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Early Eocene mimotonids of Kyrgyzstan and the problem of Mixodontia

100%

Averianov A. O.

Acta Palaeontologica Polonica

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1994

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tom 39

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nr 4

393-411

2

New Late Cretaceous mammals of southern Kazakhstan

100%

Averianov A. O.

Acta Palaeontologica Polonica

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1997

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tom 42

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nr 2

Mammalian remains from the lower part of the Darbasa Formation (lower Campanian) at the 'Grey Mesa' locality in the Alymtau Range, southern Kazakhstan, are described. They include ?Bulganbaatar sp. (Multituberculata), Deltatheridium nessovi, sp. n. (Deltatheroida), and four eutherians: an undeterminated ?otlestid kennalestoid (?Otlestidae), ?Alymlestes sp. (Zalambdalestidae), ?Aspanlestes sp. (Zhelestidae), and an undeterminated eutherian. This new Cretaceous fauna is most similar to that from the Djadokhta Formation in Mongolia and may tentatively confirm an early Campanian age for the latter.

3

Early Cretaceous symmetrodont mammal Gobiotheriodon from Mongolia and the classification of Symmetrodonta

100%

Averianov A. O.

Acta Palaeontologica Polonica

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2002

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tom 47

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nr 4

The “symmetrodont” mammal, Gobiotheriodon infinitus (Trofimov, 1980), from the Early Cretaceous (Aptian–Albian) of Mongolia, is redescribed.The species is restricted to the holotype only (dentary with three last molars), the referred maxillary fragment with M3? is considered here as cf. Gobiconodon sp.The dental formula of G. infinitusis reinterpreted as i1–3 c1 p1–3 m1–4. G. infinitus is characterized by a short dentary symphysis; long, well−developed Meckel's groove; small, triangular−shaped pterygoid fossa; weakly developed pterygoid crest; i3 enlarged; p1–3 two−rooted; lower molars acute− to obtuse−angled, labial cingulids lacking, lingual cingulids very short, well developed mesial and distal cingulid cuspules (“e” and “d”) and prominent wear surface on the paracristid. Gobiotheriodon is similar to Tinodon (Late Jurassic, USA; Early Cretaceous, Great Britain and Portugal) in postcanine dental formula and structure of the pterygoid fossa; it is provisionally assigned to Tinodontidae Marsh, 1887.Some taxa previously assigned to (or suggested as possible relatives of) “Symmetrodonta” are reviewed.Amphidontidae Simpson, 1925 is considered as nomen dubium.A new classification for “Symmetrodonta” is proposed.

4

New material and reinterpretation of the Late Cretaceous eutherian mammal Paranyctoides from Uzbekistan

63%

Averianov A. O., Archibald J. D.

Acta Palaeontologica Polonica

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2013

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tom 58

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nr 1

Paranyctoides aralensis, based on a partially known set of lower postcanines from the Turonian Bissekty Formation of Uzbekistan, is proposed to be a junior subjective synonym of Sailestes quadrans, itself based on an M1 from the same stratigraphic unit. As a result, the latter taxon is recombined as Paranyctoides quadrans comb. nov. Based on newly col− lected or recognized specimens, we show that this species has four lower incisors, including a procumbent i1 and a rela− tively small i4, as well as five double−rooted premolars, the smallest of which (p3) can be lost ontogenetically. The p5 of this species is premolariform, rather than molariform as previously thought based on an erroneous identification, and re− sembles North American species of Paranyctoides in the presence of a small, cingulid−like paraconid and a distal talonid cusp, as well as the absence of a metaconid. The lower molars of Paranyctoides are unique among Late Cretaceous eutherians in having a larger, lingually placed paraconid. Paranycoides probably is the sister taxon of the Late Cretaceous Zhelestidae.

5

Albanerpetontid amphibians from the Upper Cretaceous of Middle Asia

63%

Gardner J. D., Averianov A. O.

Acta Palaeontologica Polonica

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1998

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tom 43

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nr 3

453-476

We review the fossil record of Asian albanerpetontids. The three dentaries previously attributed to the two species of Nukusurus Nessov, 1981 (lower Cenomanian and Coniacian, Uzbekistan) are from albanerpetontids, but none are distinctive below the familial level. We thus designate the names Nukusurus, N. insuetus Nessov, 1981, and N. sodalis Nessov, 1997 as nomina dubia within the Albanerpetontidae. Two dentaries (lower Cenomanian, Uzbekistan) described herein for the first time supplement the known record of Asian albanerpetontids. The holotype atlas and only specimen of the supposed albanerpetontid Bishara backa Nessov, 1997 (upper Santonian-?Campanian, Kazakhstan) is shown to be from a salamander, not an albanerpetontid. Our study recognizes Albanerpeton (Cretaceous-Miocene, North America and Europe) and Celtedens (Middle Jurassic-Lower Cretaceous, Europe) as the only valid albanerpetontid genera. Limited evidence favors one or more dispersals from Europe or Norttr America to Asia in the medial Cretaceous as the major biogeographic event in the history of Asian albanerpetontids.

