relative to the rest of the bone. The lateral half is thus undistorted from just proximal to the foramen vasculare proximale laterale distally. The cotyla lateralis is missing with about half of the eminentia intercotylaris. The foramen vasculare proximale mediale is obscured by the distortion on both the dorsal and plantar side. The right specimen has the distal half preserved well with all features, but the proximal half is so badly fragmented that nearly all identifying features are lost. Only the crista medialis hypotarsi is recognisable. The specimens reveal the following features: (1) Thelength of the tarsometatarsus is about 66 – 75 % of the length of the tibiotarsus (uncertainty allows for the missing proximal end of the tibiotarsus). (2) The length to distal width (maximal across trochleae) ratio is approximately 1: 6 and shows the tarsometatarsus is moderately elongate among accipitrids. (3) The cotyla medialis (Figure 9 D: CtM) is deep and with a notably convex dorsal margin. (4) The eminentia intercotylaris (Figure 9 D: EI) projects a few millimetres proximally to the rim of the cotyla medialis. (5) The crista lateralis flexoris hallucis longus (sensu Mayr 2016) (lateral hypotarsal crista) and the crista medialis flexoris digitorum longus (medial hypotarsal crista) (Figure 9 E: CMFDL) are not fused together plantarly, and so form a wide monosulcate hypotarsus. (6) The medial hypotarsal crista is distinctly proximodistally longer (8.9 mm from proximal margin to distal hook, 11.4 mm from proximal margin to distal termination point) than the lateral hypotarsal crista (6.0 mm). (7) The plantar depth of the lateral hypotarsal crista is 13.6 mm (76 %) of the depth of the medial hypotarsal crista 17.8 mm. (8) In medial view, themedialhypotarsal cristahaslittle or nohook distally. (9) Thesulcus flexorius (Figure 9 B: SF) is moderately deep, with the cristae plantares lateralis and medialis quite distinct and projecting plantarly. (10) The tuberositas m. cranialis (Figure 9 A: T) is positioned towards the lateral side of the shaft, moderately projects dorsally to the adjacent laterodorsal margin, (11) is short and oval shaped, (12) and is positioned well distal (5.2 mm) of the lateral foramina vascularia proximalia. (13) The impressio retinaculi extensorii, preserved on the dislocated cotyla medialis, are a pairof distinctlyprojecting cristae, withthe retinaculum itself unossified, which is the typical state among the accipitrids. (14) The fossa infracotylaris dorsalis is shallow in the undamaged section distal to the eminentia intercotylaris and towards the retinaculi. (15) There is a distinct sulcus extensorius (Figure 9 A: SExt) at mid-length, which opens to the medial face around two-thirds of the distance distally along the shaft. (16) The medial half of the proximal 40 % of the shaft is highly compressed as it is in many accipitrids, forming a crista 1.3 mm thick. (17) The crista plantaris lateralis (Figure 9 G: CPL) is well-developed, extending from the hypotarsus to level with thefossa metatarsi I. (18) In lateral aspect the cristaplantaris lateralisis markedly projecting plantarly, deepest just proximal to mid-length. (19) The foramen vasculare distale (Figure 9 A: FVD) has a diameter of about 1.6 mm and is positioned close to the incisura intertrochlearis lateralis. (20) The fossametatarsi I (Figure 9 B: FMI) issetlargelyon the plantar face, though partially faces medially, and measures 6.7 mm long by 3.5 mm wide. (21) The incisura m. flexor hallucis brevis (Figure 9 F: IMFHB) is very distinct, passing dorsally above and distal tothe fossa metatarsi I, toopen plantarly between thefacet in metatarsi Iand trochlea metatarsi II. This state of the incisura was rarely seen in our comparative sample, with a similar but shallower incisura in species of Haliaeetus and Harpia harpyja (slightly deeper) that ends just proximal to the fossa metatarsi I. (22) The fossa supratrochlearis plantaris is very shallow. (23) The incisura intertrochlearis medialis (Figure 9 A: IIM) and incisura intertrochlearis lateralis (Figure 9 A: IIL) areextremely wide comparedto in other Accipitridae. (24) From distal view, the trochleae are arched dorsally. All trochleae are higher than they are wide (excluding extension from flanges). (25) The