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Wednesday, March 2nd, 2022
| Time | Event | ||||
| 5:48a | [Arachnida • 2021] Weygoldtia hainanensis • A New Species of Whip Spider (Amblypygi: Charinidae) from Hainan, China
Abstract To date, only one species of whip spider has been recorded in China. Here, we describe a new species, Weygoldtia hainanensis sp. nov., from Hainan, China. The new species is morphologically similar to W. davidovi (Fage, 1946) and W. consonensis Miranda et al. 2021, but can be distinguished with a combination of the following characters: 26 segments in tibia I, 6-7 teeth on chelicerae, distitibia IV trichobothria sc and sf series each with 10-11 trichobothria. To validate our morphological inferences and support the erection of W. hainanensis sp. nov. as a new species, we sequenced the COI gene region for two individuals and performed molecular phylogenetic analyses. The inferred phylogenetic trees placed the new species within Weygoldtia and highlighted the evolutionary distinction between W. hainanensis sp. nov. and currently described whip spiders. The type specimens are deposited in the Museum of Biology, East China Normal University (ECNU). Keywords: Arachnida, taxonomy, biodiversity, karst, Island
Weygoldtia hainanensis Zhu, Li & He sp. nov. Xiao-Yu Zhu, Shi-Yang Wu, Yi-Jiao Liu, Chris R. Reardon, Cristian Román-Palacios, Zheng Li and Zhu-Qing He. 2021. A New Species of Whip Spider, Weygoldtia hainanensis sp. nov., from Hainan, China (Arachnida: Amblypygi: Charinidae). Zootaxa. 5082(1); 65-76. DOI: 10.11646/zootaxa.5082.1.6 | ||||
| 11:26a | [Paleontology • 2022] Kelumapusaura machi • A New Hadrosaurid (Ornithischia: Hadrosauridae) from the Late Cretaceous of northern Patagonia and the Radiation of South American Hadrosaurids
Abstract Here we describe a new hadrosaurid from the Upper Cretaceous (Campanian–Maastrichtian) Allen Formation of Río Negro Province, north-west Patagonia. The new taxon is based on cranial and postcranial elements from subadult and adult specimens. The new taxon may have reached 8–9 m in total body length, and it is diagnosed by a unique combination of characters, including a very low maxilla with respect to the dentary, and a dentary with a prominent and elongate anterior process with a deep groove on its anterior end, among other features. The new taxon is known from well-preserved elements and constitutes one of the most complete hadrosaurids known from South America. Features of the teeth, cranial and postcranial bones of the new taxon overlap with those of other hadrosaurid specimens previously recorded from this continent. This new evidence allows us to recognize that Secernosaurus koerneri, Bonapartesaurus rionegrensis and ‘Kritosaurus’ australis are valid taxa. The latter can be distinguished from the other South American taxa, as well as from Kritosaurus from North America. Thus, a new generic name is proposed for the species ‘Kritosaurus’ australis. Phylogenetic analysis recovers a new clade of South American hadrosaurids composed of the new taxon, ‘Kritosaurus’ australis, Bonapartesaurus and Secernosaurus. The new South American clade is tentatively nested among Kritosaurini and is supported by several traits, including an ilium with a subhorizontal ridge separating the preacetabular notch from the pubic pedicle, a longitudinal ridge on the dorsal surface of the postacetabular process, and a twisted distal end of the postacetabular process. The recovery of a monophyletic clade of South American hadrosaurids indicates that the history of the clade on Gondwanan landmasses is far from well understood, and new discoveries may change the current picture of the taxonomy and phylogenetic relationships of southern duck-billed dinosaurs. Keywords: Hadrosauridae, Patagonia, Late Cretaceous, Secernosaurus koerneri, ‘Kritosaurus’ australis
 Superorder Dinosauria Owen, 1842 Order Ornithischia Seeley, 1887 Infraorder Ornithopoda Marsh, 1881 Family Hadrosauridae Cope, 1869 Subfamily Saurolophinae Brown, 1914 Tribe Kritosaurini Lapparent & Lavocat, 1955 Kelumapusaura machi gen. et sp. nov. Diagnosis. Kelumapusaura machi is diagnosed on the basis of the following unique combination of characters (autapomorphies marked with an asterisk): a shallow maxilla when compared with the dorsoventral height of the dentary; maxilla with a dorsoventrally low medialsurface dorsal to the medial row of foramina; maxilla with a groove forming a constriction on the anteroventral process; maxilla with a posterodorsal margin of the lateral surface forming a thick ridge that houses the palatine and pterygoid processes; postorbital with short to absent medial process on the skull roof; dentary symphysis with anteriorly oriented sub-triangular processes, ventrally delimited by a deep groove on its anterior end, resulting in a bilobate outline in lateral view; anterior-end of the dentary with a crescent-shaped concavity on its lateral surface; first sacral with anterior articular sur-faces strongly anterodorsally facing and obliquely oriented; scapula with a longitudinal groove dorsal to the acromial process; proportionally narrow scapular neck, being 0.5 times the dorsoventral length of the proximal-end; and scapula with a nearly straight (or weakly arched) scapular blade. Etymology. The root of the generic name, ‘Kelumapu’, means ‘red earth’ in the Mapudungun language. The specific name ‘machi’ refers to the shaman of the Mapuche people. Huallasaurus gen. nov. Etymology. The generic name ‘Hualla’ means ‘duck’ inthe Mapudungun language. Type and only included species. Huallasaurus australis comb. nov. Sebastián Rozadilla, Federico Brissón-Egli, Federico Lisandro Agnolín, Alexis Mauro Aranciaga-Rolando and Fernando Emilio Novas. 2022. A New Hadrosaurid (Dinosauria: Ornithischia) from the Late Cretaceous of northern Patagonia and the Radiation of South American Hadrosaurids. Journal of Systematic Palaeontology. DOI: 10.1080/14772019.2021.2020917  |
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