Dermotherium
Dermotherium Temporal range:
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Dermoptera |
Family: | Cynocephalidae |
Genus: | †Dermotherium Ducrocq et al., 1992 |
Type species | |
†Dermotherium major Ducrocq et al., 1992
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Other species | |
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Dermotherium is a
Some features of the teeth differentiate Dermotherium from both living colugo species, but other features are shared with only one of the two. The third lower
Taxonomy
In 2006, Laurent Marivaux and colleagues described a second species of Dermotherium, D. chimaera, from material from the
Description
Known material of Dermotherium includes a handful of jaw fragments and isolated teeth. Dermotherium major is known only from a fragment of the left lower jaw bearing the third lower molar (m3) and a poorly preserved second lower molar (m2).
The two species of Dermotherium were about as large as the Philippine colugo and larger than the Sunda colugo and differed from both in several characteristics of the dentition.[12] Not enough is known of the skeleton of Dermotherium to assess whether the animal already possessed the gliding adaptations of living colugos.[13] The two species are similar in size, but again differ in details of the dentition.[14] In two specimens of D. chimaera, the length and width of the m2 are 5 and 4.3 mm (0.20 and 0.17 in) and 5.4 and 4.8 mm (0.21 and 0.19 in) respectively; this tooth is 5.4 mm (0.21 in) long and 4.9 mm (0.19 in) wide in the only known specimen of Dermotherium major. The Pakistani M2 of Dermotherium is 4.3 mm (0.17 in) long and 6 mm (0.24 in) wide, compared to 4.7 and 6.6 mm (0.19 and 0.26 in) in the only known M2 of D. chimaera from Thailand.[15]
The lower jaw of Dermotherium major resembles that of living colugos in the presence of a strong
Lower dentition
The i3 of Dermotherium chimaera is an elongate tooth bearing six tines (narrow, high "fingers" as in a comb) arranged from front to back. The frontmost is larger, the next four are about equal in size, and the sixth is smaller.
In Dermotherium chimaera, the p4 and m1 through m3 are similar to each other (and unlike the i3, canine, and p3) and appear to form a series of decreasing size from front to back.
The talonid contains a hypoconid, hypoconulid, and
Upper dentition
The upper molars of Dermotherium chimaera are triangular in overall shape and much broader than long, with the narrow end of the triangle pointing lingually.
Range and ecology
Dermotherium major was found in a
Fossils of Dermotherium chimaera come from
The specializations of dermopterans are such that they are dependent on a forested habitat,[36] and reconstructions of the paleoenvironments at Krabi, Nong Ya Plong, and Paali Nala suggest that all three fossil deposits developed in a humid, tropical forest environment.[37] Their extinction in the Indian subcontinent may have been caused by the development of a drier climate there during the Late Oligocene.[38]
References
- ^ Stafford 2005; Marivaux et al. 2006, p. 396; Janečka et al. 2007.
- ^ Marivaux et al. 2006, p. 396.
- ^ Ducrocq et al. 1992, pp. 373–374.
- ^ Stafford & Szalay 2000, p. 378.
- ^ Silcox et al. 2005, p. 131.
- ^ a b Marivaux et al. 2006, p. 400.
- ^ Marivaux et al. 2006, pp. 405–406.
- ^ Marivaux et al. 2006, fig. 11.
- ^ a b Ducrocq et al. 1992, pp. 374–375.
- ^ Marivaux et al. 2006, p. 400, fig. 3.
- ^ a b c d e f g h i Marivaux et al. 2006, p. 405.
- ^ Marivaux et al. 2006, pp. 398–399, 404.
- ^ Marivaux et al. 2006, pp. 414–415.
- ^ Marivaux et al. 2006, p. 400, table 1.
- ^ Marivaux et al. 2006, table 1.
- ^ Marivaux et al. 2006, p. 400, fig. 4.
- ^ Marivaux et al. 2006, pp. 404–405.
- ^ Marivaux et al. 2006, pp. 400–401, fig. 4.
- ^ Marivaux et al. 2006, pp. 401–402, fig. 4.
- ^ Ungar 2010, p. 190.
- ^ a b c d Marivaux et al. 2006, p. 403.
- ^ Ducrocq et al. 1992, p. 375.
- ^ a b c Marivaux et al. 2006, pp. 402–403, figs. 4, 5.
- ^ Marivaux et al. 2006, pp. 403, 405.
- ^ a b Marivaux et al. 2006, p. 403, fig. 6.
- ^ a b c Marivaux et al. 2006, p. 406.
- ^ a b Marivaux et al. 2006, p. 404.
- ^ Marivaux et al. 2006, pp. 403–404, fig. 6.
- ^ a b Marivaux et al. 2006, p. 404, fig. 6.
