[Most Recent Entries] [Calendar View]
Friday, March 8th, 2024
| Time | Event | ||||||
| 2:03a | [Paleontology • 2024] Diving Dinosaurs? Caveats on the Use of Bone Compactness and pFDA for inferring Lifestyle
Abstract The lifestyle of spinosaurid dinosaurs has been a topic of lively debate ever since the unveiling of important new skeletal parts for Spinosaurus aegyptiacus in 2014 and 2020. Disparate lifestyles for this taxon have been proposed in the literature; some have argued that it was semiaquatic to varying degrees, hunting fish from the margins of water bodies, or perhaps while wading or swimming on the surface; others suggest that it was a fully aquatic underwater pursuit predator. The various proposals are based on equally disparate lines of evidence. A recent study by Fabbri and coworkers [2022] sought to resolve this matter by applying the statistical method of phylogenetic flexible discriminant analysis to femur and rib bone diameters and a bone microanatomy metric called global bone compactness. From their statistical analyses of datasets based on a wide range of extant and extinct taxa, they concluded that two spinosaurid dinosaurs (S. aegyptiacus, Baryonyx walkeri) were fully submerged “subaqueous foragers,” whereas a third spinosaurid (Suchomimus tenerensis) remained a terrestrial predator. We performed a thorough reexamination of the datasets, analyses, and methodological assumptions on which those conclusions were based, which reveals substantial problems in each of these areas. In the datasets of exemplar taxa, we found unsupported categorization of taxon lifestyle, inconsistent inclusion and exclusion of taxa, and inappropriate choice of taxa and independent variables. We also explored the effects of uncontrolled sources of variation in estimates of bone compactness that arise from biological factors and measurement error. We found that the ability to draw quantitative conclusions is limited when taxa are represented by single data points with potentially large intrinsic variability. The results of our analysis of the statistical method show that it has low accuracy when applied to these datasets and that the data distributions do not meet fundamental assumptions of the method. These findings not only invalidate the conclusions of the particular analysis of Fabbri et al. but also have important implications for future quantitative uses of bone compactness and discriminant analysis in paleontology.    Nathan P. Myhrvold, Stephanie L. Baumgart, Daniel Vidal, Frank E. Fish, Donald M. Henderson, Evan T. Saitta and Paul C. Sereno. 2024. Diving Dinosaurs? Caveats on the Use of Bone Compactness and pFDA for inferring Lifestyle. PLoS ONE. 19(3): e0298957. DOI: 10.1371/journal.pone.0298957  | ||||||
| 2:04a | [Botany • 2024] Begonia auritialata & B. ruchengensis (Begoniaceae) • Two New Species from China
Abstract China has an exceptional diversity in Begonia, holding the second largest number of described species in this genus at the national level. Many new taxa need to be explored and described. This paper reports two new species, Begonia ruchengensis (B. sect. Reichenheimia) and B. auritalata (B. sect. Platycentrum), from Hunan province and Guizhou province, respectively. Besides the detailed morphology description, color illustrations, and line drawings, the diagnoses of these two species distinguished from their allied taxa are provided. Their conservation statuses are evaluated according to The Guidelines for Using the IUCN Red List Categories. Keyword: Begonia ruchengensis, Begonia auritalata, new taxa, taxonomy, Flora of China, morphology, conservation
Begonia ruchengensis D.K.Tian, sp. nov. (sect. Reichenheimia) 汝城秋海棠 Diagnosis: This new species is mostly similar to B. fimbristipula Hance in similar plant size, leaf shape, leaf hairs, and morphology of flowers and fruits, but differs mainly in its thickly unillamelate (vs. thinly bilamellate) placentae of the ovary, later (Jun.–Oct. vs. Apr.–Jun.) flowering time, and smaller flower size (5–11 × 5–10 mm vs. 8–15 × 8–12 mm outer tepals of staminate flower). Etymology: The epithet “ruchengensis” is derived from Rucheng, a county name of Hunan province, where the type of the new species is collected.  
