taxonID	type	description	language	source
03B6879EFFB1D90FFC04AB40DA1EFBDE.taxon	description	Z o o b a n k L S I D. — u r n: l s i d: z o o b a n k. org: act: AD 147252 - 369 F- 40 D 1 - A 7 F 9 - 4233262 A 804 C	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D90FFC04AB40DA1EFBDE.taxon	materials_examined	Type species: Ferrequitherium sweeti sp. nov. Other species: Type species only. Etymology: Ferrum, Latin noun, iron; equus, Latin noun, horse; therion, Latin noun, beast. In reference to the Canadian Pacific Railway tracks below the Trainspotting locality. Occurrence: Earliest Tiffanian (Ti 1, Late Palaeocene) of south-western Alberta, Canada.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D90FFC04AB40DA1EFBDE.taxon	etymology	Etymology: Ferrum, Latin noun, iron; equus, Latin noun, horse; therion, Latin noun, beast. In reference to the Canadian Pacific Railway tracks below the Trainspotting locality.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D90FFC04AB40DA1EFBDE.taxon	distribution	Occurrence: Earliest Tiffanian (Ti 1, Late Palaeocene) of south-western Alberta, Canada.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D90FFC04AB40DA1EFBDE.taxon	diagnosis	Diagnosis: As for the type species by monotypy.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D90FFE90AF00DAEEFDA5.taxon	materials_examined	Type genus: Horolodectes Scott, Fox & Webb, 2006. Other genera: Ferrequitherium gen. nov.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D90FFE90AF00DAEEFDA5.taxon	etymology	Etymology: In reference to Horolodectes. Occurrence: Earliest Tiffanian (Ti 1) to Middle Tiffanian (Ti 3) (Late Palaeocene) of Alberta, Canada.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D90FFE90AF00DAEEFDA5.taxon	diagnosis	Diagnosis: Differs from other Eutheria in having unique combination of lower molars with talonids longer and wider than trigonids, protoconid arm of protocristid shorter than metaconid arm, and m 3 with enlarged and closely approximated entoconid, entoconulid and hypoconulid positioned along the lingual margin of crown. Differs further in lower molars combining low trigonid that becomes increasingly anteroposteriorly compressed from m 1 to m 3, tall and trenchant paraconid lingual in position and closely positioned to metaconid, cristid obliqua contacting postvallid wall labial to protocristid notch and m 1 – 2 hypoconulid anteroposteriorly compressed, with nearly flat basin-facing surface.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D907FC2FAD4FDD0CF886.taxon	description	(FIGS 2 – 7; TABLES 1 – 2; SUPPORTING INFORMATION, APPENDIX S 2) Z o o b a n k L S I D. — u r n: l s i d: z o o b a n k. org: act: 9 CEF 0352 - D 12 F- 46 DD-A 325 - 1231 C 3 EFA 4 C 7	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D907FC2FAD4FDD0CF886.taxon	materials_examined	Holotype: TMP 2013.048. 0075, incomplete left dentary with p 3 – 4, m 1 – 3 (Fig. 3 A – D).	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D907FC2FAD4FDD0CF886.taxon	description	Hypodigm: See Supporting Information, Appendix S 2.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D907FC2FAD4FDD0CF886.taxon	etymology	Etymology: Named in honour of the late Dr Arthur R. Sweet (Geological Survey of Canada) for his many contributions to Late Cretaceous and Palaeogene palynology. Occurrence: Earliest Tiffanian (Ti 1, Late Palaeocene) of south-western Alberta, Canada.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D907FC2FAD4FDD0CF886.taxon	diagnosis	Diagnosis: Differs from Horolodectes in having lower premolars with more nearly vertical and less trenchant protoconid and better-developed lower premolar talonid, in p 4 having metaconid and basined talonid with more distinct entoconid and hypoconid. Differs further from Horolodectes in P 4 having T-shaped occlusal outline, with weaker ectocingulum and postparacrista, and in P 4 and lacking neomorphic crest extending labially from paracone apex. Differs further from Horolodectes in upper molars having less swollen conules, weaker notches in the protocristae at their junction with the conules, weaker notch in the ectocingulum labial to the deepest part of the centrocrista, and lacking neomorphic crest extending labially from paracone apex.