6

Sauropod diversity in the Upper Cretaceous Nemegt Formation of Mongolia - a possible new specimen of Nemegtosaurus

63%

Averianov A. O., Lopatin A. V.

Acta Palaeontologica Polonica

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2019

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tom 64

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nr 2

Currently, there are two sauropod taxa known from the Upper Cretaceous (Maastrichtian) Nemegt Formation of Gobi Desert, Mongolia: Nemegtosaurus from the Nemegt locality and Opisthocoelicaudia from the Altan Uul IV locality. Both taxa are represented by not overlapping elements (skull and partial postcranial skeleton respectively), which arises question on their possible synonymy. Five articulated sauropod dorsal vertebrae (PIN 3837/P821, dorsals 6–10) were found in 1949 by the Mongolian Expedition of the Academy of Sciences of the USSR at the Nemegt locality. This specimen is similar to Opisthocoelicaudia in having a strong ventral ridge on dorsal centra, a low neural arch which is anteroposteriorly narrowest at the junction with the centrum and widens dorsally, and lack of hyposphene–hypantrum articulations. PIN 3837/P821 differs from Opisthocoelicaudia by having the less dorsoventrally flattened dorsal centra, a shallow ventral concavity of dorsal centra in lateral view, a vertical posterior centrodiapophyseal lamina (pcdl) in dorsals 8 and 9, a postzygodiapophyseal lamina (podl) that roofs the centrodiapophyseal fossa (pocdf), and strongly developed accessory laminae within the parapophyseal centrodiapophyseal fossa (pacdf). The sauropod femora from Nemegt Formation differ from the femur of Opisthocoelicaudia by the medial condyle extending more distally compared with the lateral condyle. Most likely these femora and PIN 3837/P821 belong to Nemegtosaurus, which would make this taxon distinct from Opisthocoelicaudia by discussed characters of dorsal vertebrae and femur

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New diplodocoid sauropod dinosaur material from the Middle Jurassic of European Russia

63%

Averianov A. O., Zverkov N. G.

Acta Palaeontologica Polonica

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2020

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tom 65

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nr 3

8

Paranyctoides and allies from the Late Cretaceous of North America and Asia

63%

Archibald J. D., Averianov A. O.

Acta Palaeontologica Polonica

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2001

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tom 46

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nr 4

Paranyctoides is represented by three named, and possibly four unnamed species in the Late Cretaceous, North America. P. aralensis from the Late Cretaceous of Dzharakuduk, Uzbekistan, belongs in this or a closely allied taxon. Lower molars have low trigonids, well-developed paraconids not appressed against metaconids, talonids on ml-2 as wide or wider than trigonids, hypoconulids often closer to entoconids than to hypoconids. Only two upper molars are known, both have comparatively narrow crowns with wide stylar shelves and stylar cusps, paracone and metacone separated, conules well developed, and protocone low. Pre- and postcingula vary from narrow in one, Sailestes quadrans, to wide in the other, Paranyctoides sp. Sailestes quadrans may be an metatherian. All known species of Paranyctoides from North America have a submolarifom ultimate premolar while Gallolestes pachymandibularis, also from North America, has molars not unlike those in Paranyctoides but may have an ultimate premolar with a molarifom trigonid. A specimen from Dzharakuduk referable to P. aralensis is suggestive of such morphology. At least P. aralensis had five premolars with the third reduced as in 'zhelestids'. These findings increase the Late Cretaceous North American/Asian ties even more for eutherians, now with 'zhelestids' and the Paranyctoides/Gallolestes clades known from both.

9

A new genus of eutherian mammal from the Early Cretaceous of Transbaikalia, Russia

63%

Averianov A. O., Skutschas P. P.