Begonia auritalata D.K.Tian & H.J.Wei, sp. nov. (sect. Platycentrum) 耳翅秋海棠 Diagnosis: The new species is mostly similar to B. villifolia Irmsch. in hairy leaves, flowers and fruits, but is easily differentiated by its 3 (vs. 2) incomplete-locular ovary, concaved (vs. flat) abaxial wing, shorter (to 60 vs. to 100 cm) plant, usually multicolored (vs. pure green) leaf, early (Feb. to Mar. vs. May to Jul.) flowering time. It is also morphologically close to B. khaophanomensis Phutthai & M.Hughes (Phutthai and Hughes, 2016) native to Thailand in the same section, but differs mainly by the latter’s leaf lobed (vs. unlobed), and abaxial wing larger (4 cm vs. ca. 1 cm long), and wing shape (oblong or obliquely triangular vs. auricular). Etymology: The epithet “auritalata” is derived from its auricular and concave abaxial wing of fruit. Daike Tian, Hongjing Wei, Cunzhong Huang, Lei Wu, Zhilin Chen, Zhiyou Guo, Xiaojun Sun, Songwei Wang, Qingmei Gao and Xin Li. 2024. Two New Species of Begoniaceae from China mainland. Taiwania. 69(1); 89 - 98. DOI: 10.6165/tai.2024.69.89 | ||||||
| 8:01a | [Botany • 2022] Paraphlomis hsiwenii (Lamiaceae) • A New Species from the Limestone Area of Guangxi, China
Abstract The indumentum of nutlets is shown to be of phylogenetic importance in previous molecular phylogenetic studies of Paraphlomis, a genus of Lamiaceae with approximately 30 species distributed mainly in southern China and Southeast Asia. Nearly half the species of Paraphlomis are known from limestone areas. In this study, we described and illustrated a new species, P. hsiwenii, from the karst mountain forests in Guangxi Zhuang Autonomous Region, China. Our molecular phylogenetic analyses revealed that P. hsiwenii is recovered in a clade consisting of species with hairy nutlets. The new species is morphologically most similar to P. pagantha from the same clade, but they differ in the morphology of lamina bases, length of pedicels and calyces, as well as the morphology of upper corolla lips. Keywords: Ajugoides, karst, Matsumurella, nutlet, Paraphlomideae
Paraphlomis hsiwenii Y.P.Chen & Xiong Li, sp. nov. Type China, Guangxi, Jingxi City, Nanpo Town, Longting, Diding Natural Reserve, among shrubs in forests of limestone area, 23°3'29.55"N, 105°57'13.82"E, alt. 1181 m, 25 Jun 2022, J.F. Xiao & X.L. Ma XJF095 (holotype: !; isotypes: K!, KUN!, MO!, PE!). Diagnosis: Paraphlomis hsiwenii is morphologically most similar to P. pagantha, but differs in having laminas glabrous above (vs. sparsely strigose above), bases of laminas not decurrent (vs. decurrent), calyces ca. 6 mm long (vs. ca. 4 mm long) with teeth ca. 2 mm long (vs. ca. 1 mm long), and upper corolla lips emarginate at apex (vs. entire at apex). Ya-Ping Chen, Jin-Fei Xiao, Chun-Lei Xiang and Xiong Li. 2022. Paraphlomis hsiwenii (Lamiaceae), A New Species from the Limestone Area of Guangxi, China. PhytoKeys. 212: 85-96. DOI: 10.3897/phytokeys.212.91174 | ||||||
| 8:33a | [Botany • 2022] Paraphlomis jinggangshanensis (Lamiaceae) • A New Species from Jiangxi, China
Abstract Paraphlomis jinggangshanensis (Lamiaceae), a new species from Jiangxi Province, China, is described and illustrated. The new species is morphologically similar to P. intermedia, but can be easily distinguished from the latter by its cordate leaf base (vs. cuneate, decurrent), stem and calyx tube with glandular hairs (vs. short pubescent), and glabrous anthers (vs. ciliate anthers). A phylogenetic analysis, based on ITS regions, suggests that P. jinggangshanensis represents a separate branch in Paraphlomis and is closely related to Clade II. It is currently known only from Jinggangshan National Natural Reserve. Because of its limited distribution and small population size, the species was assessed as Near Threatened (NT) according to the IUCN Red List Categories and Criteria. Keywords: IUCN, Jinggangshan, Paraphlomideae, phylogenetic
Paraphlomis jinggangshanensis Boufford, W.B. Liao & W.Y. Zhao, sp. nov. 井冈山假糙苏 Diagnosis: Paraphlomis jinggangshanensis is morphologically similar to P. intermedia, but differs by its pubescence of glandular trichomes, cordate leaf base, many-branched stems and glabrous anthers. Etymology: The specific epithet “jinggangshanensis” is derived from the type locality, Jinggangshan National Natural Reserve, Jiangxi Province, China. Wan-Yi Zhao, Zhong Zhang, Qiang Fan, Chun-Quan Chen, Wen-Bo Liao and David E. Boufford. 2022. Paraphlomis jinggangshanensis (Lamiaceae), A New Species from Jiangxi, China. PhytoKeys. 204: 1-8. DOI: 10.3897/phytokeys.204.87654 | ||||||
| 8:49a | [Botany • 2020] Turnera macrosperma (Turneraceae: Passifloraceae s.l.) • A New Species from the Brazilian Cerrado
Abstract Turnera macrosperma, a new species from the Brazilian Cerrado, is described and illustrated. The new species belongs to the series Turnera and can be characterized by the white petals with dark blue/violet basal spot and large seeds with papillose aril. SEM images, distribution map, and comments on taxonomy and morphology are presented. Keywords: Malpighiales; Protected areas; gen. Turnera ser. Turnera; taxonomy
