A parthenogenetic Varanus.

Amphibia-Reptilia 26(4):507-514. DOI:10.1163/156853805774806296.

Abstract:

We report on a case of parthenogenesis in the varanid lizard Varanus panoptes. Parthenogenesis was observed in a female kept alone for three years. A clutch was deposited from which a single egg could be secured and incubated. Incubation was successful and a male specimen hatched. Obviously the newborn was produced without contribution of a father. After the unisexual reproduction, the mother was kept with males and bisexual reproduction was observed, too. We performed DNA Fingerprinting and showed that the parthenogen and its mother exhibit almost identical DNA patterns. The bisexually produced offspring has only a subset of bands in common with the mother and another subset in common with the father. Thus DNA Fingerprinting is in accordance with our observations and confims parthenogenesis.We compare our results with existing cytological models of parthenogenesis and point out the following: 1. The mode of parthenogenesis described here is facultative, as the mother was able to reproduce in the bisexual mode as well. 2. The parthenogen is male and hence not a clone of the mother. 3. Almost complete heredity of maternal Fingerprint markers. All these points considered our case seem to fit to no known model of parthenogenesis exactly. But an additional recombination could result homogamety (would explain the sex of the parthenogen) while expressing almost all maternal bands.

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Montag, 25 September 2023 15:40

RHODIN, A. G. J. (1994)

Chelid Turtles of the Australasian Archipelago: II. A New Species of Chelodina from Roti Island, Indonesia.

Breviora 498: 1-31. Museum of Comparative Zoology; US ISSN 0006-9698; Cambridge, Mass.

Abstract:

A new species of Chelodina (Testudines: Pleurodira: Chelidae) is described from Roti Island, west of Timor, East Nusa Tenggara Province, in the southeastern Indonesian Archipelago. The species is endemic to Roti, a small and relatively xeric island. It is most similar and most closely related to Chelodina pritchardi from Papua New Guinea and C. longicollis from Australia, less closely related to C. novaeguineae and C. reimanni from New Guinea.

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Tortoise (Reptilia, Testudinidae) radiations in Southern Africa from the Eocene to the present.

Zoologica Scripta 46(4): 389-400

Abstract:

Africa, inclusive of the West Indian Ocean islands, harbours 11 of the world's 16 extant testudinid genera. Fossil records indicate that testudinids originated in Asia and dispersed first to North America and Europe (Early Eocene) and later to Africa (Late Eocene). We used mitochondrial (1870 bp) and nuclear (1416 bp) DNA sequence data to assess whether molecular data support the late cladogenesis of Southern African testudinid lineages. Our results revealed strong support for the monophyly of a clade consisting of Kinixys, the two Malagasy genera and four Southern African genera (Psammobates, Stigmochelys, Homopus and Chersina). Kinixys diverged from this clade in the Late Palaeocene, suggesting that testudinids occupied Africa at an earlier date than indicated by fossil records. The Southern African tortoises consist of three, strongly supported clades: Psammobates + Stigmochelys; the five-toed Homopus + Chersina; and the four-toed Homopus. Due to the paraphyly of Homopus, we propose the taxonomic resurrection of Chersobius for the five-toed Homopus species (boulengeri, signatus and solus). Cladogenesis at the genus level occurred mainly in the Eocene, with Chersina and Chersobius diverging in the Oligocene. The latter divergence coincided with species-level radiations within Homopus (areolatus and femoralis) and Psammobates (oculifer, geometricus and tentorius). Our phylogeny could not resolve relationships within Psammobates, indicating rapid speciation between the Late Oligocene and Early Miocene. The Chersobius species were the last to diverge in the Early to Mid-Miocene. By the Mid-Miocene, P. tentorius started to differentiate into four lineages instead of the three recognized subspecies: P. t. tentorius, P. t. trimeni and two P. t. verroxii subclades occurring north and south of the Orange River, respectively. Terminal radiations in several taxa suggest the existence of cryptic species and a more diverse tortoise fauna than currently recognized. Factors contributing to this diversity may include the early origin of African testudinids and climatic fluctuations over a heterogeneous landscape.

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Samstag, 23 September 2023 15:22

SEIDEL, M.E. & ERNST, C. H. (1996)

Catalogue of American Amphibians and Reptiles: Pseudemys 625.1-7.

Published by the Society for the Study of Amphibians and Reptiles.

Volltext: https://repositories.lib.utexas.edu/bitstream/handle/2152/45310/0625_Pseudemys.pdf?sequence=1&isAllowed=y

The Catalogue (Print ISSN: 2325-4882; Online ISSN: 2325-5021) consists of accounts of taxa prepared by specialists, including synonymy, description, diagnosis, phylogenetic relationships, published descriptions, illustrations, distribution map, and comprehensive list of literature for each taxon. Over 900 accounts have been published since the initiation of the series in 1963. The series covers amphibians and reptiles of the entire Western Hemisphere. Previously, accounts were published as loose-leaf separates; beginning in 2013 accounts are published as on-line PDFs.