plantar extent of trochleae metatarsorum II (Figure 9 H: TII) and IV are almost identical (9.1 mm and 9.5 mm respectively, measured from right specimen). (26) Trochlea metatarsi III (Figure 9 H: TIII) is located comparatively much higher dorsally, and while it has a depth of 7.7 mm, the plantar-most point of it is separated from that of trochlea metatarsi IV by about 6.6 mm. (27) Trochlea metatarsi II has a robust profileindistal view, with a short, robustplantarprojection on itsouter margin and a deep fovea ligamentosa collateralis. (28) Trochlea metatarsi III has a robust profile in distal view and has a shallow medial groove dorsodistally. (29) Trochlea metatarsi III is laterally directed relative to the shaft axis. (30) Trochlea metatarsi IV is the narrowest of the trochleae in distal view, with a short, thin plantar projection on the lateral margin. (31) The flange on trochlea metatarsi II is moderately projecting plantarly, (32) while the flange on trochlea metatarsi IV is quite prominent and plantar oriented. (33) The distal extent of the trochleae metatarsorum II and III is roughly equal and surpass distally the distal margin of IV. Extant accipitrids differ across all subfamilies as follows: (9) The sulcus flexorius is shallower, with the cristae plantares lateralis and medialis relatively low in elanines, gypaetines, circaetines, haliaeetines, and buteonines. (21) The incisura m. flexor hallucis brevis is shallower and shorter ending at or proximal to the fossa metatarsi Iin all observed species. (23) In all subfamilies, the incisura intertrochleae are relatively narrower and the autapomorphically wide incisura in the fossil is one of its most characteristic features. The tarsometatarsus is overall most similar to that of species of Elaninae (although more elongate), Aquilinae and Circaetinae (see SI. 2 for more detailed differential comparisons). DigitI (Figure 10 A) The os metatarsale Iin SAMA P. 54998 is fairly robust, with the proximal end attenuated to a thin point. In dorsal and plantar view, the region immediately proximal to the medial side of the articular surfacefor I. 1 isinflated, creatinga> 90 ° anglejustdistal of themidlength point along the ‘ shaft’. The attachment facet for the tarsometatarsus is quite long, extending to be adjacent with the previously mentioned inflation, but is not prominent in lateral view. The sulcus for a tendon on the distal dorsal face is bordered by a reduced crest that is positioned slightly medial of centre in the metatarsal. The phalanx I. 1 is long and moderately robust, with the enlarged proximal end much wider than the corpus. Plantarly, the tubercula flexoria are enlarged, enclosing a broad sulcus that extends as a shallowattachment point to roughly midway on the corpusdistally. The lateral side of the face dorsalis of the proximal end is slightly inflated into a ligamental attachment point, forming a modest, rounded mound. The foveae lig. collaterales on the distal end are very deep, and there is only a very shallow indentation set between the two foveae on the dorsal face. The ungual phalanx I. 2 (as seen in right side) is slightly larger than the ungual phalanx II. 3, with mild curvature along the ungual phalanx. The phalanx I. 1 and ungual I. 2 exhibit notable hypertrophy in contrast to digits III and IV, a trait that is present in almost all Accipitridae (Fowler et al. 2009). Digit II (Figure 10 B)	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	discussion	Like most accipitrids, there is no fusion of the phalanges II. 1 and II. 3. The species in Haliaeetinae and Ictinia are notable for such fusion (see Jollie 1976). The phalanx II. 1 is quite short compared to phalanx II. 2, being just under half its length and considerably shortened lengthwise (not compressed lateromedially), which is a common trait in Accipitridae. All phalanges are notably hypertrophied compared to those in digits III and IV.