1991 in paleontology

Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils.^[1] This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1991.

List of years in paleontology (table)
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In science 1988 1989 1990 1991 1992 1993 1994
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Plants

Angiosperms

Name	Novelty	Status	Authors	Age	Unit	Location	Notes	Images
Cruciptera[2]	Gen et comb nov	valid	Brown	Middle Eocene	Clarno Formation	USA  Oregon	A walnut relative. Moved from Tetrapteris simsoni (1940)[3]
Soleredera[4]	Gen et sp nov	Valid	Erwin & Stockey	Eocene Ypresian	Okanagan Highlands Princeton Chert	Canada  British Columbia	A lilialean genus of uncertain placement

Arthropods

Insects

Name	Novelty	Status	Authors	Age	Unit	Location	Notes	Images
Anochetus brevidentatus[5]	Sp nov	Valid	MacKay	Burdigalian	Dominican amber	Dominican Republic	A ponerin ant
Stenolestes hispanicus[6]	Sp nov	Valid	Nel	Vallesian	Bellver de Cerdanya	Spain	A sieblosiid damselfly	Stenolestes hispanicus

Mollusca

Newly named bivalves

Name	Novelty	Status	Authors	Age	Unit	Location	Notes	Images
Similodonta wahli[7]	Sp nov	Valid	Isakar	Late Ordovician	Arina Formation	Estonia

Archosauromorphs

• Sankar Chatterjee's discovery of a possible Triassic bird, Protoavis, if genuine, would push avian origins back almost 70 million years. The find ignites controversy over the connection between dinosaurs and birds.

Newly named dinosaurs

Data courtesy of George Olshevsky's dinosaur genera list.^[8]

Name	Status	Authors	Age	Unit	Location	Notes	Images
Alvarezsaurus[9]	Valid taxon	Jose Bonaparte	Late Cretaceous (Santonian)	Bajo de la Carpa Formation	Argentina	An alvarezsaurid.	Alvarezsaurus
Amargasaurus[10]	Valid taxon	Salgado and Jose Bonaparte	Early Cretaceous (Barremian)	La Amarga Formation	Argentina	A dicraeosaurid. with Spines on its Neck	Amargasaurus
Amurosaurus[11]	Valid taxon	Bolotsky & Kurzanov	Late Cretaceous (Maastrichtian)	Udurchukan Formation	Russia  China	A lambeosaurine hadrosaurid.
Andesaurus[12]	Valid taxon	Calvo and Bonaparte	Late Cretaceous (Santonian)	Bajo de la Carpa Formation	Argentina	An alvarezsaurid.
Becklespinax[13]	Junior synonym	George Olshevsky.	Early Cretaceous (Valanginian)	Wadhurst Clay Formation	UK	A junior objective synonym of Altispinax; new genus for "Acrocanthosaurus" altispinax Paul (1988).
Euronychodon[14]	Valid taxon	Telles-Antunes & Sigogneau-Russell	Late Cretaceous (Maastrichtian)		Portugal  Uzbekistan	A troodontid.
Janenschia[15]	Valid taxon	Wild	Late Jurassic (Kimmeridgian-Tithonian)	Tendaguru Formation	Tanzania	A non-titanosauriform macronarian; new genus for "Gigantosaurus" robustus E. Fraas (1908).
Protognathosaurus[13]	Valid taxon	George Olshevsky	Middle Jurassic (Bajocian)	Xiashaximiao Formation	China	A sauropod of uncertain affinities.
"Rioarribasaurus"[16]	Junior synonym	Hunt & S.G. Lucas	Late Triassic (late Norian-Rhaetian)			A junior synonym of Coelophysis.
"Seismosaurus"[17]	Junior synonym	Gillette
Tarascosaurus[18]	Valid taxon	Le Loeuff and Buffetaut			France
Taveirosaurus[14]	Valid taxon	Telles-Antunes & Sigogneau-Russell	Late Cretaceous		Portugal  Spain	An ornithischian of unknown affinities.
Tochisaurus[19]	Valid taxon	Kurzanov and Osmolska	Cretaceous		Mongolia
"Ultrasauros"[13]	Junior synonym	George Olshevsky	Late Jurassic (Kimmeridgian)	Morrison Formation		Junior synonym of Supersaurus; replacement name for Ultrasaurus Jensen 1985 (preoccupied).
Valdoraptor[13]	Valid taxon	George Olshevsky	Early Cretaceous (late Valanginian)	Tunbridge Wells Formation	UK	An ornithomimosaur; new genus for "Megalosaurus" oweni Lydekker (1889).
Velocisaurus[9]	Valid taxon	Jose Bonaparte			Argentina	A Noasaur.	Velocisaurus