All accounts are open access and are available for free download at the University of Texas Library Repository.

seidel-biblio

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In praise of subgenera: taxonomic status of cobras of the genus Naja Laurenti (Serpentes: Elapidae).

ZOOTAXA 2236 (1): 26-36. 21 Sep. 2009.
DOI: https://doi.org/10.11646/zootaxa.2236.1.2

Abstract:

The genus Naja Laurenti, 1768, is partitioned into four subgenera. The typical form is restricted to 11 Asian species. The name Uraeus Wagler, 1830, is revived for a group of four non-spitting cobras inhabiting savannas and open formations of Africa and Arabia, while Boulengerina Dollo, 1886, is applied to four non-spitting African species of forest cobras, including terrestrial, aquatic and semi-fossorial forms. A new subgenus is erected for seven species of African spitting cobras. We recommend the subgenus rank as a way of maximising the phylogenetic information content of classifications while retaining nomenclatural stability.

wallach-biblio

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Parachute geckos free fall into synonymy: Gekko phylogeny, and a new subgeneric classification, inferred from thousands of ultraconserved elements.

Preprint: doi: https://doi.org/10.1101/717520
Molecular Phylogenetics and Evolution 146: 106731

Volltext (Preprint): https://www.biorxiv.org/content/10.1101/717520v1.full.pdf+html

Abstract:

Recent phylogenetic studies of gekkonid lizards have revealed unexpected, widespread paraphyly and polyphyly among genera, unclear generic boundaries, and a tendency towards the nesting of taxa exhibiting specialized, apomorphic morphologies within geographically widespread “generalist” clades. This is especially true in the Australasia, where the monophyly of Gekko proper has been questioned with respect to phenotypically ornate flap-legged geckos of the genus Luperosaurus, the Philippine false geckos of the genus Pseudogekko, and even the elaborately “derived” parachute geckos of the genus Ptychozoon.

Here we employ sequence capture targeting 5060 ultraconserved elements to infer phylogenomic relationships among 42 representative ingroup gekkonine lizard taxa. We analyzed multiple datasets of varying degrees of completeness (10, 50, 75, 95, and 100 percent complete with 4715, 4051, 3376, 2366, and 772 UCEs, respectively) using concatenated maximum likelihood and multispecies coalescent methods.

Our sampling scheme was designed to address four persistent systematic questions in this group:

(1) Are Luperosaurus and Ptychozoon monophyletic and are any of these named species truly nested within Gekko?

(2) Are prior phylogenetic estimates of Sulawesi’s L. iskandari as sister to Melanesian G. vittatus supported by our genome-scale dataset? (

3) Is the high elevation L. gulat of Palawan Island correctly placed within Gekko? (

4) And, finally, where do the enigmatic taxa P. rhacophorus and L. browni fall in a higher-level gekkonid phylogeny?

We resolve these issues; confirm with strong support some previously inferred findings (placement of Ptychozoon taxa within Gekko; the sister relationship between L. iskandari and G. vittatus); resolve the systematic position of unplaced taxa (L. gulat, and L. browni); and transfer L. iskandari, L. gulat, L. browni, and all members of the genus Ptychozoon to the genus Gekko. Our unexpected and novel systematic inference of the placement of Ptychozoon rhacophorus suggests that this species is not related to Ptychozoon or even Luperosaurus (as previously expected) but may, in fact, be most closely related to several Indochinese species of Gekko. With our final, well-supported topologies, we recognize seven newly defined subgenera to accommodate ∼60 species within the more broadly defined and maximally-inclusive Australasian genus Gekko. The newly defined subgenera will aide taxonomists and systematists in species descriptions by allowing them to only diagnose putatively new species from the most relevant members of the same subgenus, not necessarily the phenotypically variable genus Gekko as a whole, and we argue that it appropriately recognizes geographically circumscribed units (e.g., a new subgenus for a novel clade, entirely endemic to the Philippines) while simultaneously recognizing several of the most systematically controversial, phenotypically distinct, and phylogenetically unique lineages. An added benefit of recognizing the most inclusive definition of Gekko, containing multiple phylogenetically-defined subgenera, is that this practice has the potential to alleviate taxonomic vandalism, if widely adopted, by creating formally available, supraspecific taxa, accompanied by character-based diagnoses and properly assigned type species, such that future, more atomized classifications would necessarily be required to adopt today’s subgenera as tomorrow’s genera under the guidelines of The Code of Zoological Nomenclature. Not only does this simple practice effectively eliminate the nefarious motivation behind taxonomic vandalism, but it also ensures that supraspecific names are created only when accompanied by data, that they are coined with reference to a phylogenetic estimate, and that they explicitly involve appropriate specifiers in the form of type species and, ultimately, type specimens.

