37 research outputs found

    Gross morphology and microstructure of type locality ossicles of Psephophorus polygonus Meyer, 1847 (Testudines, Dermochelyidae)

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    Psephophorus polygonus Meyer, 1847, the first fossil leatherback turtle to be named, was described on the basis of shell ossicles from the middle Miocene (MN6-7/8?) of Slovakia. The whereabouts of this material is uncertain but a slab on display at the Naturhistorisches Museum Wien is considered the neotype. We rediscovered further type locality ossicles in four European institutions, re-evaluated their gross morphology and described for the first time their microstructure by comparing them with Dermochelys coriacea, the only living dermochelyid turtle. The gross morphology is congruent with that already described for P. polygonus, but with two significant exceptions: the ridged ossicles of P. polygonus may have a distinctly concave ventral surface as well as a tectiform shape in cross-section. They do not develop the external keel typical of many ossicles of D. coriacea. Both ridged and non-ridged ossicles of P. polygonus are characterized by compact diploe structures with an internal cortex consisting of a coarse fibrous meshwork, whereas the proportionately thinner ossicles of D. coriacea tend to lose the internal cortex, and thus their diploe, during ontogeny. The ossicles of both P. polygonus and D. coriacea differ from those of other lineages of amniotes whose carapace is composed of polygonal ossicles or platelets, in having growth centres situated at the plate centres just interior to the external bone surface and not within the cancellous core or closer to the internal compact layer. The new diagnosis of P. polygonus allows us to preliminarily re-evaluate the taxonomy of some of the Psephophorus-like species. Despite some macro- and micromorphological differences, it seems likely that Psephophorus was as cosmopolitan as extant Dermochelys and had a broadly similar ecology, with a possible difference concerning the dive dept

    ï»żA new subspecies of the Asiatic softshell turtle Amyda ornata (Gray, 1861) from its northern distribution range

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    We describe a new subspecies of Amyda ornata (Gray, 1861) from the southeastern parts of Bangladesh (Chittagong hill tracts), adjacent regions of north-eastern India (Mizoram, Assam and Tripura) and Myanmar, based on morphological characteristics. The holotype comprises some skeletal elements held by the Natural History Museum of Vienna; the five paratypes consist of living specimens in the private collection of PP “Turtle Island” (a turtle conservation zoo in Graz, Austria). After the genetic identity had been determined in a previous investigation, the morphological description was carried out by examining living specimens and photo documents; and additionally, by evaluating the computed tomography of further living animals with exact location data. Amyda ornata jongli ssp. nov. differs from the other Amyda ornata subspecies mainly by its relatively compact and stout head in subadults and adults, its paler, greyish and less contrasting colouration missing distinct bright yellow pigments, ochre-coloured irises, and the existence of more distinct tubercles in the neck region and in the posterior section of the carapace than both other subspecies of Amyda ornata. The tubercles along the front of the carapace protrude clearly in subadult and adult specimens. This softshell turtle is heavily exploited within its limited distribution. Therefore, special comments on conservation aspects are given together with a final discussion on distribution and systematics

    Where do you come from, stranger? A scientific-historical digression with discussion on nomenclature and taxonomy of Testudo graeca Linnaeus, 1758

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    It is shown that the location data for the terra typica restricta of Testudo graeca and for the terra typica designata for Testudo graeca are based on an incorrectly assigned location. In fact, the original place corresponds to Santa Cruz, known today as Agadir (Morocco) and not the old Spanish fortress of Santa Cruz near Oran in Algeria. Accordingly, populations of Testudo graeca from the Agadir environment have to be named Testudo graeca graeca instead of Testudo graeca soussensis. For the populations of Testudo graeca from the vicinity of Algiers, “mauritanica” is the next available name for this subspecies of graeca. Therefore, Testudo graeca mauritanica has to be used instead of Testudo graeca graeca. For Testudo graeca mauritanica, a lectotypus is designated

    ï»żA new subspecies of the Asiatic softshell turtle Amyda ornata (Gray, 1861) from its northern distribution range

    No full text
    We describe a new subspecies of Amyda ornata (Gray, 1861) from the southeastern parts of Bangladesh (Chittagong hill tracts), adjacent regions of north-eastern India (Mizoram, Assam and Tripura) and Myanmar, based on morphological characteristics. The holotype comprises some skeletal elements held by the Natural History Museum of Vienna; the five paratypes consist of living specimens in the private collection of PP “Turtle Island” (a turtle conservation zoo in Graz, Austria). After the genetic identity had been determined in a previous investigation, the morphological description was carried out by examining living specimens and photo documents; and additionally, by evaluating the computed tomography of further living animals with exact location data. Amyda ornata jongli ssp. nov. differs from the other Amyda ornata subspecies mainly by its relatively compact and stout head in subadults and adults, its paler, greyish and less contrasting colouration missing distinct bright yellow pigments, ochre-coloured irises, and the existence of more distinct tubercles in the neck region and in the posterior section of the carapace than both other subspecies of Amyda ornata. The tubercles along the front of the carapace protrude clearly in subadult and adult specimens. This softshell turtle is heavily exploited within its limited distribution. Therefore, special comments on conservation aspects are given together with a final discussion on distribution and systematics

    Where do you come from, stranger? A scientific-historical digression with discussion on nomenclature and taxonomy of Testudo graeca Linnaeus, 1758

    No full text
    It is shown that the location data for the terra typica restricta of Testudo graeca and for the terra typica designata for Testudo graeca are based on an incorrectly assigned location. In fact, the original place corresponds to Santa Cruz, known today as Agadir (Morocco) and not the old Spanish fortress of Santa Cruz near Oran in Algeria. Accordingly, populations of Testudo graeca from the Agadir environment have to be named Testudo graeca graeca instead of Testudo graeca soussensis. For the populations of Testudo graeca from the vicinity of Algiers, “mauritanica” is the next available name for this subspecies of graeca. Therefore, Testudo graeca mauritanica has to be used instead of Testudo graeca graeca. For Testudo graeca mauritanica, a lectotypus is designated

    Nomenclatural-taxonomic notes on the genus Ablepharus Fitzinger, 1824 (Squamata: Scincidae)

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    Gemel, Richard, Vergilov, Vladislav (2020): Nomenclatural-taxonomic notes on the genus Ablepharus Fitzinger, 1824 (Squamata: Scincidae). Zootaxa 4858 (3): 448-450, DOI: https://doi.org/10.11646/zootaxa.4858.3.1

    One extinct turtle species less: Pelusios seychellensis is not extinct, it never existed.

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    Pelusios seychellensis is thought to be a freshwater turtle species endemic to the island of Mahé, Seychelles. There are only three museum specimens from the late 19(th) century known. The species has been never found again, despite intensive searches on Mahé. Therefore, P. seychellensis has been declared as "Extinct" by the IUCN and is the sole putatively extinct freshwater turtle species. Using DNA sequences of three mitochondrial genes of the historical type specimen and phylogenetic analyses including all other species of the genus, we provide evidence that the description of P. seychellensis was erroneously based on a widely distributed West African species, P. castaneus. Consequently, we synonymize the two species and delete P. seychellensis from the list of extinct chelonian species and from the faunal list of the Seychelles
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