5 research outputs found
A skull of the extinct tayassuid Brasiliochoerus stenocephalus (Lund in Reinhardt, 1880) (Mammalia, Cetartiodactyla) from the Late Pleistocene of southern Brazil: morphology and taxonomy
Among the several fossils of South American tayassuids, it is remarkable the presence of a well-preserved skull from southern Brazil (Chuí Creek, Santa Vitória do Palmar, Santa Vitória Formation). Here, we provide an update in the taxonomic arrangement and anatomical description of this specimen assigned to Brasiliochoerus stenocephalus based on the combination of the following traits: 1) long rostrum with a markedly convex profile; 2) anterior margin of the orbits located behind the vertical plane of the distal part of M3; 3) facial crests of the zygomatic arch forming an angle of about 80° relative to the molar series; 4) postorbital process more developed and ventrally projected in comparison to other tayassuids; 5) absence of a sagittal crest and presence of short parasagittal crests; 6) presence of curved temporal crests; 7) accentuated basicranial flexion; 8) bunodont and brachydont cheek teeth; 9) conspicuous pneumatization; 10) short postcanine diastema; and 11) cranium with no postorbital depression. This specimen was collected from sedimentary levels that contain a diverse assemblage of Pleistocene terrestrial mammals. Based on living analogous species, the presence of this taxon indicates dry and relatively open environments at some part of the Late Pleistocene in the study area.Fil: Copetti, Paula Lopes. Universidade Federal de Santa Maria; BrasilFil: Gasparini, Germán Mariano. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Departamento Científico de Paleontología de Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Pereira, Jamil Corrêa. Museu Coronel Tancredo Fernandes de Mello; BrasilFil: Fontoura, Emmanuelle. Universidade Federal de Santa Maria; BrasilFil: Lopes, Renato Pereira. Universidade Federal do Rio Grande do Sul; BrasilFil: Kerber, Leonardo. Universidade Federal de Santa Maria; Brasi
A new species of coral-feeding nudibranch (Mollusca: Gastropoda) from the Gulf of Thailand
The validity and position of the Indo Pacific genus Phestilla Bergh, 1874 (Fionoidea: Trinchesiidae) have been subject of some controversy as a result of several recent studies, which have sequentially synonymized or re-established it. At present, the genus includes eight valid species, the most of them described in the nineteenth and twentieth centuries, and all but one feeding on scleractinian corals of four genera: Porites Link, 1807 (Poritidae), Tubastraea Lesson, 1830, Dendrophyllia Blainville, 1830 (Dendrophylliidae) and Montipora Blainville, 1830 (Acroporidae). The discovery of an unknown Phestilla species feeding on Pavona explanulata (Lamarck, 1816) (Agariciidae) in Koh Tao, Thailand, motivates this work, in which this new species is described providing morphoanatomical and molecular characters. In addition, its systematic position and ecological significance as coral parasite are discussed