Acta Palaeontologica Polonica

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2001

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tom 46

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nr 3

10

New specimens of the multituberculate mammal Uzbekbaatar from the Late Cretaceous of Uzbekistan

63%

Averianov A. O., Archibald J. D.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 2

Uzbekbaatar Kielan−Jaworowska and Nessov, 1992 is among the rarest mammals and the only multituberculate in the diverse, eutherian dominated Bissekty (Turonian) and Aitym (?Coniacian) local faunas, Kyzylkum Desert, Uzbekistan. New material from the Bissekty local fauna, suggests that only one multituberculate species, Uzbekbaatar kizylkumensis Kielan−Jaworowska and Nessov, 1992 is present in the Bissekty fauna. A newly collected p4 is better preserved than the holotype and demonstrates presence of the posterolabial cusp in the p4 of Uzbekbaatar. New material of Uzbekbaatar is consistent with placement of this taxon within the basal cimolodontan “Paracimexomys group.”

11

Femur of a morganucodontid mammal from the Middle Jurassic of Central Russia

63%

Gambaryan P. P., Averianov A. O.

Acta Palaeontologica Polonica

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2001

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tom 46

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nr 1

We describe a nearly complete mammalian femur from the Middle Jurassic (upper Bathonian) from Peski quarry, situated some 100 km south east of Moscow, central Russia. It is similar to the femora of Morganucodontidae in having a globular femoral head, separated from the greater trochanter and reflected dorsally, fovea capitis present, both trochanters triangular and located on the same plane, distal end flat, mediolaterally expanded, and somewhat bent ventrally, and in the shape and proportions of distal condyles. It is referred to as Morganucodontidae gen. et sp. indet. It is the first representative of this group of mammals in Eastern Europe from the third Mesozoic mammal locality discovered in Russia. Exquisite preservation of the bone surface allowed us to reconstruct partial hind limb musculature. We reconstruct m. iliopsoas as inserting on the ridge, which starts at the lesser trochanter and extends along the medial femoral margin for more than half of the femur length. On this basis we conclude that the mode of locomotion of the Peski morganucodontid was similar to that of modern echidnas. During the propulsive phase the femur did not retract and the step elongation was provided by pronation of the femur.

12

Late Cretaceous asioryctitherian eutherian mammals from Uzbekistan and phylogenetic analysis of Asioryctitheria

63%

Archibald J. D., Averianov A. O.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 2

Four small asioryctitheres at Dzharakuduk (Turonian), Uzbekistan are Daulestes kulbeckensis (= Kumlestes olzha), D. inobservabilis (= Kennalestes? uzbekistanensis), Uchkudukodon (gen. nov.) nessovi and Bulaklestes kezbe. Uchkudukodon nessovi is one of the smallest therians (molars about 1 mm long). Lower canine is two−rooted in Uchkudukodon gen. nov. and Bulaklestes(uncertain in Daulestes). All lower premolars in all four species are double−rooted. Teeth identified as dp1, p2 and dp2 in holotype of Uchkudukodon nessovi (McKenna et al. 2000) are here identified c, p1, and p2. A phylogenetic analysis weakly supported Asioryctitheria by four synapomorphies: conular basins become distinct, the number of roots reverts to two on the lower canine, the p5 becomes longer than p4, and the metaconid on p5 is reduced and lost. Other characters diagnostic of asioryctitheres are four upper and lower premolars (arguably five upper premolars in juvenile Kennalestes), P4 has a protocone swelling or protocone, some asymmetry of the stylar shelf on M1–2, the paraconule on M1–3 is distinctly closer to the protocone than is the metaconule, protocone is of moderate height on M1–3 (70–80% of paracone or metacone height), Meckel’s groove is absent, and the mandibular foramen opens into a smaller depression on lingual side of mandibular ascending ramus. Asioryctes and Ukhaatherium are placed in Asioryctinae and along with Kennalestes are placed in Asioryctidae. Kennalestidae Kielan−Jaworowska, 1981 is a junior subjective synonym for Asioryctidae Kielan−Jaworowska, 1981. Because of uncertainties in the analysis, the positions of Daulestes, Uchkudukodon gen. nov., and Bulaklestes cannot be determined beyond referral to Asioryctitheria.

13

Annamite striped rabbit Nesolagus timminisi in Vietnam

51%

Can D. N., Abramov A. V., Tikhonov A. N., Averianov A. O.

Acta Theriologica

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2001

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tom 46

|

nr 4

437-440

The distribution of a new species of striped rabbit Nesolagus timminsi Averianov, Abramov et Tikhonov, 2000 is restricted to the central part of the Annamite Mountains, along the border between Vietnam and Laos. A low density of separated populations and hunting pressure in Vietnam already makes this species critically endangered.

