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Functional morphology of the upper and lower eyelids, third eyelid, lacrimal gland and superficial gland of the third eyelid in the red kangaroo (Macropus rufus)

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Kleckowska-Nawrot J., Gozdziewska-Harlajczuk K., Barszcz K., Janeczek M.

Folia Biologica

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2016

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tom 64

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nr 3

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Therian femora from the Late Cretaceous of Uzbekistan

84%

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

Acta Palaeontologica Polonica

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2012

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tom 57

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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.

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A peculiar faunivorous metatherian from the early Eocene of Australia

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Beck R. M. D.

Acta Palaeontologica Polonica

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2015

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tom 60

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nr 1

I describe Archaeonothos henkgodthelpi gen. et. sp. nov., a small (estimated body mass ~40–80 g) tribosphenic metatherian from the early Eocene Tingamarra Fauna of southeastern Queensland, Australia. This taxon, known only from a single isolated upper molar (M2 or M3) is characterised by a very distinctive combination of dental features that, collectively, probably represent faunivorous adaptations. These include: a straight, elevated centrocrista; a metacone considerably taller than the paracone; a wide stylar shelf (~50% of the total labiolingual width of the tooth); reduced stylar cusps; a long postmetacrista; a small and anteroposteriorly narrow protocone; an unbasined trigon; and the absence of conules. Some of these features are seen in dasyuromorphians, but detailed comparisons reveal key differences between A. henkgodthelpi and all known members of this clade. A. henkgodthelpi also predates recent molecular estimates for the divergence of crown-group Dasyuromorphia. Similar dental features are seen in a number of other metatherians, including the South American sparassodonts, Wirunodon chanku from the ?middle–late Eocene Santa Rosa local fauna of Peru, and Kasserinotherium tunisiense from the early Eocene Chambi fauna of Tunisia, although whether A. henkgodthelpi is closely related to any of these taxa is unclear based on available evidence. I therefore refer A. henkgodthelpi to Metatheria incertae sedis. Potential relatives of A. henkgodthelpi are unknown from any other Australian fossil deposit.

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Reappraisal of the tribosphenidan mammals from the Trinity Group (Aptian-Albian) of Texas and Oklahoma

59%

Davis B. M., Cifelli R. L.

Acta Palaeontologica Polonica

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2011

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tom 56

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nr 3

The Trinity therians have long been the focus of attempts to reconstruct the evolutionary history of higher mammals, especially in the context of the development of tribospheny. In this paper, we update the taxonomy of the tribosphenidan taxa known from the Trinity Group and establish with more confidence the premolar/molar count in each. Many isolated specimens can be referred to a specific tooth locus. Additional diversity is revealed within the Deltatheroida, with the description of an additional species of Oklatheridium; Pappotherium is here considered a likely metatherian based on the inferred presence of four molars, while Holoclemensia is a basal eutherian (the opposite of some traditional interpretations). The remainder of the genera, Kermackia and Slaughteria, cannot be allied with either of the living groups of tribosphenidan mammals using the available data. We identify strong morphological diversity within this assemblage of stem taxa, including modifications to the traditional tribosphenic occlusal pattern in Kermackia. Mammalian evolution at the base of the tribosphenidan radiation was complex, and this underscores the need for caution when interpreting the morphology and relationships of taxa known by incomplete material.

Ograniczanie wyników

3 Acta Palaeontologica Polonica

1 Folia Biologica

1 Archibald J. D.

1 Averianov A. O.

1 Barszcz K.

1 Beck R. M. D.

1 Chester S. G. B.

1 Cifelli R. L.

1 Davis B. M.

1 Gozdziewska-Harlajczuk K.

1 Janeczek M.

1 Kleckowska-Nawrot J.

1 Sargis E. J.

1 Szalay F. S.

1 2016

1 2015

1 2012

1 2011

Functional morphology of the upper and lower eyelids, third eyelid, lacrimal gland and superficial gland of the third eyelid in the red kangaroo (Macropus rufus)

Therian femora from the Late Cretaceous of Uzbekistan

A peculiar faunivorous metatherian from the early Eocene of Australia

Reappraisal of the tribosphenidan mammals from the Trinity Group (Aptian-Albian) of Texas and Oklahoma