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	description	Digit III (Figure 10 C) Four phalanges are present. The medial face of the ungual phalanx (III. 4) lacks the central ridge present in most accipitrids and falconids, though it is possibly that this feature has been poorly preserved. Digit IV (Figure 10 D)	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0006FF90FFB5FCD9FA73FACE.taxon	discussion	The midshaft width of phalanx IV. 4 is 3.2 mm, compared to the 3.8 mm of phalanx I, and the distal end of phalanx IV. 4 is distinctly widened, measuring 4.6 mm. This dramatic shift in width along the digit does not appear in the sampled elanine genera (Elanus, Gampsonyx), species of Hieraaetus (though the section before the articular end is swollen) or Spizaetus, but appears to a lesser degree in the pernines, gypaetines, circaetines, aegypiines, species of Aquila, and species of Haliaeetus. Summary Archaehierax sylvestris shares a mosaic of characters across a broad range of taxa and thus the above comparisons do not reveal clear affinity with any one taxon. Different elements in the fossil skeleton differ markedly as to which subfamilies they most closely resemble: the rostrum maxillare – buteonines; the quadrate – aegypiines; the vertebrae – elanines; the sternum – aegypiines; the coracoid – aegypiines, accipitrines, and buteonines; the scapula – elanines; the humerus – elanines, aegypiines, aquilines, haliaeetines and buteonines; the ulna – circaetines; the os carpi radiale – elanines and buteonines; the os carpi ulnare - elanines, pernines, gypaetines and aquilines; the carpometacarpus - buteonines; the tibiotarsus – buteonines; and the tarsometatarsus – elanines (fossil is more elongate), aquilines and circaetines. There are several autapomorphies which further differentiate it from all extant subfamilies. Notably these include the sternal basin having a medial bar separating deep pneumatic fossae, humerus with very low proximal projection of the caput, and tarsometatarsus with broad incisurae intertrochleae and the incisura for the m. flexor hallucis brevis tendon extending distal to the fossa metatarsi I. Together, these support differentiation of this taxon with separate subfamilial status, consistent with the phylogenetic results discussed below. Comparison with fossil accipitrids Australia has only two described pre-Pleistocene accipitrids. Pengana robertbolesi is from Sticky Beak Site in the Riversleigh World Heritage Area, of? Late Oligocene – Early Miocene age, which is now considered one of the Faunal Zone Asites (Travouillon et al. 2006) that onbiochronological grounds are slightly younger than the Pinpa LF (Woodhead et al. 2016). It is represented by a distal tibiotarsus (Boles 1993), and while of similar size, is easily distinguished from Archaehierax sylvestris by the following characters: the distal marginof thepons supratendineus isangled less steeply, ~ 30 ° relative to the long axis; the condyles have flattened sides in cranial aspect and are not medially and laterally expanded relative to the distal end of the shaft. Aquila bullockensis from themid-Miocene Camfield Beds (12 Ma) of Bullock Creek (Gaff and Boles 2010; Megirian et al. 2010) was described from a distal humerus – which was not preserved in Archaehierax sylvestris. However, A. bullockensis is very much (> 10 Ma) younger than Archaehierax sylvestris, much larger, and the morphology of the distal humerus was interpreted to be typical of species of Aquila. Archaehierax sylvestris has many features on other bone elements that exclude close affinity with both Aquila and the Aquilinae, so conspecificity with A. bullockensis can be ruled out. In relation to Oligocene-age fossil accipitrids from elsewhere in the world, the geographic isolation of Australia makes it unlikely that any described species are closely related to Archaehierax sylvestris. As reviewed in the Introduction, most late Oligocene and early Miocene accipitrid species are found in North America and Europe. Nearly all of them are described from a single skeletal element, making assessment of relationships with Archaehierax sylvestris difficult. The late Oligocene – early Miocene accipitrids from North America, including the relatively complete Palaeoplancus sternbergi, are all easily distinguished from Archaehierax sylvestris by size, and by morphology of the distal tarsometatarsus; specifically, trochlea metatarsi II is relatively broader and / or the intertrochlear incisions are much narrower. Four Oligocene fossil accipitrids are described from Europe, all but one of which is based on a single bone: Aquilavus hypogaea (Milne-Edwards, 1892), from the Quercy fissure fillings, is incomparable as it is based on a femur. Aquilavus corroyi (Gaillard, 1939), also from Quercy fissure fillings, was described from a tarsometatarsus that resembles Milvus according to Mayr (2009). It lacks the wide incisura intertrochleae of Archaehierax sylvestris, and the flange on the trochlea metatarsi II is oriented more medially (Gaillard 1939, Figure 1). Palaeohierax gervaisii (Milne-Edwards, 1863), late Oligocene France, is described from a tarsometatarsus and is larger than ‘ A. ’ corroyi. Compared to Archaehierax sylvestris, the incisura intertrochleae are narrow and the flange on trochlea metatarsi II is oriented more medially (Milne-Edwards 1863, Plate 183, Figures 1 - 10). Aviraptorlongicrus Mayr and Hurum, 2020, of early Oligocene age from Poland, is described from a complete skeleton. It is a very small accipitrid with highly elongate legs like those seen in species of Accipitrinae, which clearly distinguishes it from Archaehierax sylvestris. There are two Middle Oligocene species from Mongolia; Buteo circoides Kurochkin, 1968 (distal ulna), and Venerator (‘ Tutor ’) dementjevi (Kurochkin, 1968) (distal humerus). Only B. circoides can be directly compared to Archaehierax sylvestris, with images indicating the tuberculum carpale is less prominent of the ventral condyle, and the ventral condyle has greater distal extent than the dorsal condyle (Kurochkin 1968, Figure 1). Three fossil accipitrids are known from early Miocene deposits of Europe; Promilio incertus (Gaillard, 1939) was described from a right tarsometatarsus from Chavroches, France, which lacks the wide incisura of Archaehierax sylvestris, the flange on the trochlea metatarsi II is oriented more medially, and the hypotarsal crests are of roughly equal craniocaudal depth (Gaillard 1939, Figure 9). Aquilavus priscus (Milne-Edwards, 1863), described from a tarsometatarsus, tibiotarsus and carpometacarpus, is from Auvergne, France. It is larger than P. gervaisii. Compared to Archaehierax sylvestris, the incisura intertrochleae are narrow and the flange on trochlea metatarsi II is oriented more medially (Milne-Edwards 1863, Plate 184, Figures 1 - 4). On the carpometacarpus, the os metacarpale minus is flat, the processus alularis is less distinct from the distal processus extensorius, and the facies articularis digitalis major has less distal extent than the facies articularis digitalis minor (Milne-Edwards 1863, Plate 184, Figures 14 - 16). The tibiotarsus seems to lack a distinct scar or rugosity for the distal retinaculum extensorium (Milne-Edwards 1863, Plate 184, Figures 11 - 13). Aquilavus depredator (Milne-Edwards, 1871), described from a tarsometatarsus, is from Saint-Gérand le Puy, France. Compared to Archaehierax sylvestris, the incisura intertrochleae are narrow and the flange on trochlea metatarsi II is oriented more medially (Milne-Edwards 1871, Plate 183 Figures 11 - 14; Plate 184, Figures 5 - 10). The middle Miocene accipitrids from Asia are all aegypiine vultures (Hou et al. 2000; Zhang et al. 2010, 2012; Li et al. 2016) and so are not closely related (see phylogenetic analysis below).	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0017FF9EFC14FA67FE95F886.taxon	description	Subfamily indet. Gen. et sp. indet.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0017FF9EFC14FA67FE95F886.taxon	materials_examined	Material Distal right humeral fragment, preserving a relatively unworn distal end and 16.2 mm of shaft, and some associated fragments of the shaft, SAMA P. 58917.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0017FF9EFC14FA67FE95F886.taxon	description	Measurements (mm) Distal width 15.4, least shaft width 8.3, total depth 8.5, condylus dorsalis depth 8.3, condylus dorsalis width 5.2, condylus ventralis depth 5.1, condylus ventralis width 7.3, epicondylus ventralis depth 7.0.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0017FF9EFC14FA67FE95F886.taxon	materials_examined	Locality, stratigraphy and age 31 ° 07.568 ʹ S; 140 ° 12.737 ʹ E. Site 11, Lake Pinpa, Frome Downs Station, South Australia, Namba Formation, Pinpa LF, late Oligocene. Collected by A. Camens, T. Worthy and W. Handley, 24 – 26 September 2015.