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFB1D907FC2FAD4FDD0CF886.taxon	description	Description Specimens of F. sweeti include isolated teeth and incomplete jaws with teeth. Associating the upper and lower teeth was justified primarily on the close resemblance to homologous teeth in H. sunae (see below), a strong occlusal fit between opposing upper and lower molars, and frequency of occurrence (for example, F. sweeti is the best represented eutherian in the Trainspotting mammalian fauna). Maxilla and upper dentition The maxilla is poorly preserved on TMP 2017.025.0317, and preserves little in the way of informative features. Although parts of the facial process remain, there is no evidence for the position of the infraorbital foramen, or for the position of the maxillary process of the zygomatic arch. The upper incisors, canine, and pre-ultimate premolars of F. sweeti are unknown. P 4 (Fig. 2): The P 4 of F. sweeti is known from 11 specimens, one of which (TMP 2017.025.0317) is an incomplete maxilla containing P 4 and the first two molars (Fig. 2 F – H). The crown is T-shaped in occlusal outline, and is dominated by an inflated paracone and smaller protocone. The paracone is subcircular in cross-section and leans somewhat posteriorly, with long, gently sloping anterior and shorter, more nearly vertical posterior surfaces. The stylar shelf is undeveloped, and the ectocingulum is complete labially. A faint preparacrista extends along the anterior surface of the paracone to the parastylar corner, where it unites with the ectocingulum and precingulum. The parastylar region is drawn out in a distinct lobe, and supports a low but prominent parastyle. The postparacrista runs posteriorly from the apex of the paracone, uniting with a short, low premetacrista and forming a sharp notch. The metacone is small but distinct, and is developed on the posterior shoulder of the paracone approximately halfway between the apex of the paracone and the metastylar corner of the crown. The postmetacrista bends sharply labially as it nears the posterior margin of the crown where it unites with the ectocingulum, but not the postcingulum, which terminates just lingual to the metastylar corner. A weak swelling in the region of the metastyle occurs on several specimens (e. g. TMP 2015.069.0169). The protocone is both smaller and lower than the paracone, oriented more nearly vertically, and is positioned slightly anterior to the midwidth of the crown. The preprotocrista extends anterolabially towards the base of the paracone, uniting with the prominent precingulum; the stout postprotocrista curves posteriorly and slightly labially from the protocone apex, but fades away before reaching the postcingulum. A third crest, weaker than either of the protocone cristae, extends directly labially from the protocone apex towards the base of the paracone. Neither paraconule nor metaconule is developed. M 1 (Figs 2 F – H, 3 A – E): The crown of M 1 is subtriangular in occlusal outline, with the labial margin slightly longer than the lingual margin. The low, robust ectocingulum extends along the labial margin of the crown, and the stylar shelf is narrow. A shallow ectoflexus divides the labial margin of the crown into weak para- and metastylar lobes, with the metastylar lobe projecting further labially. The preparacrista is stout and extends anteriorly from the apex of the paracone, joining the preparaconule crista + paracingulum at the parastylar corner. The centrocrista is straight, with no deflection of either the postparacrista or premetacrista towards the ectocingulum. The low postmetacrista curves sharply labially from the apex of the metacone to the metastylar corner of the crown, where it joins the ectocingulum. The paracone is slightly taller than the metacone, and the two cusps are subequal in size; both cusps are weakly convex labially and strongly swollen lingually. The paraconule and metaconule are well developed, somewhat swollen, and positioned near the base of the paracone and metacone, respectively. The short preparaconule crista extends anteriorly and slightly labially before continuing as the paracingulum towards the parastylar corner of the crown. The postmetaconule crista curves posterolabially and continues as the metacingulum before ending abruptly near the base of the metacone, rather than joining the postmetacrista. The postparaconule crista meets a short, lingually directed crest arising from low on the lingual side of the paracone; a weak notch is formed at their union. The premetaconule crista originates very low on the metaconule, and extends labially a short distance before fading away. A massive protocone dominates the lingual side of the crown, its apex leaning slightly anteriorly; the cusp is positioned slightly anterior to the midwidth of the crown. The protocone cristae are well developed, and form slit-like notches at their junction with the paraconule and metaconule. The precingulum and postcingulum are both robust, and although both cingula extend labially, neither joins the conule cristae and instead fade out near the base of the paraconule and metaconule, respectively. The postcingulum is somewhat swollen in the area of where a hypocone might be expected, but no distinct cusp is developed. M 2 (Figs 2 F – H, 3 F – J): The M 1 and M 2 of F. sweeti are closely similar in size and morphology. The crown of M 2 is wider than that of M 1, and the occlusal outline is more similar to that of an isosceles, rather