- ^ Marivaux et al. 2006, pp. 404, 406.
- ^ Ducrocq et al. 1992, p. 373.
- ^ Peigné et al. 2009, p. 991; Benammi et al. 2001, pp. 266–267; Marivaux et al. 2006, p. 425.
- ^ Benammi et al. 2001, p. 265; Marivaux et al. 2006, p. 426.
- ^ Marivaux et al. 2006, pp. 400, 414; Peigné et al. 2009, pp. 975–976.
- ^ Welcomme et al. 2001, p. 398.
- ^ Marivaux et al. 2006, pp. 412–413.
- ^ Marivaux et al. 2006, p. 414; Marivaux et al. 2006, p. 426; Ducrocq et al. 1995, p. 67.
- ^ Marivaux et al. 2006, p. 414.
Literature cited
- Benammi, M.; Chaimanee, Y.; Jaeger, J.; Suteethorn, V.; Ducrocq, S. (2001). "Eocene Krabi basin (southern Thailand): Paleontology and magnetostratigraphy". Geological Society of America Bulletin. 113 (2): 265–273. .
- Ducrocq, S.; Buffetaut, E.; Buffetaut-Tong, H.; Jaeger, J.-J.; Yongkanjanasoontorn, Y.; Suteethorn, V. (1992). "First fossil flying lemur: A dermopteran from the Late Eocene of Thailand" (PDF). Palaeontology. 35 (2): 373–380. Archived from the original (PDF) on 2011-09-19.
- Ducrocq, S.P.; Chaimanee, Y.; Suteethorn, V.; Jaeger, J.-J. (1995). "Mammalian faunas and the ages of the continental Tertiary fossiliferous localities from Thailand". Journal of Southeast Asian Earth Sciences. 12 (1–2): 65–78. .
- Janečka, J.E.; Miller, W.; Pringle, T.H.; Wiens, F.; Zitzmann, A.; Helgen, K.M.; Springer, M.S.; Murphy, W.J. (2007). "Molecular and genomic data identify the closest living relative of primates" (PDF). Science. 318 (5851): 792–794. S2CID 12251814.
- Marivaux, L.; Bocat, L.; Chaimanee, Y.; Jaeger, J. -J.; Marandat, B.; Srisuk, P.; Tafforeau, P.; Yamee, C.; Welcomme, J. -L. (2006). "Cynocephalid dermopterans from the Palaeogene of South Asia (Thailand, Myanmar and Pakistan): Systematic, evolutionary and palaeobiogeographic implications". Zoologica Scripta. 35 (4): 395–420. S2CID 86572864.
- Marivaux, L.; Chaimanee, Y.; Tafforeau, P.; Jaeger, J.-J. (2006). "New strepsirrhine primate from the late Eocene of Peninsular Thailand (Krabi Basin)". American Journal of Physical Anthropology. 130 (4): 425–434. PMID 16444732.
- Peigné, S.; Chaimanee, Y.; Yamee, C.; Marandat, B.; Srisuk, P.; Jaeger, J.-J. (2009). "An astonishing example of convergent evolution toward carnivory: Siamosorex debonisi n. gen., n. sp. (Mammalia, Lipotyphla, Soricomorpha, Plesiosoricidae) from the latest Oligocene of Thailand" (PDF). Geodiversitas. 31 (4): 973–992. S2CID 129885681.
- Silcox, M.T.; Bloch, J.I.; Boyer, D.M.; Sargis, E.J. (2005). "Euarchonta (Dermoptera, Scandentia, Primates)". In Rose, K.D.; Archibald, J.D (eds.). The Rise of Placental Mammals. Baltimore: Johns Hopkins University Press. pp. 127–144. ISBN 978-0-8018-8022-3.
- Stafford, B.J. (2005). "Order Dermoptera". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore: Johns Hopkins University Press. p. 110. ISBN 978-0-8018-8221-0.
- Stafford, B.J.; Szalay, F.S. (2000). "Craniodental functional morphology and taxonomy of dermopterans". Journal of Mammalogy. 81 (2): 360–385. S2CID 86052722.
- Ungar, P.S. (2010). Mammal Teeth: Origin, Evolution, and Diversity. Baltimore: Johns Hopkins University Press. p. 304. ISBN 978-0-8018-9668-2.
- Welcomme, J.-L.; Benammi, M.; Crochet, J.-Y.; Marivaux, L.; Métais, G.; Antoine, P.-O.; Baloch, I. (2001). "Himalayan Forelands: palaeontological evidence for Oligocene detrital deposits in the Bugti Hills (Balochistan, Pakistan)". Geological Magazine. 138 (4): 397–405. S2CID 129800812.