Newly named birds

Name	Status	Novelty	Authors	Age	Unit	Location	Notes	Images
Aidemedia chascax [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu	USA ( Hawaii)	A Fringillidae, Carduelinae.
Aidemedia lutetiae [20]	Valid	Gen. nov. et Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Molokai	USA ( Hawaii)	A Fringillidae, Carduelinae, this is the type species of the new genus.
Aidemedia zanclops [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu	USA ( Hawaii)	A Fringillidae, Carduelinae.
Apteribis brevis [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Maui	USA ( Hawaii)	A Threskiornithidae.
Asiahesperornis bazhanovi [22]	Valid	Gen. nov. et Sp. nov.	Lev A. Nessov B. V. Prizemlin	Late Cretaceous	Late Campanian-Early Maastrichtian, Eginsai Formation	Kazakhstan	A Hesperornithiformes Fürbringer, 1888, Hesperornithidae Marsh, 1872.
Branta hylobadistes [21]	Valid	Gen. nov. et Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Maui	USA ( Hawaii)	An Anatidae.
Chelychelynechen quassus [21]	Valid	Gen. nov. et Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Kauai	USA ( Hawaii)	An Anatidae, a moa-nalo, this is the type species of the genus.
Chloridops regiskongi [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu	USA ( Hawaii)	A Fringillidae, Carduelinae.
Chloridops wahi [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu	USA ( Hawaii)	A Fringillidae, Carduelinae.
Circus dossenus [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Molokai	USA ( Hawaii)	An Accipitridae.
Ciridops tenax [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Kauai	USA ( Hawaii)	A Fringillidae, Carduelinae.
Corvus impluviatus [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu	USA ( Hawaii)	A Corvidae.
Corvus viriosus [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu	USA ( Hawaii)	A Corvidae.
Dendroscansor decurvirostris [23]	Valid	Gen. nov et Sp. nov.	Philip R. Millener Trevor H. Worthy	Late Pleistocene	Otira Glacial Age	New Zealand	An Acanthisittidae.
Grallistrix auceps [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Kauai	USA ( Hawaii)	A Strigidae.
Grallistrix erdmani [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Maui	USA ( Hawaii)	A Strigidae.
Grallistrix geleches [21]	Valid	Gen. nov. et Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Molokai	USA ( Hawaii)	A Strigidae, the type species of the new genus.
Grallistrix orion [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Oahu	USA ( Hawaii)	A Strigidae.
Hemignathus upupirostris [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Kauai	USA ( Hawaii)	A Fringillidae, Carduelinae, transferred to the genus Akialoa Olson et James, 1995 by Olson et James, 1995.[24]
Horusornis vianeyliaudae [25]	Valid	Gen. nov et Sp. nov.	Cécile Mourer-Chauviré	Late Eocene	Phosphorites du Quercy MP 17	France	An Accipitriformes, Horusornithidae Mourer-Chauviré, 1991, this is the type species of the new genus.
Orthiospiza howarthi [20]	Valid	Gen. nov et Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Maui	USA ( Hawaii)	A Fringillidae, Carduelinae, this is the type species of the new genus.
Palaeocryptonyx hungaricus [26]	Valid	Sp. nov.	Dénes Jánossy	Late Miocene	MN 13	Hungary	A Phasianidae, transferred to the genus Plioperdix Kretzoi, 1955 as Plioperdix hungarica Comb. nov. by Nikita V. Zelenkov & Andrey V. Panteleyev.[27]
Pavo aesculapi phasianoides [26]	Valid	Subsp. nov.	Dénes Jánossy	Late Miocene		Hungary	A member of the family Phasianidae. Originally described as a subspecies of Pavo aesculapi; Zelenkov (2016) transferred it to the genus Syrmaticus and raised it to the rank of a separate species Syrmaticus phasianoides.[28]