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0017FF9EFC14FA67FE95F886.taxon	discussion	Remarks The fossil can be excluded from other raptor families on the following features:	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0017FF9EFC14FA67FE95F886.taxon	description	Falconidae (falconid state in brackets): the condylus dorsalis is thickened and rounded distally (consistently narrow and rectangular); the processus flexorius ends proximal to the condylus ventralis (equidistant). Pandionidae (state for Pandion haliaetus in brackets): a shallow fossa m. brachialis (deep); a flat epicondylus dorsalis (prominently projecting); a flat epicondylus ventralis (prominent); the fossa olecraniis shallow (deep); thesulcus scapulotricipitalis is shallow (deep). Cathartidae (cathartid state in brackets): a shallow fossa m. brachialis (deep); a lack of pneumatisation in the fossa m. brachialis (present); a flat epicondylusventralis (prominent). Sagittariidae (sagittariid state in brackets): the two fossae marking the attachment points for the lig. collaterale dorsale are positioned roughly adjacent to each other (cranial-most fossa slightly proximal to and abutting caudal fossa in sagittariids). The fossil is broadly similar to accipitrids and displays the following features: (1) The tuberculum supracondylare dorsale (Figure 11 A: PSD) is located well-proximal to the condylus dorsalis (Figure 11 A: CD) and is small, barely projecting dorsally of the shaft, but projects slightly cranially as a proximodistally elongate rugosity; (2) the dorsal face / shaft margin between the tuberculum supracondylare dorsale and the epicondylus dorsalis is mildly inflated; Two shallow scars for the m. extensor carpi radialis are present on the tuberculum supracondylare dorsale (Figure 11 C: MECR), (3) the larger palmar attachment scar on the cranial face adjacent to the dorsal margin is oval (4) and the smaller dorsal scar is located on the dorsal face of the processus. (5) In caudal view, the processus flexorius (Figure 11: PF) terminates proximal to the condylus ventralis (Figure 11 A: CV) but is prominent ventrally. (6) The sulcus scapulotricipitalis (Figure 11 B: SST) forms a shallow but broad notch roughly 2 mm wide on the caudal face. (7) The fossa olecrani (Figure 11 B: FO) is moderately deep, defining well the dorsal margin to the processus flexorius but does not create a discontinuity with the sulcus humerotricipitalis. (8) The sulcus humerotricipitalis (Figure 11 B: SHT) is very shallow, and at 5.3 mm wide extends over half of shaft width of 9.7 mm at the same point. (9) The fossa m. brachialis (Figure 11 A: FB) is shallow but distinct, with a proximodistal length of 13.8 mm extending well proximal to the tuberculum supracondylare dorsale, and a maximum dorsoventral width of 7.3 mm level with the proximal margin of the tuberculum supracondylare dorsale. In contrast, the shaft width measures 10.1 mm at the same point. Within the fossa, the impressio m. brachialis is slightly deeper. (10) The fossa is well separated (3 mm) from the dorsal margin of the shaft. (11) The epicondylus ventralis (Figure 11 A: EV) is indistinct from the ventral margin and does not project ventrally past the processus flexorius. (12) Asingle distinct, shallow insertion scar is present on the ventrodistal section of the epicondylus ventralis, with a very faint and shallow second insertion ventrally adjacent to it. These insertions serve as the attachment point for the m. flexor carpi ulnaris. (13) The tuberculum supracondylare ventrale (Figure 11 A: TSV) projects cranially but not ventrally from the shaft. (14) Ashallow insertion scar for the pronator superficialis is present just proximal to the tuberculum on the dorsal face. (15) The condylus dorsalis (Figure 11 A: CD) is 5.9 mm proximodistally long, 4.7 mm dorsoventrally wide and 8.6 mm craniocaudally deep. (16) Two small, very shallow insertion scars are present on the caudal section of the dorsal face of the condylus dorsalis by the distal margin (Figure 11 C: CDCS), directly craniocaudally adjacent to each other. (17) The condylus ventralis is 4.5 mm proximodistally long, 7.3 mm dorsoventrally wide and 5 mm craniocaudally deep. (18) The condylus dorsalis is separated by a distinct notch from and set well proximal to the distal margin of the condylus