14

A new soft-shelled trionychid turtle of the genus Khunnuchelys from the Upper Cretaceous Bostobe Formation of Kazakhstan

51%

Danilov I. G., Vitek N. S., Averianov A. O., Glinskiy V. N.

Acta Palaeontologica Polonica

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2015

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tom 60

|

nr 1

Previously unpublished trionychid turtle material from the Upper Cretaceous (Santonian–lower Campanian) Bostobe Formation from the Baybishe and Baykhozha localities in Kazakhstan is described. The material represents a new species of Khunnuchelys, a large, skull-based clade of Cretaceous Asian trionychids. Concordant with other partial skulls and fragmentary specimens described previously, Khunnuchelys lophorhothon sp. nov. has the unusual features of a beaklike maxilla and a vaulted, expanded triturating surface. In addition, the specimens reveal novel features including a constricted skull roof. Although estimates of the length of the carapace differ depending on estimation method, the skull belonged to a turtle of comparable size to the shell-based species “Trionyx” kansaiensis from the same formation. It is likely that K. lophorhothon and “T.” kansaiensis are synonymous, but this can be proved only by a find of associated skull and shell material.

15

Petrosal bones of placental mammals from the Late Cretaceous of Uzbekistan

51%

Ekdale E. G., Archibald J. D., Averianov A. O.

Acta Palaeontologica Polonica

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2004

|

tom 49

|

nr 1

Petrosal bones representing “Zhelestidae” and Kulbeckia (“Zalambdalestidae”) were recovered from the Late Cretaceous of Uzbekistan and are formally described. The “zhelestid” petrosal retains several characters ancestral to eutherians (if not more basally in the mammalian phylogeny),including a prootic canal,a lateral flange,and a less elliptical fenestra vestibuli. The only other eutherian taxon to retain these structures is the Early Cretaceous Prokennalestes. No characters unique to “zhelestids” and ungulates were found in the “zhelestid” petrosal. The petrosal of Kulbeckia shares several characters in common with other “zalambdalestids” (such as Zalambdalestes and Barunlestes),as well as Asioryctes and Kennalestes,including a curved ridge connecting the crista interfenestralis to the caudal tympanic process,and presence of a “tympanic process” at the posterior aspect of the petrosal.

16

Placental nature of the alleged marsupial from the Cretaceous of Madagascar

51%

Averianov A. O., Archibald J. D., Martin T.

Acta Palaeontologica Polonica

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2003

|

tom 48

|

nr 1

A recently (Krause 2001) reported fragmentary mammalian lower molar (University of Antananarivo, UA 8699) from the Late Cretaceous (Maastrichtian) of Madagascar, was attributed to Marsupialia, for which far reaching paleobiogeographical conclusions were made. The five characters used to identify UA 8699 as a marsupial are not exclusive to Late Cretaceous marsupials, but are found also in some placental mammals, notably in Late Cretaceous ungulatomorph zhelestids, known from various Upper Cretaceous strata in Asia, Europe, and NorthAmerica (Nessov et al. 1998). Identification of UA 8699 as a zhelestid placental is in keeping withmyriad other faunal similarities between Europe and Africa/Madagascar.

17

Two bone fragments of ornithocheiroid pterosaurs from the Cenomanian of Volgograd region, Southern Russia

51%

Averianov A. O., Kurochkin E. N., Pervushov E. M., Ivanov A. V.

Acta Palaeontologica Polonica

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2005

|

tom 50

|

nr 2

Two pterosaur bone fragments, a distal humerus and a distal femur, from the upper Cenomanian of the Volgograd Region in the Don River basin of southern Russia are reported. Although fragmentary, these bones come from mature individuals and are exceptionally well and three−dimensionally preserved, allowing a detailed description of their anatomy. Both specimens can be referred to a middle−sized ornithocheiroid pterosaur with a reconstructed wingspan of about 4 m. The humerus shows affinities with Istiodactylus from the Barremian of England, whereas the femur fragment is not identifiable beyond Ornithocheiroidea indet.

18

Mammalian distal humeri from the Late Cretaceous of Uzbekistan

45%

Chester S. G. B., Sargis E. J., Szalay F. S., Archibald J. D., Averianov A. O.