Phalacrocorax kuehneanus [29]	Valid	Sp. nov.	Thomas Schlüter	Late Pliocene	Minjingu	Tanzania	A Phalacrocoracidae.
Phoeniconaias siamensis [30]	Valid	Sp. nov.	Jacques Cheneval Léonard Ginsburg Cécile Mourer-Chauviré Benjavun Ratanasthien	Late Early Miocene	Li Mae	Thailand	A Phoenicopteridae.
Porzana estramosi veterior [26]	Valid	Subsp. nov.	Dénes Jánossy	Late Miocene		Hungary	A member of the family Rallidae. Originally described as a subspecies of Porzana estramosi; Zelenkov (2017) transferred it to the genus Zapornia and raised it to the rank of a separate species Zapornia veterior.[31]
Porzana keplerorum [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Maui	USA ( Hawaii)	A Rallidae.
Porzana menehune [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Molokai	USA ( Hawaii)	A Rallidae.
Porzana ralphorum [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Oahu	USA ( Hawaii)	A Rallidae.
Porzana severnsi [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Maui	USA ( Hawaii)	A Rallidae.
Porzana ziegleri [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Oahu	USA ( Hawaii)	A Rallidae.
Protoavis texensis [32]	Valid	Gen. nov. et Sp. nov.	Sankar Chatterjee	Late Trias	Late Carnian-Early Norian	USA ( Texas)	A Protoaviformes Chatterjee, 1991, Protoaviformes Chatterjee, 1991, the type and only species of the genus, no longer considered a bird.
Pseudodontornis tshulensis [33]	Valid	Sp. nov.	Aleksandr O. Averianov Andrei V. Panteleyev Olga R. Potapova Lev A. Nessov	Late Paleocene	Landenian	Kazakhstan	A Pseudodontornithidae Lambrecht, 1933.
Pseudoseisuropsis nehuen [34]	Valid	Gen. nov. et Sp. nov.	Jorge I. Noriega	Early Pleistocene	Miramar Formation	Argentina	A Furnariidae, Philydorinae, this is the type species of the new genus.
Ptaiochen pau [21]	Valid	Gen. nov. et Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Maui	USA ( Hawaii)	An Anatidae, a moa-nalo, this is the type species of the genus.
Pterodroma jugabilis [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Oahu	USA ( Hawaii)	A Procellariidae.
Rallicrex polgardiensis [26]	Valid	Sp. nov.	Dénes Jánossy	Late Miocene	MN 13	Hungary	A member of the family Rallidae. Originally described as a species of Rallicrex; Zelenkov (2017) transferred this species to the genus Rallus.[31]
Telespiza persecutrix [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu, Kauai	USA ( Hawaii)	A Fringillidae, Carduelinae.
Telespiza ypsilon [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Molokai, Maui	USA ( Hawaii)	A Fringillidae, Carduelinae.
Thambetochen xanion [21]	Valid	Sp. nov.	Storrs L. Olson Helen F. James	Holocene	Oahu	USA ( Hawaii)	An Anatidae, a moa-nalo.
Tyto campiterrae [26]	Valid	Sp. nov.	Dénes Jánossy	Late Miocene	MN 13	Hungary	A Tytonidae.
Vangulifer mirandus [20]	Valid	Gen. nov. et Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Maui	USA ( Hawaii)	A Fringillidae, Carduelinae.
Vangulifer neophasis [20]	Valid	Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Maui	USA ( Hawaii)	A Fringillidae, Carduelinae.
Xestospiza conica [20]	Valid	Gen. nov. et Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Kauai	USA ( Hawaii)	A Fringillidae, Carduelinae.
Xestospiza fastigialis [20]	Valid	Gen. nov. et Sp. nov.	Helen F. James Storrs L. Olson	Holocene	Oahu, Molokai, Maui	USA ( Hawaii)	A Fringillidae, Carduelinae, the type species of the new genus.