than equilateral triangle. The crown of M 2 differs most notably from that of M 1 in having a more prominent and labially extending parastylar lobe, and a slightly deeper ectoflexus that divides the labial margin into more distinct para- and metastylar lobes. The M 2 differs further from M 1 in having a proportionally larger paracone relative to metacone, a slightly shorter postmetacrista, and a lingual slope of the protocone that is both longer and shallower than that on M 1. M 3 (Fig. 3 K – T): The M 3 of F. sweeti is smaller than either M 1 or M 2, subtriangular in occlusal outline, and lacks any development of a metastylar lobe. As with M 1 and M 2, the stylar shelf on M 3 is undeveloped, and the ectoflexus is very shallow, faintly dividing the labial margin into anterolabially projecting parastylar and smoothly rounded metastylar areas. The ectocingulum is robust anteriorly, but diminishes posteriorly, fading away as it approaches the metacone. The preparacrista is stout and extends anteriorly and labially, uniting with the paracingulum and ectocingulum. The paracone is large, subconical, and leans slightly anteriorly. The metacone is about half the size and height of the paracone, and is joined to the latter by a broadly notched centrocrista. Both conules are strongly developed and appressed to the bases of the paracone and metacone, and although the paraconule cristae are both well developed, only the postmetaconule crista is present at the metaconule. The protocone is about the same height as the paracone, but is much more massive, constituting nearly one-third the width of the crown. As on M 1 and M 2, the protocone cristae on M 3 form slit-like notches at their union with the conules. The protocone cingula are robust but incomplete lingually. A hypocone is not developed. Dentary and lower dentition The lower dentition of F. sweeti is known from incomplete jaws and isolated teeth that together document p 2 – 4, m 1 – 3. Nothing is known of the lower incisors or canine, and little can be said of the dentary other than the size and positions of the two mental foramina. The more anterior foramen opens ventral to the anterior root of p 2, and its large, subcircular aperture faces anteriorly and laterally (Fig. 4 E). The more posterior foramen opens ventral to the posterior root of p 3 and faces laterally (Fig. 4 A). p 1: The p 1 remains undiscovered in F. sweeti, although its presence is confirmed by its alveolus in TMP 2015.069.0039 (Fig. 4 E – G). The alveolus for p 1 is subovate, being somewhat bilaterally compressed, and is oriented posteromedially-anterolaterally, suggesting the tooth may have projected anteriorly and laterally. A short diastema separates the p 1 alveolus from p 2. p 2: p 2 is known from a tentatively referred specimen, TMP 2015.069.1134 (Fig. 6 A – D), as well as from its two alveoli in TMP 2015.069.0039. The crown of p 2 is dominated by a tall and slightly recurved protoconid anteriorly, and a low transversely oriented crest posteriorly. The protoconid is mildly inflated towards its base labially, but is only weakly convex lingually; the postvallid surface is virtually flat. A weak paracristid originating at the protoconid apex extends anterolingually towards the base of the crown, but neither paraconid nor metaconid is developed. The talonid consists of a low, transversely oriented crest: the crest is approximately half the width of the protoconid, slightly higher labially than lingually, and curves anteriorly at the lingual margin of the crown, enclosing a shallow basin. Weak exodaenodonty is developed at the posterior root. A diastema, nearly twice the length of the more anterior diastema, separates p 2 and p 3. p 3: The p 3 of Ferrequitherium is known from three specimens. The crown is larger and taller than that of p 2, and the protoconid is more inflated (Figs 4, 6 D – F). As with p 2, the crown of p 3 consists of a large, recurved protoconid and a low transverse crest. A weak paracristid arises from the protoconid apex and curves anterolingually, becoming more pronounced as it descends the protoconid; a tiny paraconid can be developed at the terminus of the paracristid. A metaconid is not developed. One or two poorly defined crests extend posteroventrally from the apex of the protoconid, but fade away before reaching the talonid. The talonid is low, approximately one-third the height of the protoconid, and consists primarily of a transverse crest; as with p 2, the talonid crest on p 3 is higher labially, and extends to the lingual margin of the crown where it turns abruptly anteriorly, enclosing a shallow basin. The crest becomes slightly thicker at the posterolingual margin of the crown, in the position of an entoconid, but distinct talonid cusps are otherwise not developed. Weak exodaenodonty can be developed at the posterior root. dp 4 (Fig. 6 G – I): Three dp 4 s are provisionally referred to Ferrequitherium. The crown of dp 4 is molariform, with a tricuspid trigonid and wide, deeply basined talonid. The protoconid is the largest and tallest trigonid cusp, followed by a slightly smaller and lower metaconid, and a still lower but prominent paraconid. The protoconid and metaconid are inflated, subconical, and are connected by a deeply notched protocristid. A sharp paracristid extends anteriorly from the protoconid, forming a deep notch at its union with the paraconid. The paraconid is anteroposteriorly compressed and offset anteriorly from the protoconid and metaconid, with its apex aligned with the deepest part of the protocristid notch. A short but prominent crest extends lingually from the paraconid apex, but fades away, leaving the trigonid open lingually. The talonid is significantly wider than the trigonid, and consists of a massive hypoconid and smaller, subequal entoconid and hypoconulid. The cristid obliqua contacts the postvallid wall low and labial to the protocristid notch, and the hypoconid is connected to the hypoconulid by a well-developed hypocristid; both cristid obliqua and hypocristid are heavily worn. The hypoconulid is slightly closer to the entoconid than to the hypoconid, but a shallow notch separates the two cusps, and the postcristid is undeveloped. A weak precingulid occurs below the paracristid notch, but the postcingulid is undeveloped. p 4 (Figs 4, 6 J – L): The p 4 of Ferrequitherium is known from ten specimens. The crown is slightly taller than that of p 3, but is similarly subrectangular in occlusal outline, with a weak constriction developed at the hypoflexid. The trigonid consists primarily of a massive, inflated and recurved protoconid, and a smaller metaconid. A stout paracristid extends anteriorly from the protoconid apex, becoming more prominent and blade-like as it descends along the anterior surface of the protoconid. As the crest nears the base of the protoconid, it can curve gently lingually before fading away, or it can turn sharply lingually, forming a low platform; in either case, a paraconid is not developed. A weak precingulid is sometimes developed, but does not extend far onto the labial side of the protoconid. The metaconid is considerably smaller and shorter than the protoconid, varying from about one-third to one-half the size of the latter, and occurs directly lingual or slightly posterolingual to the apex of the protoconid. The metaconid and protoconid are connected by a weak but sharply notched protocristid. The talonid is about half the height of the trigonid, and consists primarily of a small hypoconid and larger, taller, but more poorly differentiated entoconid. The hypoconid occurs at the posterolabial corner of the talonid and is connected to the postvallid wall by an anterolingually directed cristid obliqua; the cristid obliqua can meet a short crest low on the postvallid wall near the midline. The entoconid is nearly twice the size of the hypoconid, with inflated lingual and posterior walls, but with a more poorly differentiated apex; it is connected to the hypoconid by a high, transverse crest. On one specimen, TMP 2014.047.0172, a small, weakly differentiated hypoconulid is present. A low entocristid connects the entoconid to the postvallid wall. Together, the talonid cusps and crests enclose a shallow basin that is skewed slightly labially. Exodaenodonty is developed at both roots, but is especially prominent posteriorly. m 1 (Figs 4, 5, 6 M – O): The crown of m 1 is weakly hourglass-shaped in occlusal outline, with the talonid bulging labially and lingually past the level of the trigonid. The trigonid consists of an equidistant protoconid, paraconid and metaconid, with the three cusps forming a near-equilateral triangle in outline. The principal cusps are subconical and sharply pointed, have inflated interior walls and appear swollen towards their bases. The metaconid is slightly taller than the protoconid, although the cusps are subequal in size, and with the metaconid occurring slightly posterior to the level of the protoconid; the two cusps are connected by a deeply notched protocristid, of which the protoconid arm is shorter than the metaconid arm. The paraconid is about half the size and height of the protoconid and is positioned slightly labial of the lingual margin of the crown. The paracristid extends anteriorly from the protoconid apex, and then turns sharply lingually, continuing to the paraconid. The talonid is approximately two-thirds to three-quarters the height of the trigonid, and the slightly concave valley-facing sides of the hypoconid and entoconid form a deep, weakly V-shaped floor that becomes increasingly concave with wear. The hypoconid is the largest talonid cusp, occupying nearly half the width of the talonid; the cusp is connected to the