taxonID	type	description	language	source
0391904FFFFBFFA7F6D7FF7739D6FCFF.taxon	type_taxon	Type genus: Prochydorus Smirnov, 1992.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA7F6D7FF7739D6FCFF.taxon	diagnosis	Emended diagnosis: Body high, head capsule well developed, durable, covered with a head shield. Post-cephalic body covered with valves. Antenna II relatively long (length of basal segment + exopod = about half body length), both branches three-segmented, antennal formula (4 – 7) – (1) – (3) / (1) – (1) – (3). Gut not convoluted. Differential diagnosis: Unique antenna II (with lateral setae only on proximal segment of endopod) differentiates the family Prochydoridae from any other family in the known orders of the Cladocera.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA7F6D2FCE93EC9FB0B.taxon	materials_examined	Type (sole) species: Prochydorus rotundus Smirnov, 1992.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA7F6D2FCE93EC9FB0B.taxon	diagnosis	Diagnosis: Body very high (in life, animal was probably globular in shape), with postero-dorsal angle well expressed, head massive, with head capsule of the ‘ daphniid’ type (not compressed dorso-ventrally), valves without marginal setae, antenna II relatively short, mandible attached to valve margin.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	description	(FIGS 1 A, B, 2 A – H, 3 A – C)	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	materials_examined	Type locality: Khotont. The northern part of Mount Ukra, 6 km west of Khotont Somon in the valley of the Orkhon, north-eastern Hangay, Arhangay Aimag, Mongolia. More than 1500 impressions of different insects were collected from this locality (Rasnitsyn & Quicke, 2002).	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	discussion	Age: The absolute age of this locality was not estimated, but its palaeofauna consists of both Jurassic and Cretaceous taxa, and the age is estimated as near the Jurassic – Cretaceous boundary (Rasnitsyn & Quicke, 2002).	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	materials_examined	Holotype: PIN, 4307 / 2024 and 2040 (impression and counter-impression). Paratypes: PIN 4307 / 2019, 2020, 2025, 2038, 2039 (counter-impression of 19). The current condition of Smirnov’s (1992 a) paratype 4307 / 2020 prevents accurate determination. Impression 4307 / 2017, also listed by the author as a paratype of P. rotundus, may belong to Archeoxus mirabilis. Other material studied: PIN 4307 / 2002, 2007, 2013, 2016, 2032 (counter-impression of 13), 2041.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	diagnosis	Diagnosis: As for the genus.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	description	Description: Body very high (height / length = 0.83 – 0.92), rounded in lateral view, dorsum regularly convex, postero-dorsal angle well defined, posteroventral portion broadly rounded. Head about 0.4 ¥ body length, massive, head capsule of the ‘ daphniid-type’, with head shield supplied with a distinct fornix, rostrum pointed. Valve ventral margin without denticles or setae. Postabdomen with claw supplied with minute denticles. Antenna II short. Exopod length 0.21 – 0.25 ¥ body length, its proximal segment large, longer than 2 + 3 segments. Endopod somewhat shorter than exopod, its proximal segment only somewhat longer than second segment. Antennal formula (5) – (1) – (3) / (1) – (1) – (3). A short spine on apical segment of exopod. Mandible small, mandibular joint (Figs 2 G, 3 B: maj) located on valve margin (Figs 2 G, 3 B: vam), at a distance from point where margins of head and valve come together (Figs 2 G, 3 B: phv), instead of being attached to head shield (Figs 2 G, 3 B: hsm). Length 2.0 – 2.5 mm.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	discussion	Comments: The animal may have been subglobular in shape, as are the extant chydorids Chydorus Rak and Indialona (Smirnov & Timms, 1983; Smirnov, 1996; Kotov, 2000).	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFBFFA2F693FABF3E33F9C5.taxon	materials_examined	A specimen (PIN 4307 / 2031) from Khotont possessed unusual features. Unfortunately, its postero-dorsal half is not preserved. The animal, about 2.1 mm in length, has a high body and head of Prochydorus - type, with type of mandibular joint unknown. Each left and right antenna II has formula (?) – (1) – (1) – (1) – (1) – (1) – (?) – (?) / (1) – (1) – (3). Most probably, it is an atypical specimen of Prochydorus, with the large proximal segment of antennal exopod subdivided into six small ‘ segments’, each with a single seta. The structure of antenna II may be an atypical recapitulation to an ancestral ‘ conchostracan-like’ state. If the specimen is not atypical, it belongs to a new, undescribed order of the branchiopods instead of Prochydorus.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F698F9F33920FE22.taxon	type_taxon	Type species: Archeoxus mirabilis Smirnov, 1992.