ventralis in cranial view. (19) The incisura intercondylaris (Figure 11: II) is narrow, roughly 1.1 mm wide, but distinct. (20) The processus flexorius is surpassed distally by the condylus ventralis in caudal view, and strongly projects ventrally in caudal view. (21) The ventral margin of the condylus ventralis is not separated by a notch from the processus flexorius in cranial view. Extant accipitrids differ as follows: (Trait 1) The tuberculum supracondylare dorsale projects much further dorsally in all subfamilies and species except Pernis apivorus (Perninae), Polyboroides typus (Gypaetinae, non-projecting), Aquilinae, Accipitrinae and species of Buteo (Buteoninae). (16) The insertion scars towards the caudal margin of the condylus dorsalis are both deep in all subfamilies except Elaninae and Accipitrinae, with the latter having the cranial-most insertion being shallow and the caudal-most deep.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0017FF9EFC14FA67FE95F886.taxon	discussion	The fossil has the most similarities to species from the subfamily Elaninae (see SI. 2 for more detailed differential comparisons), but differs markedly in regards to the inflation of the dorsal face between the tuberculum supracondylare dorsale and the epicondylus dorsalis, the size and shape of the palmar and dorsal attachment scars for the m. extensor carpi radialis, the distinct depression in the section of dorsal face caudal to the tuberculum supracondylaris and the epicondylus dorsalis, the sulcus humerotricipitalis width, the fossa m. brachialis length, the configuration of the insertion scars on the distal epicondylus ventralis, the position of the distal margin of the condylus dorsalis relative to that of the condylus ventralis in cranial view, the ventral projection of the processus flexorius, and the connectivity of the condylus ventralis and entepicondyle in cranial view. As the Archaehierax sylvestris specimen SAMA P. 54998 lacks a preserved distal humerus, it cannot be compared to SAMA P. 58917. However, it is not believed to belong to the same species due to the significantly smaller size of SAMA P. 58917 from the humerus size predicted for SAMA P. 54998 (see comparative measurements below).	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0019FF9AFC14FF78FBEEFAAB.taxon	description	Subfamily indet. Gen. et sp. indet.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0019FF9AFC14FF78FBEEFAAB.taxon	materials_examined	Material NMV P. 222435, distal left femur preserving intact distal end and 15.5 mm of shaft.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0019FF9AFC14FF78FBEEFAAB.taxon	description	Measurements (mm) Preserved length 26, DW 13.3, least SW 7.3, preserved condylus medialis depth 9.7, condylus medialis width 5.6, condylus lateralis depth 11.0, condylus lateralis width 6.1.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0019FF9AFC14FF78FBEEFAAB.taxon	materials_examined	Locality, stratigraphy and age 31 ° 11.237 ’ S 140 ° 13.944 ʹ E Ericmas Quarry, Lake Namba, Frome Downs Station, South Australia, Namba Formation, Ericmas LF, late Oligocene. Collected by T. Flannery, 7 / 4 / 83.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0019FF9AFC14FF78FBEEFAAB.taxon	discussion	Remarks The specimen can be excluded from the Pandionidae and Cathartidae by the presence of a single muscular attachment on the planum popliteum, and from Falconidae and Sagittariidae by the linea intermuscularis caudalis remaining level and visible on the medial margin of the caudal face.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0019FF9AFC14FF78FBEEFAAB.taxon	description	The femur is consistent with accipitrids and has the following morphology. (Trait 1) The linea intermuscularis caudalis (Figure 12 C: LIC) is highly distinct, running along the medial border of the caudal shaft face in a raised line, (2) but is not continuous with the tuberculum m. gastrocnemialis medialis, so there is no crista supracondylaris medialis. (3) The secondary origin point for the ligamentum collateralis lateralis is very faint and shallow, barely distinct from the surface of the bone. (4) The fovea tendineus m. tibialis cranialis is shallow. (5) The fossa poplitea (Figure 12 B: FPop) is shallow, deepening slightly towards the distal