postvallid wall by a cristid obliqua that contacts the trigonid low and labial to the level of the protocristid notch. The entoconid is slightly taller but smaller than the hypoconid, and connects to the trigonid by a prominent, moderately notched entocristid. Faint swellings in the position of a mesoconid and entoconulid can be present on the cristid obliqua and entocristid, respectively, but distinct cuspids are not developed. The hypoconulid is lower than the entoconid, is anteroposteriorly compressed with a flat basinfacing wall and is positioned close to the entoconid; on one specimen, TMP 2014.047.0179, a small cuspid is developed off of the labial side of the hypoconulid. The postcristid is short, steep and incised by a narrow notch, separating the entoconid and hypoconulid; the hypocristid curves posterolingually from the hypoconid, joining that cusp with the hypoconulid. A short but prominent precingulid is present, but does not continue labially as an ectocingulid; the postcingulid is weak or undeveloped. m 2 (Figs 4, 5, 6 P – R): The crown of m 2 resembles that of m 1, but is larger overall, with a more anteroposteriorly compressed trigonid and considerably wider talonid. The trigonid cusps are less robust than their counterparts on m 1, but are nonetheless inflated, particularly the internal walls, and the postvallid wall is oriented transversely, rather than oblique to the anteroposterior axis of the crown. The metaconid is the largest trigonid cusp, and is connected to the shorter protoconid by a deeply notched protocristid; as on m 1, the protocristid is asymmetric, with the metaconid arm being longer than the protoconid arm. A stout paracristid extends a short distance anteriorly from the apex of the protoconid, and then bends sharply lingually, continuing to the subconical paraconid, which is both taller and closer to the metaconid than on m 1. The paracristid is both longer and more transverse than on m 1, and the paraconid is more nearly vertical in its orientation and more fully incorporated into the paracristid. The talonid resembles that on m 1, but is longer and wider, and the entoconid is taller. The hypoconid is the largest talonid cusp, followed by a smaller but equally tall entoconid and still smaller and lower hypoconulid; the hypoconulid is somewhat appressed to the entoconid, but is separated from the latter by a slit-like notch in the postcristid. On some specimens (e. g. TMP 2015.069.0943, not figured) a small cusp is developed off of the labial shoulder of the hypoconulid, effectively ‘ doubling’ the hypoconulid. The cristid obliqua contacts the postvallid wall labial to the level of the protocristid notch, and the sharply notched entocristid continues dorsally along the postvallid wall as a metastylid crest. As on m 1, a poorly defined mesoconid and entoconulid can be present on the cristid obliqua and entocristid, respectively. The precingulid is more prominent and labially extending than on m 1, but an ectocingulid remains undeveloped. m 3 (Figs 4, 5, 6 S – X): The m 3 of F. sweeti is longer than either m 1 or m 2, but is narrower and slightly lower crowned. The trigonid is anteroposteriorly compressed, even more so than on m 2, and the paraconid is positioned closer to the metaconid. The trigonid cusps are less robust than those on m 2, but their internal walls are likewise inflated, the metaconid larger and taller than the protoconid, and the protocristid is similarly notched and asymmetric in its proportions. The paracristid extends a short distance anteriorly from the protoconid apex before turning sharply lingually; the paraconid arm of the paracristid is longer and more transversely oriented than on m 1 or m 2, and the paraconid is more fully incorporated into the paracristid. The talonid is longer and slightly narrower than on m 2, but is nonetheless wider than the trigonid, and the principal cusps are well developed and together enclose a weakly V-shaped floor that becomes more evenly concave with wear. The talonid is dominated by a massive hypoconid that occupies greater than half of its width; a robust cristid obliqua connects the hypoconid to the postvallid wall, and a weak swelling marks the position of an incipient mesoconid. The entoconid, slightly smaller than the hypoconid, is positioned posterolingually and close to the hypoconulid; both cusps are swollen and are separated by a notched postcristid. A prominent entoconulid is developed on the entocristid immediately anterior and lingual to the entoconid; the cuspid can be slightly smaller than either the entoconid or hypoconulid, or as large, but has similarly swollen walls, and is separated from the former by a shallow notch. The entoconulid, together with the entoconid and hypoconulid, defines the posterolingual margin of the talonid basin. The precingulid is conspicuous, and can continue along the labial surface of the protoconid as an ectocingulid to the hypoflexid. The postcingulid is weak or undeveloped.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