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Biological data on Holaspis guentheri laevis Werner, 1895 obtained from vivarium keeping.

Podarcis 2(3): 72-80.

Volltext: https://www.lacerta.de/AF/Bibliografie/BIB_4493.pdf

Summary:

Two types of vivaria are described for Holaspis guentheri laevis, one an approximation of the natural habitat and the other a more spartan design. In both the lizards do well, though we prefer the former design.

Courtship lasts 5-8 minutes and involves a flankbite and the male clasping the female with his hind legs. For oviposition the lizards must be provided with a humid substrate on which pieces of bark are deposited, preferably in a partly closed container, the substrate if possible being around 30°C. Oviposition of the clutch of two occurs at night. At oviposition eggs measure 6.8x12.0±0.8 mm and weigh 0.33 g. These eggs develop to 9.8x18.8 mm and 1.08 g. At 29°C incubation takes 55-57 days. Juveniles measure (HB+T) 22+33 mm and weigh 0.24 g, and resemble their parents, though less intensely coloured. In contrast to the adults' ventral colour the juveniles are ventrally pitch-black. At a head-body length of approx. 27 mm, the change into adult coloration begins, and is completed when the animal reaches 35 mm in length. Sexual maturity is reached after 1.5-2 years.

The proximal fusion of the third and fourth finger in Holaspis is hypothesised to dampen the impact after gliding flights.

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Preliminary Results of the Research on Biology, Ecology and Conservation of the Chelonoidis chilensis (Sensu Lato) Gray, 1870 Tortoise in Argentina.

Buenos Aires: Proyecto Tortugas, Fundación Vida Silvestre Argentina.
PDF, 45 Seiten, 8 Anhänge mit Grafiken.

waller-biblio

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Aesthetic aliens: invasion of the beauty rat snake, Elaphe taeniura Cope, 1861 in Belgium, Europe.

Bioinvasive Records 10(3). DOI:10.3391/bir.2021.10.3.24

Abstract:

We report on an established population of the beauty rat snake, Elaphe taeniura Cope, 1861, a large, oviparous colubrid native to Southeastern Asia, in Belgium. The snakes have invaded a railroad system next to a city in the northeast of the country. Our report is based on validated citizen science observations, supplemented with directed surveys. The species has been recorded in the wild since 2006, most probably following an introduction linked to the pet trade. Genetic identification, based on the COI gene, confirms that the sampled individuals belong to E. taeniura. In addition, the snakes recorded in Belgium phenotypically match E. t. taeniura, a Chinese subspecies. Exact date of introduction, invasion extent and population size are currently unknown, but the number of observations has increased in recent years. Sightings exist from an area of 208 km², yet the core distribution is estimated to be no more than 2 km². Based on what is currently known on its ecology and distribution, we estimate that the species represents medium environmental risk. However, the species' distribution and invasive potential in Belgium remain largely unknown. As management of more widely established snake populations is notoriously difficult, we advocate a rapid response as the most appropriate risk management strategy.

doorn-biblio

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Molecular Systematics and Phylogeny of Old and New World Ratnakes, Elaphe AUCT., and Related Genera (Reptilia, Squamata, Colubridae.

Russian J. Herpetology 9(2): 105-124.

Abstract:

The phylogenetic relationships of the Holarctic ratsnakes (Elaphe auct.) are inferred from portions of two
mitochondrial genes, 12S rRNA and COI. Elaphe Fitzinger is made up of ten Palaearctic species. Natrix
longissima Laurenti (type species) and four western Palaearctic species (hohenackeri, lineatus, persicus,
and situla) are assigned to Zamenis Wagler. Its phylogenetic affinities with closely related genera, Coronella and Oocatochus, remain unclear. The East Asian Coluber porphyraceus Cantor is referred to a new genus. This taxon and the western European Rhinechis scalaris have an isolated position among Old World ratsnakes. Another new genus is described for four Oriental species (cantoris, hodgsonii, moellendorffi, and taeniurus). New World ratsnakes and allied genera are monophyletic. Coluber flavirufus Cope is referred to Pseudelaphe Mertens and Rosenberg. Pantherophis Fitzinger is revalidated for Coluber guttatus L. (type species) and further Nearctic species (bairdi, obsoletus, and vulpinus). Senticolis triaspis is the sister taxon of New World ratsnakes including the genera Arizona, Bogertophis, Lampropeltis, Pituophis, and Rhinocheilus. The East Asian Coluber conspicillatus Boie and Coluber mandarinus Cantor form a monophyletic outgroup with respect to other Holarctic ratsnake genera and are referred to Euprepiophis Fitzinger. Three Old World species, viz. Elaphe (sensu lato) bella, E. (s.l.) frenata, and E. (s.l.) prasina remain unassigned. The various groups of ratsnakes (tribe Lampropeltini) show characteristic hemipenis features.

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