Genera no longer considered to be birds

• Protoavis. The avian status of Protoavis has since been almost universally rejected by paleontologists.

Pseudosuchians

Name	Novelty	Status	Authors	Age	Type locality	Country	Notes	Images
Australosuchus clarkae[35]	Gen. et sp. nov	Valid	Willis & Molnar	Late Oligocene - Early Miocene	Etadunna Formation	Australia	A mekosuchine crocodilian described from a multitude of skeletons.

Pterosaurs

New taxa

Name Status Authors Location Images Bennettazhia Valid Nesov  USA ( Oregon)

Synapsids

Non-mammalian

Name	Status	Authors	Age	Unit	Location	Notes	Images
Apsisaurus[36]	Valid	Laurin	Lower Permian	Archer City Formation	USA ( Texas)	Formerly assigned as an eosuchian diapsid, was restudied and classified as a varanopid synapsid.[37]	Apsisaurus
Ctenorhachis[38]	Valid	Hook Hotton	Upper Permian		USA ( Texas)	A sphenacodontid synapsid.	Ctenorhachis

References

• Paleontology portal

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2. Manchester, S.R. (1994). "Fruits and Seeds of the Middle Eocene Nut Beds Flora, Clarno Formation, Oregon". Palaeontographica Americana. 58: 30–31.
3. Brown, R. W. (1940). "New species and changes of name in some American fossil floras. Journal of the Washington Academy of Sciences". 30 (8): 344–356. JSTOR 24529454. {{cite journal}}: Cite journal requires |journal= (help)
4. Erwin, D. M.; Stockey, R. A. (1991). "Soleredera rhizomorpha gen. et sp. nov., a permineralized monocotyledon from the Middle Eocene Princeton chert of British Columbia, Canada". Botanical Gazette. 152 (2): 231–247. doi:10.1086/337885. S2CID 85180086.
5. MacKay, W. P. (1991). "Anochetus brevidentatus, new species, a second fossil Odontomachiti ant (Hymenoptera: Formicidae)". Journal of the New York Entomological Society. 99: 138–140.
6. Nel, Nel (1991). "Description de quelques Sieblosiidae fossiles nouveaux (Odonata, Zygoptera, Lestoidea). Nouvelle Revue d'Entomologie (N.S.)". 8: 367–375. {{cite journal}}: Cite journal requires |journal= (help)
7. Hints, L.; Oraspõld, A.; Kaljo, D. (2000). "Stratotype of the Porkuni Stage with comments on the Röa Member (Uppermost Ordovician, Estonia)". Proceedings of the Estonian Academy of Sciences, Geology. 49 (3): 177–199. doi:10.3176/geol.2000.3.02. S2CID 240195751.
8. Olshevsky, George. "Dinogeorge's Dinosaur Genera List". Archived from the original on 2011-07-15. Retrieved 2008-08-07.
9. Bonaparte, J.F. 1991. Los vertebrados fosiles de la Formacion Rio Colorado de Neuquen y cercanias, Cretacico Superior, Argentina. Revista del Museo Argentino de Ciencias Naturales "Bernardino Revidadia" Paleontologia 4 (3): pp. 17-23.
10. Salgado, L. and J.F. Bonaparte. 1991. Un Nuevo sauropodo Dicraeosauridae, Amargasaurus gen. et sp. nov., de la Formacion La Amarga, Neocomiano de la Provincia del Nuequen, Argentina. Ameghiniana 28: pp. 333-346.
11. Bolotsky, Yu. L. and S.K. Kurzanov. 1991. The hadrosaurs of the Amur region. In: Geology of the Pacific Border: pp.94-103.
12. Calvo, J.O. and J.F. Bonaparte, J.F. 1991. Andesaurus delgadoi gen. et sp. nov. (Saurischia-Sauropoda), dinosaurio Titanosauridae de la Formación Río Limay (Albiano-Cenomaniano), Neuquén, Argentina. Ameghiniana 28: pp. 303-310.
