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Molar morphology and occlusion of the Early Jurassic mammalia form Erythrotherium parringtoni

100%

Jager K. R. K., Gill P. G., Martin T., Corfe I. J.

Acta Palaeontologica Polonica

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2022

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tom 67

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nr 4

2

Placental nature of the alleged marsupial from the Cretaceous of Madagascar

100%

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

Acta Palaeontologica Polonica

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2003

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tom 48

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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.

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Ankle structure in Eocene pholidotan mammal Eomanis krebsi and its taxonomic implications

100%

Horovitz I., Storch G., Martin T.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 3

Georges Cuvier (1798) established the classical concept of Edentata which included sloths, anteaters, armadillos, aardvarks, and pangolins. With the growing body of comparative morphological data becoming available during the nineteenth century, it was evident that Cuvier's “Edentata” was an artificial group (e.g., Huxley 1872). In his classical textbook, Weber (1904) excluded aardvarks and pangolins from the Edentata and put them in separate orders, Tubulidentata and Pholidota. Later on, fossil taxa were repeatedly added to and removed from Edentata, such as various xenarthran groups, taeniodonts, palaeanodonts, and gondwanatheres, but the South American Xenarthra always was considered as their core group. Even the living order Pholidota has been cited again as ?Edentata incertae sedis many years after Weber’s work (Romer 1966). The validity and extent of a higher taxon Edentata are still in dispute. In this discussion, the Middle Eocene pholidotan Eomanis and the putative xenarthran Eurotamandua from Grube Messel near Darmstadt (Germany) play an important role (Storch 1978, 1981, 2003; Rose and Emry 1993; Gaudin and Branham 1998; Rose 1999). Eomanis krebsi and Eurotamandua joresi have been subject to some discussion regarding their taxonomic distinction. It has been suggested that the only specimen known of Eo. krebsi might actually be a juvenile representative of the senior species E. joresi. A reexamination of the type specimen of Eo. krebsi has yielded some new observations regarding the identity of some of its ankle elements. An element that was previously identified as a navicular, is here reidentified as a partial distal tibia, whereas a partially exposed calcaneus had gone unnoticed. These two elements display several differences in morphology between Eo. krebsi and E. joresi, indicating that these are in fact distinct species.

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First spalacotheriid and dryolestid mammals from the Cretaceous of Germany

88%

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

Acta Palaeontologica Polonica

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2022

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tom 67

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nr 1

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A new docodont mammal from the Late Jurassic of the Junggar Basin in Northwest China

88%

Pfretzschner H.-U., Martin T., MaischM.W., Matzke A. T., Sun G.

Acta Palaeontologica Polonica

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2005

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tom 50

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nr 4

799-808

Fieldwork in the early Late Jurassic (Oxfordian) Qigu Formation of the Junggar Basin in Northwest China (Xinjiang Autonomous Region) produced teeth and mandibular fragments of a new docodont. The new taxon has a large “pseudotalonid” on the lower molars, and by retention of crest b−g exhibits closer affinities to Simpsonodon and Krusatodon from the Middle Jurassic of Europe than to the other known Asian docodonts Tashkumyrodon, Tegotherium, and Sibirotherium. It differs from the Haldanodon–Docodon−lineage by the “pseudotalonid” and large cusps b and g. A PAUP analysis based on lower molar characters produced a single most parsimonious tree with two main clades. One clade comprises Docodon, Haldanodon, and Borealestes, and the other Dsungarodon, Simpsonodon, and Krusatodon plus the Asian tegotheriids. Analysis of the molar occlusal relationships using epoxy casts mounted on a micromanipulator revealed a four−phase chewing cycle with transverse component. The molars of the new docodont exhibit a well developed grinding function besides cutting and shearing, probably indicating an omnivorous or even herbivorous diet. A grinding and crushing function is also present in the molars of Simpsonodon, Krusatodon, and the Asian tegotheriids, whereas Borealestes, Haldanodon, and Docodon retain the plesiomorphic molar pattern with mainly piercing and cutting function.

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A new relict stem salamander from the Early Cretaceous of Yakutia, Siberian Russia

76%

Skutschas P. P., Kolchanov V. V., Averianov A. O., Martin T., Schellhorn R., Kolosov P. N., Vitenko D. D.

Acta Palaeontologica Polonica

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2018

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tom 63

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nr 3

A new stem salamander, Kulgeriherpeton ultimum gen. et sp. nov., is described based on a nearly complete atlas from the Lower Cretaceous (Berriasian–Barremian) Teete vertebrate locality in southwestern Yakutia (Eastern Siberia, Russia). The new taxon is diagnosed by the following unique combination of atlantal characters: the presence of a transversal ridge and a depression on the ventral surface of the posterior portion of the centrum; ossified portions of the intercotylar tubercle represented by dorsal and ventral lips; the absence of a deep depression on the ventral surface of the anterior portion of the centrum; the absence of pronounced ventrolateral ridges; the absence of spinal nerve foramina; the presence of a pitted texture on the ventral and lateral surfaces of the centrum and lateral surfaces neural arch pedicels; the presence of a short neural arch with its anterior border situated far behind the level of the anterior cotyles; moderately dorsoventrally compressed anterior cotyles; and the absence of a deep incisure on the distal-most end of the neural spine. The internal microanatomical organization of the atlas is characterized by the presence of a thick, moderately vascularized cortex and inner cancellous endochondral bone. The recognition of stem salamanders and other vertebrates with Jurassic affinities in the Early Cretaceous high-latitude (paleolatitude estimate N 63–70°) vertebrate assemblage of Teete suggests that: (i) the large territory of present day Siberia was a refugium for Jurassic relicts; (ii) there were no striking differences in the composition of high-latitude Yakutian and mid-latitude Western Siberian Early Cretaceous vertebrate assemblages; and (iii) there was a smooth transition from the Jurassic to Cretaceous biotas in North Asia.

Ograniczanie wyników

6 Acta Palaeontologica Polonica

6 Martin T.

3 Averianov A. O.

1 Archibald J. D.

1 Corfe I. J.

1 Gill P. G.

1 Horovitz I.

1 Jager K. R. K.

1 Kolchanov V. V.

1 Kolosov P. N.

1 MaischM.W.

1 Matzke A. T.

1 Pfretzschner H.-U.

1 Schellhorn R.

1 Schultz J. A.

1 Schwermann A. H.

1 Shellhorn R.

1 Skutschas P. P.

1 Storch G.

1 Sun G.

1 Vitenko D. D.

2 2022

1 2018

2 2005

1 2003

Molar morphology and occlusion of the Early Jurassic mammalia form Erythrotherium parringtoni

Placental nature of the alleged marsupial from the Cretaceous of Madagascar

Ankle structure in Eocene pholidotan mammal Eomanis krebsi and its taxonomic implications

First spalacotheriid and dryolestid mammals from the Cretaceous of Germany

A new docodont mammal from the Late Jurassic of the Junggar Basin in Northwest China

A new relict stem salamander from the Early Cretaceous of Yakutia, Siberian Russia