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F698F9F33920FE22.taxon	diagnosis	Diagnosis: Body moderately high with postero-dorsal angle ill defined or completely absent, head capsule of ‘ chydorid-type’ (strongly compressed dorso-ventrally), head shield with acute rostrum, valves without marginal setae, antenna II relatively long, mandible attached to point of joint of head shield and valve.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA0F503F88A3EFAFC71.taxon	description	(FIGS 1 F, 3 G, H)	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA0F503F88A3EFAFC71.taxon	materials_examined	Holotype: PIN 4307 / 2027.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA0F503F88A3EFAFC71.taxon	description	Description: Body elongated, subovoid (height / length = about 0.6) if not deformed in the holotype. Antennal formula (5) – (1) – (3) / (1) – (1) – (3). Gut not convoluted, especially wide. Length about 2 mm.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA0F503F88A3EFAFC71.taxon	discussion	Comments: Preservation of specimen PIN 4307 / 2027 is insufficient for its accurate description. It is provisionally placed in the genus Archeoxus. The species is probably a member of the Prochydoridae, but no diagnostic traits of generic rank except for the elongated body and relatively long antenna II are seen.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	description	(FIGS 1 D – E, 4 A – H)	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	description	Smirnov, 1992 a: 112, figs 1 A – C, 2 A, B, 4 A, F, 9 C, 12 A, F Type locality: Khotont, Jurassic – Cretaceous boundary (see above). Holotype: PIN 4307 / 2028 and 2036 (impression and counter-impression). Paratypes: PIN 4307 / 2001, 2007, 2011, 2012, 2015, 2023 and PIN 4307 / 2033. The recent state of Smirnov’s (1992 a) paratypes PIN 4307 / 2006, 2010, 2034 and 2037 is too poor for their accurate determination. Other material studied: PIN 4307 / 2007 - 2 (an impression on the same rock fragment with paratype 2007), 2018, 2041, 2047. Diagnosis: As for the genus. Description: Body moderately high (height / length = 0.72 – 0.79), subovoid in lateral view, dorsum regularly convex, postero-dorsal angle ill defined or absent. Head about 0.4 ¥ body length, head capsule of the ‘ chydorid-type’, covered with a ‘ flat’ head shield, with thin, pointed rostrum. Valve ventral margin without denticles or setae. Postabdominal claw supplied with denticles. Antenna II relatively long. Exopod length 0.32 – 0.35 body length, its proximal segment large, with length approximately as length of 2 + 3 segments. Endopod somewhat shorter than exopod, its proximal segment somewhat longer than second segment. Antennal formula (4 – 5) – (1) – (3) / (1) – (1) – (3). Mandible small, mandibular joint located exactly at the point where margins of head and the well-chitinized valves come together. In specimens where the head and valve were separated, the mandibular joint remained associated with valve (Fig. 4 B). Gut thin, not convoluted (Fig. 4 A). Length 2.0 – 2.9 mm. ‘ ARCHEOXUS ’ VENTROSUS SMIRNOV, 1992 (FIGS 1 F, 3 G, H) Smirnov, 1992 a: 113, figs 4 G, H, 14 A – B Type locality: Khotont, Jurassic – Cretaceous boundary (see above). Holotype: PIN 4307 / 2027. Description: Body elongated, subovoid (height / length = about 0.6) if not deformed in the holotype. Antennal formula (5) – (1) – (3) / (1) – (1) – (3). Gut not convoluted, especially wide. Length about 2 mm. Comments: Preservation of specimen PIN 4307 / 2027 is insufficient for its accurate description. It is provisionally placed in the genus Archeoxus. The species is probably a member of the Prochydoridae, but no diagnostic traits of generic rank except for the elongated body and relatively long antenna II are seen.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	materials_examined	Type locality: Khotont, Jurassic – Cretaceous boundary (see above). Holotype: PIN 4307 / 2028 and 2036 (impression and counter-impression). Paratypes: PIN 4307 / 2001, 2007, 2011, 2012, 2015, 2023 and PIN 4307 / 2033. The recent state of Smirnov’s (1992 a) paratypes PIN 4307 / 2006, 2010, 2034 and 2037 is too poor for their accurate determination. Other material studied: PIN 4307 / 2007 - 2 (an impression on the same rock fragment with paratype 2007), 2018, 2041, 2047.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	diagnosis	Diagnosis: As for the genus.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	description	Description: Body moderately high (height / length = 0.72 – 0.79), subovoid in lateral view, dorsum regularly convex, postero-dorsal angle ill defined or absent. Head about 0.4 ¥ body length, head capsule of the ‘ chydorid-type’, covered with a ‘ flat’ head shield, with thin, pointed rostrum. Valve ventral margin without denticles or setae. Postabdominal claw supplied with denticles. Antenna II relatively long. Exopod length 0.32 – 0.35 body length, its proximal segment large, with length approximately as length of 2 + 3 segments. Endopod somewhat shorter than exopod, its proximal segment somewhat longer than second segment. Antennal formula (4 – 5) – (1) – (3) / (1) – (1) – (3). Mandible small, mandibular joint located exactly at the point where margins of head and the well-chitinized valves come together. In specimens where the head and valve were separated, the mandibular joint remained associated with valve (Fig. 4 B). Gut thin, not convoluted (Fig. 4 A). Length 2.0 – 2.9 mm.