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Friday, July 21st, 2023
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| 6:07a | [Arachnida • 2023] Sadala rauli • A New Species of Spider of the Genus Sadala Simon, 1880 (Araneae: Sparassidae) from the Yasuni Biosphere Reserve, Amazonian Lowlands of Ecuador
Abstract We describe a new species of giant crab spider of the genus Sadala Simon, 1880 collected in Lowland Evergreen rainforests at the Tiputini Biodiversity Station, Yasuni Biosphere Reserve, Amazonian Ecuador. This new species corresponds to the first record of the genus from Ecuador. Females of the new species of Sadala are similar to S. punicea and S. nanay, by having the epigyne with a median septum diamond-shaped posteriorly. The new species is easily distinguished from S. punicea and S. nanay by having relatively straight anterior lateral margins of the median septum. This study increases to 10 the number of described species of Sadala. Keywords: giant crab spider, huntsman spider, new species, northern South America, taxonomy, Tiputini
Sadala rauli Peñaherrera-R. & Cisneros-Heredia, new species Generic placement. The new species is assigned to the genus Sadala by having chelicerae with three promarginal teeth and intermarginal denticles, 5–10 escort setae at the base of fang, short-toothed female palpal claw, three pairs of spines on ventral tibiae I–II, and median septum of epigyne with triangular scape-like projection (Rheims & Jäger, 2022). Diagnosis. Females of Sadala rauli sp. nov. resembles S. punicea and S. nanay by having the epigyne with a long TP, wider than long, and MS diamond-shaped posteriorly (Figures 1 and 2). The new species is easily differentiated from S. punicea and S. nanay by having relatively straight anterior lateral margins of the MS (more curved in S. punicea and S. nanay). Also, S. rauli differs from S. punicea by having a MS more than 1.5 times longer than wide with elliptical CO. Etymology. The specific name is a patronym for Victor Raul Peñaherrera de la Cadena, grandfather of Pedro Peñaherrera-R., who in life had the project of narrating the history of Ecuador in a book that could not be completed and now will form part of the natural history of Ecuador immortalized in this species.  Pedro Peñaherrera-R. and Diego F. Cisneros-Heredia. 2023. A New Species of Spider of the Genus Sadala Simon, 1880 (Araneae, Sparassidae) from the Yasuni Biosphere Reserve, Amazonian lowlands of Ecuador. Ecology and Evolution. DOI: 10.1002/ece3.10242 | ||||
| 10:13a | [Paleontology • 2022] Lepidobatrachus dibumartinez • A New Old Budgett Frog: An Articulated Skeleton of an Early Pliocene Lepidobatrachus (Anura: Ceratophryidae) from western Argentina
ABSTRACT The South American horned frogs or ‘escuerzos’ (Ceratophryidae) are among the best-known neobatrachians and comprise the genera Chacophrys, Ceratophrys, and Lepidobatrachus. Their relatively rich fossil record, which dates back to the Late Miocene and is largely concentrated in the Argentinean Pampas, consists mostly of variably complete cranial remains and comparatively few, mainly isolated, postcranial bones of Ceratophrys, whereas only three specimens of Lepidobatrachus are known. Here we describe two extra-Pampean ceratophryid records from the Upper Miocene–Lower Pliocene of Huayquerías del Este, Mendoza Province, Argentina, including Lepidobatrachus dibumartinez sp. nov. based on a well-preserved articulated skeleton. The new species is part of the stem of Lepidobatrachus and is diagnosed on the basis of several cranial and postcranial traits, including a large kite-shaped dorsal dermal shield. The new taxon sheds light on the evolution of a dorsal shield in the group, as well as on their paleobiogeographic history, adding support to the hypothesis of a broader ancestral distribution of Lepidobatrachus, whose diversification might have been triggered by the Late Miocene marine introgression of the Paranaense Sea. Also, it indicates that the prevalent climatic conditions during the Early Pliocene in western Argentina were much warmer and less dry than today. Finally, we discuss the potential value of the new records in calibrating the time-tree of Ceratophryidae. Guillermo F. Turazzini and Raúl O. Gómez. 2022. A New Old Budgett Frog: An Articulated Skeleton of an Early Pliocene Lepidobatrachus (Anura, Ceratophryidae) from western Argentina. Journal of Vertebrate Paleontology. 42(5); e2207092. DOI: 10.1080/02724634.2023.2207092  | ||||
