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Friday, February 11th, 2022
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| 8:19a | [Herpetology • 2022] Tylototriton daloushanensis • A New Species of the Genus Tylototriton (Urodela: Salamandridae) from the Eastern Dalou Mountains in Guizhou, China
A new newt species, Tylototriton daloushanensis Zhou, Xiao & Luo, sp. nov., is described from Guizhou, China, based on phylogenetic and morphological analyses. Phylogenetic analyses based on mitochondrial 16S and ND2 genes show that the new species is an independent lineage closely related to T. maolanensis, T. broadoridgus, T. dabienicus, T. anhuiensis, and T. wenxianensis. Morphologically, the new species is distinguished from its congeners by a combination of the following morphological characters: (1) large body size (SVL 64.7-83.6 mm in male and 70.5-100.3 mm in female); (2) head longer than wide, prominent bony ridges present; (3) snout rounded in dorsal view; (4) tail length less than snout-vent length in both males and females; (5) dark black body coloration, except for bright orange cranial region, palms and soles, vent region, and ventral ridge of tail; (6) relative length of toes III > IV > II > I > V; (7) fingertips reaching to between the eyes and nostrils when the forelimbs are stretched forward; (8) distal tip of the limbs greatly overlapping when the fore and hind limbs are pressed along the trunk; (9) presence of gular fold; (10) vertebral ridge slightly segmented, slightly flattened rib nodules, indistinct interspaces between rib nodules; and (11) lacking orange color markings on posterior parotoids and rib nodules. The found of the new species suggests that the species diversity of the genus Tylototriton may be underestimated. Key words: Asian knobby newts, systematics, cryptic species, taxonomy.
Tylototriton daloushanensis Zhou, Xiao & Luo, sp. nov Diagnosis. The new species is assigned to the T. wenxianensis species group of the subgenus Yaotriton based on phylogenetic analysis and on the following morphological characters: body almost black, except for the orange cranial region, palms and soles, vent region, and ventral ridge of tail (Yang et al., 2014, Fei & Ye, 2016); head longer than wide; tubercles on dorsal and ventral surfaces almost equal in size; ventral skin without transverse wrinkles; and indistinct interspaces between rib nodules Etymology. The specific epithet, daloushanensis, is in reference to the type locality, Mt. Dalou in Guizhou Province, China. For the common name, we suggest “Mt. Dalou’s Knobby Newt,” and for the Chinese name, “Da Lou Shan You Yuan (大娄山疣螈).”
Tao Luo, Shasha Yan, Ning Xiao, Wei Li , Huaiqing Deng and Jiang Zhou. 2022. A New Species of the Genus Tylototriton (Amphibia: Urodela: Salamandridae) from the Eastern Dalou Mountains in Guizhou, China. Zoological Systematics. 47(1): 66-88. DOI: 10.11865/zs.2022102  | ||||||
| 10:20a | [Paleontology • 2022] Confractosuchus sauroktonos • Abdominal Contents reveal Cretaceous Crocodyliforms ate Dinosaurs
Highlights: • Description of a new early-branching eusuchian from Australia. • New taxon named Confractosuchus sauroktonos gen. et sp. nov. • Tomography scans revealed its last meal was a juvenile ornithopod dinosaur. • Morphometric analysis identifies Confractosuchus as a macro-generalist. Abstract Crocodylians are among Earth’s most successful hyper-carnivores, with their crocodyliform ancestors persisting since the Triassic. The diets of extinct crocodyliforms are typically inferred from distinctive bite-marks on fossil bone, which indicate that some species fed on contemporaneous dinosaurs. Nevertheless, the most direct dietary evidence (i.e. preserved gut contents) of these interactions in fossil crocodyliforms has been elusive. Here we report on a new crocodyliform, Confractosuchus sauroktonos gen. et sp. nov., from the Cenomanian (92.5–104 Ma) of Australia, with exceptionally preserved abdominal contents comprising parts of a juvenile ornithopod dinosaur. A phylogenetic analysis recovered Confractosuchus as the sister taxon to a clade comprising susisuchids and hylaeochampsids. The ornithopod remains displayed clear evidence of oral processing, carcass reduction (dismemberment) and bone fragmentation, which are diagnostic hallmarks of some modern crocodylian feeding behaviour. Nevertheless, a macro-generalist feeding strategy for Confractosuchus similar to extant crocodylians is supported by a morphometric analysis of the skull and reveals that dietary versatility accompanied the modular assembly of the modern crocodylian bauplan. Of further interest, these ornithopod bones represent the first skeletal remains of the group from the Winton Formation, previously only known from shed teeth and tracks, and may represent a novel taxon. Keywords: Confractosuchus sauroktonos, crocodyliform, crocodylians, morphometrics, Winton Formation, Cretaceous, ornithopod, stomach contents
Systematic Palaeontology Crocodyliformes Hay 1930 Mesoeucrocodylia Whetstone & Whybrow 1983 Neosuchia Benton & Clark 1988 Eusuchia Huxley 1875 Confractosuchus gen. nov. Confractosuchus sauroktonos gen. et sp. nov. Diagnosis: Neosuchian with the following autapomorphies: two pairs of longitudinal ridges on the rostrum that appear to span the prefrontal and lacrimal bones and terminate mid-rostrum; strongly regionalised vertebral assembly consisting of incipiently procoelous cervicals (c3–5), strongly procoelous thoracics (t1–2), incipiently procoelous (t3, ?t13) and amphicoelous mid-thoracic vertebrae (t4–7, ?9–12) (Fig. 2). Etymology: Confractus (‘broken’, Latin), referring to the shattered concretion in which the holotype was preserved, and suchus (derived from the Greek, Soûkhos), referring to the Egyptian crocodile god Sobek; sauros (‘lizard’, Greek), a common word used as a suffix for dinosaur genera, and ktonos (‘killer’ Greek) referring to its abdominal contents.     Conclusion: Here, we have described a new crocodyliform, Confractosuchus sauroktonos gen. et sp. nov., from the Winton Formation of central Queensland Australia. Its last meal, a juvenile ornithopod dinosaur, was discovered in its abdominal cavity. These gut contents oddly represent the first recorded skeletal remains of ornithopods from the Winton Formation and may represent a novel taxon. The abdominal contents provided a unique opportunity to verify predictions of feeding behaviour, ascertained from a morphometric analysis of the skull. The prediction of Confractosuchus as a macro-generalist or, at the very least a generalist feeder via GM was substantiated by the ornithopod it consumed. Matt A. White, Phil R. Bell, Nicolás E. Campione, Gabriele Sansalone, Tom Brougham, Joseph J. Bevitt, Ralph E. Molnar, Alex G. Cook, Stephen Wroe and David A. Elliott. 2022. Abdominal Contents reveal Cretaceous Crocodyliforms ate Dinosaurs. Gondwana Research. In Press. DOI: 10.1016/j.gr.2022.01.016 |
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