squamata

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WORK IN CURRENT HERPETOLOGY:

The Phylogenetic Position and Taxonomic Status of the Rainbow Tree Snake Gonyophis margaritatus (Peters, 1871) (Squamata: Colubridae)  [2014]

ABSTRACT:

Molecular phylogenies have provided strong evidence for clarifying the taxonomy of groups with ambiguous morphological traits, thus avoiding potentially misleading conclusions based on evolutionary convergence of these traits.

For snakes, established molecular databases along with new sequences from rare species allows us to estimate phylogenies, to clarify the phylogenetic relationships and test the monophyly of most taxonomic groups.

Using one mitochondrial gene and five nuclear loci, we evaluate the taxonomic status of a rare Southeast Asian serpent, the Rainbow Tree Snake Gonyophis margaritatus (Squamata: Colubridae) by inferring a molecular phylogeny of 101 snake species.

Both maximum likelihood and time- calibrated Bayesian inference phylogenies demonstrate that G. margaritatus is sister to Rhadinophis prasinus, previously considered to be part of a radiation of Old World ratsnakes. This group is in turn sister to a group containing Rhadinophis frenatus and Rhynchophis boulengeri with the entire clade originating in the mid-Miocene (~16 Ma) in Southeast Asia…

(read more: NovaTaxa - Species New to Science)

reference:

Chen, Xin, Alexander D. Mckelvy, L. L. Grismer, Masafumi Matsui, Kanto Nishikawa & Frank T. Burbrink. 2014. Zootaxa. 3881(6): 532–548. DOI: 10.11646/zootaxa.3881.6.3

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Sunbeam Snake (Xenopeltis unicolor)

is a species of non-venomous snake native to parts of Southeast Asia and Indonesia. They get the name sunbeam due to its highly iridescent scales that make it look like the snake is lighting up. The sunbeam snake is highly noted for its reproductive abilities and it its known to give birth of up to 10 eggs at a time. Due to the fact that they have no venom the snake relies on constriction to kill their prey. They spend most of their time below ground and prey on small mammals and other reptiles.

Phylogeny

Animalia-Chordata-Reptilia-Squamata-Serpentes-Xenopeltidae-Xenopeltis-unicolor

Image Sources: 1,2

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The Armadillo Lizard (Cordylus cataphractus) is a lizard endemic to desert areas of southern Africa. It is also known as the Typical Girdled Lizard, Armadillo Girdled Lizard, Golden Armadillo Lizard, and Armadillo Spiny-tailed Lizard.

The Armadillo Lizard possesses an uncommon antipredator adaptation, in which it takes its tail in its mouth and rolls into a ball when frightened. In this shape it is protected from predators by the thick, squarish scales along its back and the spines on its tail. This behavior, which resembles that of the mammalian armadillo, gives it its English common name. This behavior may have inspired tales of the mythical creature Ouroboros.

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Spider-tailed Horned Viper (Pseudocerastes urarachnoides)

…a species of Persian horned viper collected in western Iran in 2006. Like its common name suggests this unique viper has an odd wind scorpion shaped growth at the tip of its tail. Originally it was thought to be a Persian Horned Viper (Pseudocerastes persicus) with a odd tumor, but it was later reveled that a whole population had these growths and they were named a new species. 

The growth is actually used as a lure and experiments have shown that birds who peck at it were lead to the vipers head and eaten. So far it has only been observed preying on birds but it is though to prey on other predators of wind scorpions as well.

Phylogeny

Animalia-Chordata-Reptilia-Squamata-Serpentes-Viperidae-Viperinae-Pseudocerastes-P.urarachnoides

Images: Omid Mozaffari and Fathina et al.

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Armadillo Girdled Lizard, Ouroborus cataphractus©Trevor Hardaker

Clanwilliam, South Africa.

Ouroborus cataphractus [Syn. Cordylus cataphractus F. Boie, 1828] is a lizard endemic to desert areas of southern Africa.

Armadillo lizards are named for their appearance when in a defensive position. When threatened, they curl up, grip the tail in their jaws, and form a tight, armored ball, resembling an armadillo. Rows of spiny osteodermate scales covering the neck, body, tail, and limbs deter predators from seizing or swallowing these lizards. This position protects the soft underside of the lizard, which is its most vulnerable area.

Like other species of armadillo lizards, Ouroborus cataphractus has the ability to drop their own tail (autotomy) when in danger, and can grow it back slowly. But, unlike many other lizards, in this species the tail is a necessary part of its unique defensive position. Because of this, the lizard will not part with the tail easily or quickly and tail autotomy is used only as a last resort. That is why in many of the photographs of these lizards is common to appear biting its tail.

The Armadillo lizards have an unusual appearance and are rather easy to catch. They are captured and sold in the commercial pet trade to other countries, although collecting this species is illegal.

This species is classified as Vulnerable on the IUCN Red List.

Reptilia - Squamata - Cordylidae - OuroborusO. cataphractus

Source.

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Burton’s Legless Lizard (Lialis burtonis)

This no snake, this is actually a species of legless lizard or pygopodid native to Australia and New Guinea. Although they may look like snakes they have fleshy tongues opposed to snakes thin forked tongues, they also have ears. Other than their lack of appendages they are similar to other lizards and have a diet of other reptiles like geckoes and snakes.

Phylogeny

Animalia-Chordata-Reptilia-Squamata-Lacertilia-Pygopodidae-Lialis-burtonis

Image Source(s)

Kimberley Rock Monitor  (Glauert’s Monitor)

This long-necked monitor lizard is commonly known as the Kimberley Rock Monitor, and has the scientific name of Varanus glauerti (Varanidae).

Varanus glauerti is a medium-sized monitor (up to 80 cm in length) which occupies rocky habitats, being both terrestrial or arboreal. Males and pairs often share the same tree, and even the same branch stub, with no evidence of agonistic behavior outside the breeding season. They are active foragers.  

This species is distributed from western Kimberley in Western Australia, to the northwestern tip of the Northern Territory (Australia).

References: [1] - [2]

Photo: ©Henry Cook

Locality: Kimberley, Western Australia

Neotropical Rattlesnake - Crotalus durissus 

Crotalus durissus (Viperidae) is a neotropical species of rattlesnake with several subspecies along its range; all of them are venomous.

Other common names: Cascabel Rattlesnake, South American Rattlesnake, Yucatan Rattlesnake

References: [1]

Photo credit: ©Thierry Montford | Locality: French Guiana (2014)