Acta Palaeontologica Polonica

|

2010

|

tom 55

|

nr 2

199-211

We describe mammalian distal humeri recovered from the Bissekty Formation, Dzharakuduk, Kyzylkum Desert, Uzbekistan (90 Ma). Isolated elements were sorted into groups that likely correspond to species (or genera). These groups were allocated to taxa known mostly from the dentition, petrosals, and/or tarsals at this site. We identified one humerus of a multituberculate and one of a zalambdalestid. Several eutherian humeri have been tentatively assigned to Zhelestidae based on their dissimilarity to zalambdalestids and the abundance of zhelestids in the dental record. The zalambdalestids and zhelestids were probably terrestrial. At least two metatherian taxa have also been identified, and both were likely arboreal. Although the dental record suggests twelve eutherian species and only one metatherian, crurotarsal evidence supports the presence of at least four metatherian species at Dzharakuduk. The humeri analyzed here also provide support for the presence of multiple metatherians in the fauna, further demonstrating that postcrania are critical to understanding the taxonomic diversity present at these Late Cretaceous localities.

19

First spalacotheriid and dryolestid mammals from the Cretaceous of Germany

45%

Martin T., Averianov A. O., Schultz J. A., Shellhorn R., Schwermann A. H.

Acta Palaeontologica Polonica

|

2022

|

tom 67

|

nr 1

20

Therian femora from the Late Cretaceous of Uzbekistan

45%

Chester S. G. B., Sargis E. J., Szalay F. S., Archibald J. D., Averianov A. O.

Acta Palaeontologica Polonica

|

2012

|

tom 57

|

nr 1

Femora referable to metatherians and eutherians recovered from the Bissekty Formation, Dzharakuduk, Kyzylkum Desert, Uzbekistan (90 Mya), are described. Fourteen isolated specimens were sorted based on size and morphology into groups that likely correspond to the species level or higher. Groups were then tentatively assigned to taxa known from teeth, petrosals, and/or other postcrania at these localities. One distal femur of a small arboreal metatherian, and several eutherian distal femora that probably represent zhelestids and/or zalambdalestids were identified. With the exception of one proximal femur that is similar in some aspects to the zalambdalestid Barunlestes, and a previously described multituberculate specimen, all other proximal femora from the Bissekty Formation exhibit a metatherian−like morphology. The dental record currently suggests the presence of twelve eutherian species and only one metatherian at Dzharakuduk, whereas the humeral and crurotarsal evidence supports the presence of at least two or four metatherian species, respectively. Given the sample size of the proximal femora, the morphological diversity present, and the overwhelming presence of eutherians at these localities, it is highly unlikely that the overwhelming majority of proximal femora actually represent metatherians. Therefore, this sample may suggest that the metatherian proximal femoral condition is primitive for Theria and that some eutherian taxa (probably including Zhelestidae, which are dentally most abundant at these localities) retain this condition.

Ograniczanie wyników

Early Eocene mimotonids of Kyrgyzstan and the problem of Mixodontia

New Late Cretaceous mammals of southern Kazakhstan

Early Cretaceous symmetrodont mammal Gobiotheriodon from Mongolia and the classification of Symmetrodonta

New material and reinterpretation of the Late Cretaceous eutherian mammal Paranyctoides from Uzbekistan

Albanerpetontid amphibians from the Upper Cretaceous of Middle Asia

Sauropod diversity in the Upper Cretaceous Nemegt Formation of Mongolia - a possible new specimen of Nemegtosaurus

New diplodocoid sauropod dinosaur material from the Middle Jurassic of European Russia

Paranyctoides and allies from the Late Cretaceous of North America and Asia

A new genus of eutherian mammal from the Early Cretaceous of Transbaikalia, Russia

New specimens of the multituberculate mammal Uzbekbaatar from the Late Cretaceous of Uzbekistan

Femur of a morganucodontid mammal from the Middle Jurassic of Central Russia

Late Cretaceous asioryctitherian eutherian mammals from Uzbekistan and phylogenetic analysis of Asioryctitheria

Annamite striped rabbit Nesolagus timminisi in Vietnam

A new soft-shelled trionychid turtle of the genus Khunnuchelys from the Upper Cretaceous Bostobe Formation of Kazakhstan

Petrosal bones of placental mammals from the Late Cretaceous of Uzbekistan

Placental nature of the alleged marsupial from the Cretaceous of Madagascar

Two bone fragments of ornithocheiroid pterosaurs from the Cenomanian of Volgograd region, Southern Russia

Mammalian distal humeri from the Late Cretaceous of Uzbekistan

First spalacotheriid and dryolestid mammals from the Cretaceous of Germany

Therian femora from the Late Cretaceous of Uzbekistan