13. Olshevsky, G. 1991. A Revision of the Parainfraclass Archosauria Cope, 1869, Excluding the Advanced Crocodylia. Mesozoic Meanderings 2 (1st printing): iv + 196 pages.
14. Telles-Antunes, M. and D. Sigogneau-Russell, 1991. Nouvelles donnees sur les Dinosaures du Cretae superieur du Portugal. Compte rendu hebdomadaire des séances de l’Académie des Sciences Paris, tomo 313, seire 2: pp. 113-119.
15. Wild, R. 1991. Janenschia n. g. robusta (E.Frass 1908) pro Tornieria robusta (E. Fraas 1908) (Reptilia, Saurischia, Sauropodomorpha). Stuttgarteer Beiträge zur Naturkude Serie B (Geologie und Paleontologie) 173: pp. 1-4.
16. Hunt, A.P. and S.G. Lucas. 1991. Rioarribasaurus, a new name for a Late Triassic dinosaur from New Mexico (USA). Paläontologische Zeitschrift 6 (3/4): pp. 191-198.
17. Gillette. D.D. 1991. Seismosaurus halli, gen. et sp. nov., a new sauropod dinosaur from the Morrison Formation (Upper Jurassic/Lower Cretaceous) of New Mexico, USA. J. Vertebr. Paleontol. 11 (4): pp. 417-433.
18. Le Loeuff, J. and E. Buffetaut. 1991. Tarascosaurus salluvicus, new genus new species, a theropod dinosaur from the Upper Cretaceous of southern France. Geobios 24 (5): pp. 585-594.
19. Kurzanov, S.M. and H. Osmolska. 1991. Tochisaurus nemegtensis gen. et sp. n., a new troodontid (Dinosauria, Theropoda) from Mongolia. Acta Palaeont. Polonica. 36 (1): pp. 69-76.
20. Helen F. James; Storrs L. Olson (1991). "Descriptions of Thirty-Two New Species of Birds From the Hawaiian Islands: Part II. Passeriformes" (PDF). Ornithological Monographs. 46 (46): 1–88. doi:10.2307/40166713. JSTOR 40166713.
21. Storrs L. Olson; Helen F. James (1991). "Descriptions of Thirty-Two New Species of Birds From the Hawaiian Islands: Part I. Non-Passeriformes" (PDF). Ornithological Monographs. 45 (45): 1–88. doi:10.2307/40166794. JSTOR 40166794.
22. Lev A. Nessov; B. V. Prizemlin (1991). "Krupnyye evolyutsionno prodvinutyye neletayushchiye morskiye ptitsy odryada gesperornisoobraznykh pozdnego senona Turgayskogo proliva: pervyye nakhodki gruppy v SSSR [Large, Evolutionarily Advanced, Flightless Marine Birds of the Order Hesperornithiformes from the Late Senonian of the Turgai Strait: The first Finds of this Group in the USSR.] [in Russian, with English summary]". Trudy Zoologicheskogo Instituta, Akademiya Nauk SSSR. 239: 85–107.
23. Philip R. Millener; Trevor H. Worthy (1991). "Contribution to New Zealand's Late Quaternary Avifauna. II: Dendroscansor decurvirostris, a New Genus and Species of Wren (Aves: Acantisittidae)". Journal of the Royal Society of New Zealand. 21 (2): 179–200. doi:10.1080/03036758.1991.10431406.
24. Storrs L. Olson; Helen R. James (1995). "Nomenclature of the Hawaiian Akialoas and Nukupuus (Aves: Drepanidini)" (PDF). Proceedings of the Biological Society of Washington. 108 (3): 373–387.
25. Cécile Mourer-Chauviré (1991). "Les Horusornithidae Nov. Fam., Accipitriformes (Aves) A Articulation Intertarsienne Hyperflexible de l'Éocène du Quercy". Géobios, Mémoire Spécial. 24 (supplement 1): 183–192. Bibcode:1991Geobi..24Q.183M. doi:10.1016/s0016-6995(66)80023-2.