03B6879EFFBFD91CFF40AFA9DDF3FDA5.taxon	description	To examine the evolutionary relationships of Ferrequitherium and Horolodectes, a phylogenetic analysis was performed using a newly constructed character – taxon matrix. The matrix consists of 81 characters, compiled through a combination of direct observation of specimens and descriptions from the literature. The specimens and literature used in the analyses, character list and data matrix are presented in Supporting Information, Appendices S 2 – S 4. In addition to Ferrequitherium and Horolodectes, the analysis includes several of the taxa discussed in Scott et al. (2006) as potential near-relatives of Horolodectes, as well as additional taxa with dental morphologies that resemble that of Ferrequitherium. Taxon sampling The ingroup includes the following taxa: Horolodectes and Ferrequitherium: Ferrequitherium and its hypothesized close relative Horolodectes, are each monotypic and are represented by F. sweeti and H. sunae Scott, Fox & Webb 2006, respectively. Pentacodontidae: The Pentacodontidae Simpson, 1937 are a family of unusual, Palaeocene – Eocene-age eutherians characterized by moderately to greatly enlarged upper and lower fourth premolars and relatively unspecialized molars (Simpson, 1937; Gingerich et al., 1983; Gunnell et al., 2008). Simpson (1937) originally restricted Pentacodontinae (then considered a subfamily) to Aphronorus Simpson, 1935 and Pentacodon Scott, 1892, but the family has since been expanded to include several other North American and, potentially, European taxa (McKenna & Bell, 1997; De Bast & Smith, 2017). The broader relationships of Pentacodontidae remain unclear, although the opinions of Matthew (1909, 1918), Simpson (1937) and McKenna (1975) that link the group with pantolestids, as either a subfamily of Pantolestidae or a family within a more inclusive Pantolesta, have been accepted in recent studies (e. g. McKenna & Bell, 1997; Boyer & Georgi, 2007; Rankin, 2014). Scott et al. (2006) noted several similarities in the dentitions of Horolodectes and Aphronorus, and the genus is therefore included in this study. Aphronorus was scored using A. fraudator Simpson, 1935, the type species, and A. orieli Gazin, 1969. A second putative pentacodontid, Bisonalveus Gazin, 1956, was also included in this analysis. In the parts that can be compared, the dentition of this genus is similar to that of Ferrequitherium, particularly the upper molars and lower fourth premolar. Bisonalveus has long been considered a pentacodontid (e. g. Van Valen, 1967; Krause & Gingerich, 1983; Youzwyshyn, 1988; Fox & Scott, 2005), although its evolutionary relationships have not been examined in detail, and at least one recent, largescale analysis has hypothesized a bizarre sister-group relationship between the genus and a clade, including pantodonts and tillodonts (Halliday et al., 2017; and see Zack, 2009 for discussion). Bisonalveus was scored using Bisonalveus browni Gazin, 1956, the type species, and an as-yet unnamed new species from the late Palaeocene of Alberta (Scott, 2008). Bessoecetor Simpson, 1936: Bessoecetor is the oldest discovered pantolestid, known principally from Palaeocene deposits in the northern part of the Western Interior of North America (Russell, 1929; Simpson, 1936; Krause & Gingerich, 1983; Cifelli et al., 1995; Scott et al., 2002; Scott, 2008; Rankin, 2014). The genus was included in this analysis to test for potential broader pantolestan (i. e. exclusive of Pentacodontidae) affinities of Ferrequitherium and Horolodectes. Bessoecetor was scored using Bessoecetor septentrionalis (Russell, 1929): the species is one of the oldest and arguably most basal of the genus, and is particularly well documented, being known from dozens of specimens from Alberta and Montana (see, e. g. Simpson, 1936; Krause & Gingerich, 1983; Scott et al., 2002; Scott, 2008). Cimolestes Marsh, 1889: The genus Cimolestes was recently split into several genera, in recognition of the morphological disparity among its included species (Fox, 2015). Fox (2015) limited Cimolestes to the type species, C. incisus Marsh, 1889, and C. stirtoni Clemens, 1973, both from Late Cretaceous deposits of the Western Interior of North America, with the former being included in this analysis. Cimolestes is considered a basal cimolestan (McKenna & Bell, 1997) and was included in the analysis to test for broader cimolestan (i. e. exclusive of Pantolesta) affinities. Apheliscidae Matthew, 1918: The Apheliscidae are a family of small-bodied eutherians that have been traditionally allied with ‘ Condylarthra’, a widely recognized wastebasket taxon consisting of primarily Palaeocene to