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Wednesday, September 25th, 2024
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| 3:34a | [Entomology • 2024] Apatetica angusticollis • A New Species and some new distribution records of the Genus Apatetica Westwood (Coleoptera: Staphylinidae: Apateticinae) from China
Abstract Five species of Apatetica Westwood, 1848 from China are recorded and illustrated: Apatetica angusticollis sp. nov. from Sichuan, A. confusa Assing, 2018 from Yunnan, A. intermedia Cameron, 1930 from Sichuan, A. laevicollis Fauvel, 1904 from Guangdong and Guangxi, and A. sikkimi Fauvel, 1895 from Xizang. The last four are new to China. The new species is described, and a photograph of a living specimen is presented. Apatetica intermedia and A. sikkimi are redescribed and diagnosed. A key to Chinese species of the genus is provided. Key words: Apateticinae, Guangdong, Guangxi, identification key, Oriental region, Sichuan, Xizang, Yunnan
Apatetica angusticollis Chang, Schillhammer & Tang, sp. nov. 狭领脊葬隐翅虫 Diagnosis: The new species can be recognized among all known congeners with metallic elytra by the combination of the following characters: antennae and most of the legs reddish brown, pronotum with anterior margin narrower than head, and elytra with obtuse lateral apical angles. Etymology: The specific epithet is an adjective composed of the Latin adjective angustus (narrow) and the Latin noun collum (the neck). It alludes to the narrow anterior margin of the pronotum. Jin-Kang Chang, Harald Schillhammer and Liang Tang. 2024. A New Species and some new distribution records of the Genus Apatetica Westwood from China (Coleoptera, Staphylinidae, Apateticinae). ZooKeys. 1212: 65-77. DOI: doi.org/10.3897/zookeys.1212.130072 | ||||||
| 2:29p | [Paleontology • 2024] Labocania aguillonae • A New Tyrant Dinosaur (Theropoda: Tyrannosauridae) from the Late Campanian of Mexico Reveals a Tribe of Southern Tyrannosaurs
Abstract The end of the Cretaceous saw the Western Interior Seaway divide North America into two land masses, Laramidia in the west and Appalachia in the east. Laramidian dinosaurs inhabited a narrow strip of land extending from Mexico to Alaska. Within this geographically restricted area, dinosaurs evolved high diversity and endemism, with distinct species in the north and south. Here, we report a new tyrannosaurid from the Late Campanian-aged Cerro del Pueblo Formation of Coahuila, Mexico, which is part of a tribe of tyrannosaurs originating in southern Laramidia. Phylogenetic analysis recovers the new tyrannosaur as part of a clade including Labocania anomala from the La Bocana Roja Formation of Baja California Norte, Bistahieversor sealeyi from the Kirtland Formation of New Mexico, Teratophoneus curriei from the Kaiparowits Formation in Utah, and Dynamoterror dynastes from the Menefee Formation of New Mexico. Distinct frontal morphology and the younger age (~72.5–73 Ma versus >75.8 Ma for L. anomala) support recognition of the new tyrannosaur as a distinct species of Labocania, Labocania aguillonae. The Labocania clade dominated southern Laramidia at a time when the north was dominated by daspletosaurins and albertosaurines. The high endemism seen in tyrannosaurids is remarkable, given that modern apex predators have large geographic ranges and hints that the diversity of carnivorous dinosaurs has been underestimated. Keywords: Tyrannosauridae; dinosauria; Campanian; Cretaceous; Laramidia
Systematic paleontology Dinosauria—Owen 1842 Theropoda—Marsh, 1881 Coelurosauria—von Huene 1914 Tyrannosauridae—Osborn, 1906 Tyrannosaurinae—Osborn, 1906 Teratophoneini—Scherer & Voiculescu-Holvad, 2024 Labocania—Molnar 1974 Labocania aguillonae sp. nov. Diagnosis: Tyrannosaurine diagnosed by the following character combination (*—autapomorphies): orbit large and circular, with a very strongly convex anteroventral margin of the lacrimal* with a prominent, strongly dorsally extended* subocular process on the lacrimal along the anteroventral margin of the orbit; strong posteroventral extension of the antorbital fossa onto the lacrimal to end below the anterior margin of the orbit; lateral ends of frontals with a very prominent, acutely triangular shape, with strong transversely expanded overlap of frontal onto lacrimal; broad anteromedial extension of supratemporal fossa extending far forward onto frontal*; strong medial projection of postorbitals behind frontals onto dorsolateral surface of postorbital process, such that frontal underlaps the postorbital anteriorly*, lateral teeth with a figure-eight basal cross-section, and deep, prominent grooves or fullers extending from the root up the labial and lingual surfaces of the crown. Etymology: The species name honors Martha C. Aguillón, discoverer of the specimen and a long-time career paleontologist of Coahuila.  Conclusions: CPC 2974 represents a new species of tyrannosaurid, Labocania aguillonae, closely related to Labocania anomala, Bistahieversor sealeyi, and Teratophoneus curriei. It adds to the diversity of the Cerro del Pueblo Formation and shows that endemicity existed within tyrannosaurs in the Late Campanian, with distinct species and clades inhabiting the northern Great Plains in the north and the American Southwest and Mexico in the south. Given the limited geographic sampling, many tyrannosaur species likely remain undiscovered. Competition between species likely helped to enforce endemism among dinosaurs. Why large dinosaurs seem to have such unusually high levels of endemism compared to modern mammals remains unclear.  Héctor E. Rivera-Sylva and Nicholas R. Longrich. 2024. A New Tyrant Dinosaur from the Late Campanian of Mexico Reveals a Tribe of Southern Tyrannosaurs. Foss. Stud. 2024, 2(4), 245-272. DOI: doi.org/10.3390/fossils2040012 www.mdpi.com/2813-6284/2/4/12 |
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