26. Dénes Jánossy (1991). "Late Miocene Bird Remains from Polgárdi (W-Hungary)". Aquila. 98: 13–35.
27. Nikita V. Zelenkov; Andrey V. Panteleyev (2015). "Three bird taxa (Aves: Anatidae, Phasianidae, Scolopacidae) from the Late Miocene of the Sea of Azov (Southwestern Russia)". Paläontologische Zeitschrift. 89 (3): 515–527. doi:10.1007/s12542-014-0238-0. S2CID 85276099.
28. Nikita V. Zelenkov (2016). "Revision of non-passeriform birds from Polgárdi (Hungary, Late Miocene): 2. Galliformes". Paleontological Journal. 50 (6): 623–634. doi:10.1134/S0031030116060162. S2CID 90727042.
29. Thomas Schlüter (1991). "Systematik, Palökologie und Biostratonomie von Phalacrocorax kuehneanus nov. spec., einem Fossilen Kormoran (Aves: Phalacrocoracidae) aus Mutmasslich Oberpliozänen Phosporiten N-Tansanias". Berliner Geowissenschaftliche Abhandlungen, Reihe A: Geologie und Paläontologie. 134: 279–309.
30. Jacques Cheneval; Léonard Ginsburg; Cécile Mourer-Chauviré; Benjavun Ratanasthien (1991). "The Miocene Avifauna of the Li Mae Long Locality, Thailand: Systematics and Palaeoecology". Journal of Southeast Asian Earth Sciences. 6 (2): 117–126. Bibcode:1991JAESc...6..117C. doi:10.1016/0743-9547(91)90103-5.
31. N. V. Zelenkov (2017). "Revision of non-passeriform birds from Polgárdi (Hungary, Upper Miocene): 3. Neoaves". Paleontological Journal. 51 (2): 203–213. doi:10.1134/S0031030117020162. S2CID 90314539.
32. Sankar Chatterjee (1991). "Cranial Anatomy and Relationships of A New Triassic Bird from Texas". Philosophical Transactions of the Royal Society of London, Series B. 332 (1265): 277–342. Bibcode:1991RSPTB.332..277C. doi:10.1098/rstb.1991.0056.
33. Aleksandr O. Averianov; Andrei V. Panteleyev; Olga R. Potapova; Lev A. Nessov (1991). "Lozhnozubyye ptitsy (Aves: Pelecaniformes: Odontopterygia) pozdnego paleotsena i eotsena zapadnoy okrainy drevney Azii. [Bony-toothed Birds (Aves: Pelecaniformes: Odontopterygia) of the Late Paleocene and Eocene of the Western Margin of Ancient Asia.] [in Russian, with English summ.]". Trudy Zoologicheskogo Instituta, Akademiya Nauk SSSR. 239: 3–12.
34. Jorge I. Noriega (1991). "Un Nuevo Género de Furnariidae (Aves: Passeriformes) del Pleistoceno Inferior-Medio de la Provincia de Buenos Aires, Argentina". Ameghiniana. 28: 317–323.
35. Willis, P.M.A. & Molnar, R.E. (1991). "A new middle Tertiary crocodile from Lake Palankarinna, South Australia". Records of the South Australian Museum. 25 (1): 39–55.
36. Laurin, M. (1991). "The osteology of a Lower Permian eosuchian from Texas and a review of diapsid phylogeny". Zoological Journal of the Linnean Society. 101: 59–95. doi:10.1111/j.1096-3642.1991.tb00886.x.
37. Reisz, R.R.; Laurin, M.; Marjanovic, D. (2010). "Apsisaurus witteri from the Lower Permian of Texas: yet another small varanopid synapsis, not a diapsid". Journal of Vertebrate Paleontology. 30 (5): 1628–1631. Bibcode:2010JVPal..30.1628R. doi:10.1080/02724634.2010.501441. S2CID 129835335.
38. Hook, R.W.; Hotton, N. (1991). "A New Sphenacodontid Pelycosaur (Synapsida) from the Wichita Group, Lower Permian of North-Central Texas". Journal of Vertebrate Paleontology. 11 (1): 37–44. Bibcode:1991JVPal..11...37H. doi:10.1080/02724634.1991.10011374.