end immediately proximal to the condyles. (6) The attachment scar on the planum popliteum (Figure 12 B: PPAP) is positioned medially. (7) The impressio m. gastrocnemialis lateralis (Figure 12 D: IG) is large and shallow. (8) The epicondylus lateralis (Figure 12 A: EL) is short and very robust but has little projection from the condylus lateralis. The distal femur NMV P. 222435 is from an accipitrid which exhibits the most similarity to those of species in Buteoninae, Aegypiinae, and most of Elaninae (see SI. 2 for more detailed differential comparisons). It mainly differs from species in these subfamilies in lacking a prominent crista supracondylaris medialis, the position and shape of the attachment point on the planum popliteum, and the weak projection of the epicondylaris lateralis. As the distal femur is not a highly diagnostic section of the accipitrid skeleton, and the distal femur is not preserved in Archaehierax sylvestris specimen SAMA P. 54998, NMV P. 222435 is regarded as gen. et. sp. indet. The size difference between NMV P. 222435 and the predicted size of the distal femur of SAMA P. 54998 is greater than would be predicted from typical sexual dimorphism, which makes it unlikely the two are representatives of the same species (see comparative measurements below). Size comparisons of the three fossils The width measurements of the proximal humerus, distal humerus, distal tibiotarsus and distal femur of extant taxa were compared (see Appendix 1, Table S 2) and showed that the distal width of the humerus was between 80 % and 90 % of the proximal width of the humerus, while the distal width of the tibiotarsus was between 75 % and 110 % the distal width of the femur in extant accipitrids. If the bones of Archaehierax sylvestris had similar ratios, then it can be predicted that the width of the missing distal humerus should fall in the range 23.4 – 26.4 mm, while that of the missing distal femur should be between 15.8 and 22.0 mm broad. Based on this, both the isolated distal femur NMV P 222435 and the isolated distal humerus SAMA P. 58917 are too small to belong to an individual the size of the A. sylvestris holotype. However, sexual dimorphism is known to be considerable and common in accipitrids (Brown and Amadon 1968; Marchant and Higgins 1993) and raises the possibility that these isolated fossils may belong to a smaller sex of the onespecies if they fall within a certain size range. Field et al. (2013) devised multiple algorithms for predicting body mass from skeletal measurements, while Campbell and Marcus (1992) predicted body mass based on the femur and tibiotarsus circumference. Using these, the mass of the bird for the Archaehierax sylvestris holotype is estimated as 3.7 kg based on the length of the coracoid facies articularis humeralis, 4.6 kg by the least shaft diameter / width of the tarsometatarsus, and 3.2 kg based on tibiotarsus least shaft circumference. The mass of the bird represented by the distal femur is calculated at 2 kg based on femur shaft width / diameter, or 1.6 kg based on shaft circumference. The mass of the bird represented by the distal humerus is calculated at 1.5 kg based on shaft width / diameter, or 1.6 kg based on circumference. Assuming these predictions are accurate, the femur represents a bird 46 – 67 % smaller than the skeleton specimen, and the humerus one 60 – 67 % smaller. This would be pushing accipitrid sexual dimorphism to its extreme limits, making it unlikely that the fossils represent a single species. However, these mass predictions use different elements, limiting their comparability. Nevertheless, while considering it likely that at least two accipitrids are represented, we consider it unwise to describe the smaller as a second species when size would be the only distinguishing factor and their congeneric status cannot be assessed.	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
D14B87DD0019FF9AFC14FF78FBEEFAAB.taxon	discussion	PCA analysis of limb measurements	en	Mather, Ellen K., Lee, Michael S. Y., Camens, Aaron B., Worthy, Trevor H. (2021): An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba formation, South Australia. Historical Biology 34 (7): 1175-1207, DOI: 10.1080/08912963.2021.1966777, URL: http://dx.doi.org/10.1080/08912963.2021.1966777