| 10:21a | [Paleontology • 2023] Igai semkhu • A New titanosaurian (Dinosauria: Sauropoda) from the Upper Cretaceous (Campanian) Quseir Formation of the Kharga Oasis, Egypt
ABSTRACT Dinosaur fossils from the latest Cretaceous (Campanian–Maastrichtian) of Africa and the Arabian Peninsula are rare. Most discoveries to date have consisted of limited fossils that have precluded detailed phylogenetic and paleobiogeographic interpretations. Fortunately, recent discoveries such as the informative Egyptian titanosaurian sauropod dinosaur Mansourasaurus shahinae are beginning to address these long-standing issues. Here we describe an associated partial postcranial skeleton of a new titanosaurian taxon from the Upper Cretaceous (Campanian) Quseir Formation of the Kharga Oasis, Western Desert of Egypt. Consisting of five dorsal vertebrae and 12 appendicular elements, Igai semkhu gen. et sp. nov. constitutes one of the most informative dinosaurs yet recovered from the latest Cretaceous of Afro-Arabia. The relatively gracile limb bones and differences in the coracoid and metatarsal I preclude referral of the new specimen to Mansourasaurus. Both model-based Bayesian tip-dating and parsimony-based phylogenetic analyses support the affinities of Igai semkhu with other Late Cretaceous Afro-Eurasian titanosaurs (e.g., Mansourasaurus, Lirainosaurus astibiae, Opisthocoelicaudia skarzynskii), a conclusion supported by posterior dorsal vertebrae that lack a postzygodiapophyseal lamina, for example. Igai semkhu strengthens the hypothesis that northern Africa and Eurasia shared closely related terrestrial tetrapod faunas at the end of the Cretaceous and further differentiates this fauna from penecontemporaneous assemblages elsewhere in Africa, such as the Galula Formation in Tanzania, that exhibit more traditional Gondwanan assemblages. At present, the specific paleobiogeographic signal appears to vary between different dinosaur groups, suggesting that Afro-Arabian Cretaceous biotas may have experienced evolutionary and paleobiogeographic histories that were more complex than previously appreciated. DINOSAURIA Owen, 1842 SAUROPODA Marsh, 1878 TITANOSAURIA Bonaparte and Coria, 1993 LITHOSTROTIA Upchurch et al., 2004
IGAI SEMKHU gen. et sp. nov. Diagnosis— Characters supporting Igai semkhu as a titanosaurian sauropod dinosaur: dorsal vertebrae lacking hyposphene-hypantrum articulations; and ulna with prominent olecranon process. Autapomorphic characters of Igai semkhu: metacarpal V with proximomedial and distomedial tubercles; reduced cnemial crest of the tibia (does not exceed anterior margin of distal end of the tibia); and distal groove along dorsal margins of metatarsals I and II. Etymology— “Igai” is the name of the enigmatic “lord of the oasis” deity that was venerated by inhabitants of the Dakhla and Kharga oases (and surrounding regions) in Egypt from roughly the Old Kingdom to the Late Period. The species epithet “semkhu” is the perfect passive singular participle, “the forgotten,” of “semekh,” the ancient Egyptian verb “to forget.” Collectively, “the forgotten lord of the oasis” alludes to both the relatively recent emergence of latest Cretaceous non-marine vertebrate fossils from continental Africa (particularly Egypt) and the lengthy and complicated history of the holotypic specimen (see above). Eric Gorscak, Matthew C. Lamanna, Daniela Schwarz, Verónica Díez Díaz, Belal S. Salem, Hesham M. Sallam and Marc Filip Wiechmann. 2023. A New titanosaurian (Dinosauria: Sauropoda) from the Upper Cretaceous (Campanian) Quseir Formation of the Kharga Oasis, Egypt. Journal of Vertebrate Paleontology. e2199810. DOI: 10.1080/02724634.2023.2199810 |
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