Turnera macrosperma L.Rocha & Arbo, sp. nov. Lamarck Rocha and Maria Mercedes Arbo. 2020. A New Species of Turnera (Turneraceae, Passifloraceae s. l.) from the Brazilian Cerrado. Systematic Botany. 45(4); 826-832. DOI: 10.1600/036364420X16033963649309 | ||||||
| 9:38a | [Mammalogy • 2024] Ctenomys uco • A New living Species of the Genus Ctenomys (Rodentia: Ctenomyidae) from central-western Argentina
Abstract The genus Ctenomys Blainville, 1826 includes 68 living species of small to medium-sized (100–1200 g) caviomorph rodents of subterranean habits. During the last decade, this genus has been the subject of numerous taxonomic studies, including the description of new species and the proposal of novel synonyms. Based on phylogenetic analysis of mitochondrial DNA sequences and qualitative and quantitative morphological traits, here we review the species boundaries of the tuco-tucos of the species group of C. mendocinus and describe a new species. The new species is morphologically distinct from other phylogenetically and geographically close species of Ctenomys (e.g., C. fochi, C. mendocinus), showing several differences in their craniodental traits (e.g., proportionally longer nasals and less globose tympanic bullae). The new species occurs in montane grasslands and shrublands of northwestern Mendoza (ca. 2710 m a.s.l.) and in lowlands (ca. 1000 m a.s.l.) of the Monte Desert ecoregion in an area highly impacted by accelerated processes associated with the wine industry. Keywords: Caviomorpha, Ctenomys fochi, Mendoza, Monte, Octodontoidea, Southern Andean steppe, tuco-tucos
Ctenomys uco sp. nov. Morphological diagnosis: A small-sized tuco-tuco of the C. mendocinus species group (TOTL, 215–263 mm; TAIL, 64–79 mm; HFL, 31–36 mm: EAR, 6–8 mm; Weight, 109–138 g); dorsum Drab to Dusky Drab, which turns lighter on flanks; venter Light Brownish Drab to Light Drab, with line separating from dorsum scarcely defined; a patch above nose and forehead, blackish. Skull moderately robust, with rostrum and nasals proportionally long and narrow; premaxillary-frontal suture evident anterior to the naso-frontal suture; interorbital region with posteriorly divergent outer margins. Zygomatic arches thin, slightly divergent backwards in dorsal view; dorsal profile of cranium with a marked ventral inflection in the parietal-occipital region; incisive foramina short and narrow, recessed in a common fossa of posteriorly divergent outer borders; interpremaxillary foramen small or nearly absent; sphenopalatine vacuities nearly tear-shaped; auditory bullae moderately inflated and nearly oval, with salient auditory tubes. Etymology: We named this species in reference to the region where the type locality lays, the Valle de Uco (Uco Valley), which includes the Tupungato, Tunuyán, and San Carlos Departments in Mendoza Province, central western Argentina; this valley is well known for its fine wines. Raquel Alvarado-Larios, Pablo Teta, Pablo Cuello, J. Pablo Jayat, Andrea P. Tarquino-Carbonell, Guillermo D’Elía, Paula Cornejo and Agustina A. Ojeda. 2024. A New living Species of the Genus Ctenomys (Rodentia: Ctenomyidae) from central-western Argentina. Vertebrate Zoology. 74: 193-207. DOI: 10.3897/vz.74.e115242 | ||||||
| 2:38p | [PaleoIchthyology• 2024] Cosmoselachus mehlingi • A New operculate symmoriiform chondrichthyan (Symmoriiformes: Falcatidae) from the Late Mississippian Fayetteville Shale (Arkansas, United States)
We describe a new genus of symmoriiform chondrichthyan from the Late Mississippian Fayetteville Shale of Arkansas, United States, and include this fossil in a phylogenetic analysis of chondrichthyans. This taxon possesses elongate cartilaginous rays extending from the gill arches, forming an operculate structure that covers at least two of the branchial arches farther posteriorly. Although presence of a ‘hyoid operculum’ has been postulated in at least two unrelated Paleozoic sharks (e.g., Triodus, Tristychius), subsequent investigations failed to corroborate those claims. The new fossil therefore provides the first evidence of an endoskeletal operculum formed by elongate, fused pharyngeal arch rays in a chondrichthyan. KEYWORDS: Chondrichthyes, Symmoriiformes, operculum, CT scanning, phylogeny, new genus, new species Class CHONDRICHTHYES Huxley, 1880 Order SYMMORIIFORMES Maisey, 2007 Family Falcatidae Zangerl, 1990 Genus Cosmoselachus n. gen. Cosmoselachus mehlingi Etymology: Cosmoselachus mehlingi n. gen., n. sp. is named in honor of American Museum of Natural History Senior Museum Specialist Carl Mehling, nickname “Cosm”, therefore “Cosm” -oselachus, in recognition of his contributions toward the acquisition and identification of numerous fossil chondrichthyans, as well as his indefatigable enthusiasm for all unusual vertebrates and many years of service to paleontology. Allison W. Bronson, Alan Pradel, John S. S. Denton and John G. Maisey. 2024. A New operculate symmoriiform chondrichthyan from the Late Mississippian Fayetteville Shale (Arkansas, United States). GEODIVERSITAS. 46(4); 101-117. |
| << Previous Day |
2024/03/08 [Calendar] |
Next Day >> |