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	description	(FIGS 1 F, 3 G, H)	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	materials_examined	Holotype: PIN 4307 / 2027.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	description	Description: Body elongated, subovoid (height / length = about 0.6) if not deformed in the holotype. Antennal formula (5) – (1) – (3) / (1) – (1) – (3). Gut not convoluted, especially wide. Length about 2 mm.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFEFFA2F514FE6E3827F93D.taxon	discussion	Comments: Preservation of specimen PIN 4307 / 2027 is insufficient for its accurate description. It is provisionally placed in the genus Archeoxus. The species is probably a member of the Prochydoridae, but no diagnostic traits of generic rank except for the elongated body and relatively long antenna II are seen.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFCFFA0F706FC553E25F9C0.taxon	type_taxon	Type (sole) species: Palaeorak scherbakovi sp. nov.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFCFFA0F706FC553E25F9C0.taxon	etymology	Etymology: The name of the new genus comes from Greek Palaeo (ancient), and Rak, the generic name of a chydorid with blunt rostrum and well-developed setae on the ventral margin of the valve, described by Smirnov & Timms (1983). The name Rak is derived from the Russian word (rak) for a crustacean.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFCFFA0F706FC553E25F9C0.taxon	diagnosis	Diagnosis: Body moderately high, head capsule of ‘ chydorid-type’ (compressed dorso-ventrally), covered with ‘ flat’ head shield with rostrum truncated, valves with denticles and short setae along ventral margin of valves, mandible attached to point of joint of head shield and valve.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFCFFA0F706FC553E25F9C0.taxon	discussion	Comments: The genus is probably a few million years younger than Prochydorus and Archeoxus.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
0391904FFFFCFFA0F6D5F9C23FCEF88F.taxon	materials_examined	Type locality: Khasurty. Outcrops at Khasurty River, 10 km south of Tsakir, Zakamensk District, Buryat Autonomous Republic, Asian Russia. Based on palaeofauna analysis, the Mesozoic water body represented by these sediments was reconstructed as a small mountain lake surrounded by a forest composed of different plants (D. E. Scherbakov, pers. comm.). Age: Glushkov Formation, probably, earliest Cretaceous. This recently discovered locality is poorly studied. Among fossil insects, characteristic Cretaceous taxa are more prevalent than Jurassic taxa (D. E. Scherbakov, pers. comm.). Etymology: The species is dedicated to Dr D. E. Scherbakov (PIN), who found micro-crustacean impressions on rock fragments from Khasurty. Holotype: An impression of a specimen in lateral position, 2.5 mm in length, in the collection of the Palaeontological Institute of Russian Academy of Sciences, PIN 5026 / 178. Paratypes: 97 relatively well-preserved specimens on 22 rock fragments, PIN 5026 / 89 - 177, 179 - 186 (each number is the access number for each specimen, rather than each rock fragment). Description: Body subovoid in lateral view, moderately high (height / length = 0.71 – 0.79), highest point of dorsum greatly prominent under head level, postero-dorsal angle well defined, postero-ventral angle widely rounded. Head about one-third body length, covered with a ‘ flat’ head shield, which ends proximally in a blunt rostrum. In some specimens there is a shallow depression at the posterior border of head, which may be a result of specimen deformation. The valve ventral margin is supplied with small denticles and short marginal setae (preserved only in some specimens). The postabdomen is supplied with a pair of elongated, slightly curved terminal claws, their incurved (dorsal) side armed with small denticles, but lacking a basal spine. Antenna I was not found. Antenna relatively long, about half body length or longer, its basal segment long, exopod 0.33 – 0.38 body length. Both exopod and endopods with proximal segments very long, longer than two following segments. Antennal formula (5 – 7) – (1) – (3) / (1) – (1) – (3). No spines were found on any segments. Mandibles relatively small, attached at body where head and valve join (instead of attached to the head shield in chydorids). Limbs are not distinct. Size 1.8 – 3.0 mm. Comments: In contrast to Khotont, only one fossilized cladoceran, P. scherbakovi sp. nov., was found in Khasurty.	en	Kotov, Alexey A. (2009): A revision of the extinct Mesozoic family Prochydoridae Smirnov, 1992 (Crustacea: Cladocera) with a discussion of its phylogenetic position. Zoological Journal of the Linnean Society 155 (2): 253-265, DOI: 10.1111/j.1096-3642.2008.00412.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2008.00412.x