Eocene age, bunodont mammals (McKenna, 1960; Van Valen, 1967; Archibald, 1998; Zack et al., 2005 b). ‘ Condylarthra’ are thought to represent the initial radiation of ungulates, although compelling evidence linking any of the included lower-level ‘ condylarth’ taxa with crown group ungulates remains elusive. A subset of Apheliscidae, the Apheliscinae Zack, Penkrot, Krause & Maas, 2005 b, is characterized by enlarged upper and lower fourth premolars, a weak p 4 paraconid and metaconid, poorly developed molar cingulids, and inflated cusps (Zack et al., 2005 b; Penkrot et al., 2008). Apheliscines broadly resemble Ferrequitherium in these regards, and these are best seen in the dentition of Phenacodaptes Jepsen, 1930, from the Late Palaeocene of Wyoming, the upper molars and lower fourth premolar of which resemble those of Ferrequitherium. Phenacodaptes sabulosus Jepsen, 1930, the only known species of the genus, was scored in this analysis. In addition to Phenacodaptes, the Late Palaeocene Gingerichia Zack, Penkrot, Krause & Maas, 2005 b was also included; Gingerichia is recognized as the basalmost apheliscine (Zack et al., 2005 b). The genus is known from two species (G. geoteretes Zack, Penkrot, Krause & Maas, 2005 b and G. hystrix Zack, Penkrot, Krause & Maas, 2005 b), and scoring included both of these species. To test for broader apheliscid (i. e. exclusive of Apheliscinae) affinities, the North American Palaeocene genus Litomylus Simpson, 1935 was also included. Scoring decisions were based on Litomylus dissentaneus Simpson, 1935: Litomylus dissentaneus is reasonably well known and is represented by several well-preserved specimens documenting significant parts of the dentition. Arctocyonidae: Webb (1996) and Scott et al. (2006) noted similarities in the dentition of Horolodectes and those of ‘ Oxyclaenidae’ (sensu Matthew, 1915 and McKenna & Bell, 1997), a family of basal ‘ condylarths’ with generally plesiomorphic dentitions (Archibald 1998). There is little consensus on either the monophyly of the various ‘ oxyclaenids’ or how best to classify them (e. g. Cifelli, 1983; McKenna & Bell, 1997; Archibald, 1998; Muizon & Cifelli, 2000; Williamson & Carr, 2007; De Bast & Smith, 2013). Given these continuing uncertainties, the nomen Arctocyonidae is used here to refer to the possibly paraphyletic or even polyphyletic assemblage of basal ‘ condylarths’ exclusive of Oxyclaenus (which may be more closely related to mesonychids; Williamson & Carr, 2007), while recognizing that some of the constituent arctocyonid taxa may be monophyletic (e. g. Arctocyoninae sensu Archibald, 1998). Two arctocyonids were included in this analysis: Protungulatum Sloan & Van Valen, 1965, and Loxolophus Cope, 1885. Protungulatum is widely regarded as the most basal ‘ condylarth’, although its systematic position as a placental (i. e. within the eutherian crown group) or as a stem eutherian continues to be debated (e. g. Wible et al., 2007, 2009; Spaulding et al., 2009; Archibald et al., 2011; O’Leary et al., 2013; Halliday et al., 2016, 2017). The genus is first known from Late Cretaceous deposits of North America (Johnston, 1980; Fox, 1989; Archibald et al., 2011; Redman et al., 2015) but is best known from the Palaeocene of Montana (Sloan & Van Valen, 1965; Archibald, 1982; Lofgren, 1995). Dental characters for Protungulatum were scored using the type species, P. donnae Sloan & Van Valen, 1965, and an as-yet unnamed new species from the Puercan of Alberta. Loxolophus, a potentially non-monophyletic ‘ condylarth’ (see Hunter et al., 1997) known from Puercan and Torrejonian deposits in several areas of the North American Western Interior, was included as a derived arctocyonid; dental characters were scored for Loxolophus hyattianus Cope, 1885. Zhelestidae: The Zhelestidae are a family of Late Cretaceous, primarily Central Asian eutherians that have previously been linked to crown group ungulates (e. g. Archibald, 1998; Nessov et al., 1998; Archibald et al., 2001), but more recently have been considered stem eutherians (e. g. Ekdale et al., 2004; Wible et al., 2007; Chester et al., 2010; Archibald & Averianov, 2012). Scott et al. (2006) noted several similarities between zhelestids and Horolodectes, including teeth with low crowns and swollen cusps, molars with narrow stylar shelves, large conules, and lower molars with wide talonids and a closely approximated entoconid and hypoconulid. The dentition of Ferrequitherium resembles that of zhelestids in these features as well, but with additional similarities in the premolars, particularly the development of a metaconid on p 4 (= p 5 of zhelestids). Zhelestid characters were primarily scored for Aspanlestes atap Nessov, 1985; Aspanlestes is among the best-known zhelestids, with significant parts of the dentition, dermatocranium and basicranium now known (Archibald & Averianov, 2012). Because M 3 is undiscovered for Aspanlestes, character 29 was scored for Parazhelestes mynbulakensis (Nessov, 1985). Lipotyphla Haeckel, 1866: Whereas the dentition of Horolodectes provides little indication of a potential relationship with lipotyphlans, the less specialized dentition of Ferrequitherium shows broad similarities with those of various putative lipotyphlans from the Palaeocene, particularly those that have been classified in the Erinaceomorpha (hedgehog-like lipotyphlans; sensu Novacek et al., 1985; McKenna & Bell, 1997; but see the contrasting opinion of: Penkrot & Zack, 2016). The teeth of Litocherus Gingerich, 1983 and Litolestes Jepsen, 1930, particularly the lower fourth premolar, resemble those of Ferrequitherium, and the two former genera were included on that account, with Litocherus being potentially among the basalmost erinaceomorphs, and Litolestes being potentially the earliest erinaceid (see Novacek et al., 1985; O’Leary et al., 2013). Characters were scored for Litocherus notissimus (Simpson, 1936) and Litolestes ignotus Jepsen, 1930. In addition to Litocherus and Litolestes, the genus Diacocherus Gingerich, 1983 was also included in the analysis: Diacocherus has been considered a basal erinaceomorph (e. g. Krishtalka, 1976 a; Novacek, 1982, 1985; Novacek et al., 1985; Butler, 1988), although its status, both as a genus distinct from Adunator Russell, 1964, and as a lipotyphlan, continues to be debated (Krishtalka, 1976 a; Gingerich, 1983; Secord, 2008; Hooker & Russell, 2012; Rose, Storch & Krohmann, 2015). Dental characters were scored for D. meizon Gingerich, 1983. Finally, the genus Leptacodon Matthew & Granger, 1921 was included in order to test for potential broader lipotyphlan affinities, exclusive of Erinaceomorpha. Scoring decisions for Leptacodon were based on L. munusculum Simpson, 1935, a relatively well-known species that is considered to be among the basalmost members of Nyctitheriidae Simpson, 1928 (see Manz & Bloch, 2015). Analytical protocol Four heuristic parsimony analyses were performed in PAUP 4.0 a (Swofford, 2002) using the random addition sequence option; default conditions were used for all other heuristic search options. Multistate characters were unordered and multistate terminals were considered polymorphic. PAUP 4.0 a was also used to perform bootstrap analyses (default conditions) and to calculate Bremer support. Uncertainty with respect to the nearest relative of the ingroup and conflicting character states among potential outgroups prompted the decision to run separate analyses, with the resulting trees examined for any congruence in topology. The inclusion of Zhelestidae as part of the ingroup poses several difficulties for outgroup choice: zhelestids were once considered near-relatives of ungulates (e. g. Archibald, 1998; Nessov et al., 1998; Archibald et al., 2001), but subsequent analyses have positioned the family outside of Placentalia and, in some cases, basal to several stem eutherians, including Kennalestes Kielan-Jaworowska, 1969 and Maelestes Wible, Novacek, Rougier & Asher, 2007 (e. g. Wible et al., 2009; Archibald & Averianov, 2012). On the contrary, more recent large-scale analyses of many of the relevant taxa included in this analysis recover Zhelestidae crownward of Kennalestes and Maelestes (Hooker, 2014; Penkrot & Zack, 2016). Given these uncertainties, three analyses were run, each with a different outgroup. In the first analysis, the Late Cretaceous therian Prokennalestes trofimovi Kielan-Jaworowska & Dashzeveg, 1989 served as the outgroup; Prokennalestes has in previous analyses been consistently recovered stemward of the ingroup taxa included here, including Zhelestidae (e. g. Wible et al., 2009). The second and third analyses included the Late Cretaceous therian Kennalestes gobiensis and the Late Cretaceous therian Maelestes gobiensis, respectively, as outgroups. Given the uncertain phylogenetic position of Zhelestidae relative to Kennalestes and Maelestes, two subanalyses were performed with each outgroup in order to examine the effects of including or excluding Zhelestidae from the ingroup. Four characters (78 – 81) were excluded from the subanalyses where Zhelestidae were excluded, as states for these characters were rendered either invariable for all taxa, or invariable in the ingroup. A fourth analysis was performed using Prokennalestes, Kennalestes and Maelestes together in order to examine the effects of multiple outgroups on the resulting topology. Character states were optimized using the DELTRAN option, a criterion that favours convergence over reversal.	en	Scott, Craig S. (2019): Horolodectidae: a new family of unusual eutherians (Mammalia: Theria) from the Palaeocene of Alberta, Canada. Zoological Journal of the Linnean Society 185: 431-458, DOI: 10.1093/zoolinnean/zly040
