Pairs Of Chin Shields Research Articles

A new species of Alopoglossus lizard (Squamata, Alopoglossidae) from the Southern Guiana Shield, northeastern Amazonia, with remarks on diagnostic characters to the genus.

I describe a new species of Alopoglossus from the Southern Guiana Shield in northern Brazilian Amazonia. The new species morphologically resembles A. angulatus in having scales on sides of neck similar in shape to dorsals, nongranular, keeled, and imbricate. Nonetheless, the presence of four pairs of chin shields, with the third pair heptagonal and separated from gulars by large scales, can distinguish the new species from A. angulatus. This description increases the species diversity of the genus Alopoglossus in eastern Amazonia, from where only one taxon was recognized to occur. In addition, I discuss the nomenclature of some diagnostic characters, on the chin region, to the genus, and I present an updated key to Alopoglossus.

A new species of Eremiascincus (Squamata: Sauria: Scincidae) from the Pilbara region of Western Australia

Lizards of the genus Eremiascincus Greer, 1979 include species from the Australian monsoonal tropics and the Lesser Sundas as well as a widespread radiation of banded forms from the Australian arid zone, some of which are ‘sand-swimmers.’ Here we describe a new, rusty red-coloured species of Eremiascincus from the Pilbara region of Western Australia. Unlike other Eremiascincus, E. rubiginosus sp. nov. is saxicolous and usually associated with deep gorges in the Hamersley Range. The new species differs morphologically from all other members of the genus by a combination of numerous mensural and scalation characters, including typically seven supralabials, three pairs of chin shields, a moderate-sized elliptical ear opening, smooth scales on dorsum and dorsal surface of tail lacking longitudinal ridges, scales on dorsal surface of fourth toe arranged in multiple rows with oblique sutures with only the terminal 1 – 4 single scales possessing transverse sutures, 24 – 31 subdigital lamellae under fourth toe that are grooved and bluntly callused, 10 – 13 plantar scales from heel to base of third toe and dark brownish-black calli on scales of palmar and plantar surfaces. Colouration and pattern are also unique in the genus, with a rich rusty red background colour on dorsum and tail, 17 – 24 narrow irregular bands on nape and dorsum that are at most a single scale wide and > 40 narrow bands on tail. The new species is the seventh Eremiascincus from Western Australia and also the sixth narrow-banded species in the genus.

Taxonomic review of the rare Mexican snake genus Chersodromus (Serpentes: Dipsadidae), with the description of two new species.

Chersodromus is an endemic Mexican genus of snakes characterized by fused prefrontals shield. Only two species were previously known within the genus, C. liebmanni and C. rubriventris. We describe two new congeners, one from the Sierra Madre Oriental of northern Puebla and another from the Atlantic lowlands of the Chimalapas region in southeastern Oaxaca. These new species can be clearly differentiated on the basis of their morphology. Diagnostic characters distinguishing congeners include the number of dorsal scale rows, supralabials, and infralabials contacting anterior chinshields; whether or not the mental contacts the first pair of chinshields; and the coloration of the belly. We provide hemipenal descriptions of three species for which males are known.

Description of Two New Species ofEutropis(Reptilia: Scincidae) from Sri Lanka with a Redescription ofEutropis madaraszi(Méhely)

Abstract I describe two new endemic Eutropis species, with restricted distributions from the Central Hills and Lowland wet zone of Sri Lanka. Both were previously identified as Eutropis macularia Blyth. Eutropis austini sp. nov. is a medium-sized skink immediately distinguished from E. macularia by coloration and in being larger, with only the upper pretemporal in contact with parietal, the first pair of chin shields in medial contact. Eutropis greeri sp. nov. is a medium-sized, spotted species that differs from E. macularia by coloration and is larger, with a heavily keeled dorsum and fragile skin. Eutropis greeri sp. nov. further differs from E. macularia in having only the upper pretemporal in contact with parietal and the first pair of chin shields in medial contact. Eutropis greeri sp. nov. is distinguished from E. austini sp. nov. in scalation, coloration, and having fragile skin. The identity of Eutropis madaraszi is stabilized through the designation of a neotype, and here is redescribed. Examinat...

A new species of <i>Dipsas</i> (Squamata: Colubridae) from Guyana

A new species of Dipsas is described from the Pakaraima Mountains of Guyana. The new species is characterised by 15 dorsal scale rows with the middorsal row slightly enlarged. four pairs of chinshields with the first pair elongate, elongate loreal entering orbit, one preocular, six upper labials, and head narrow anteriorly, increasing in width posteriorly. It could not be determined to which of Peters' (1960) species groups the new species belongs. The new species is known only from 1490 m elevation on Mount Ayanganna. a tepui in the Guiana Shield, where it was found in high-tepui low-canopy habitat, in bromeliads or branches. This is the first record of Dipsas as a member of the Guiana Shield high-tepui herpetofauna.

Description and Phylogenetic Relationships of a New Genus and Species of Lizard (Squamata, Gymnophthalmidae) from the Amazonian Rainforest of Northern Brazil

Marinussaurus curupira, a new genus and species of Gymnophthalmidae lizard is described from Iranduba, state of Amazonas, Brazil. The genus is characterized by an elongate body; short and stout pentadactyl limbs; all digits clawed; single frontonasal; two prefrontals; absence of frontoparietals; interparietal and parietals forming a straight posterior margin, with interparietal shorter than parietals; distinctive ear opening and eyelid; few temporals; three pairs of chin shields; nasal divided; a distinct collar; smooth, mainly hexagonal, dorsal scales; smooth quadrangular ventral scales; two precloacal and three femoral pores on each side in males; pores between three or four scales. Parsimony (PAR) and partitioned Bayesian (BA) phylogenetic analyses with morphological and molecular data recovered the new genus as a member of the Ecpleopodini radiation of the Cercosaurinae. A close relationship of the new genus with Arthrosaura is postulated.

Rediscovery and Revalidation of Takydromus sikkimensis (Günther, 1888) (Squamata: Lacertidae) from Sikkim, India

Abstract Takydromus sikkimensis was named in 1888 by A. Gunther on the basis of an 1872 description of grass lizards from Sikkim by F. Stoliczka. Subsequent workers have not considered this species valid and have even doubted the occurrence of Takydromus in Sikkim. We confirm the occurrence of grass lizards in the lower Teesta valley of Sikkim. These are consistent with the description of T. sikkimensis and are distinguishable from all other congeners on the basis of having 12 rows of enlarged ventral scales across midbody, three pairs of chin shields, 3–6 femoral pores on each thigh, and color pattern lacking stripes, spots, or ocelli. Because the type specimens are lost, and because there has been a persistent confusion regarding the identity, and even the existence, of the taxon described by A. Gunther as T. sikkimensis, we designate a neotype to stabilize the use of the revalidated name.

A new genus and species of eyelid-less and limb reduced gymnophthalmid lizard from northeastern Brazil (Squamata, Gymnophthalmidae)

Scriptosaura catimbau, a new genus and species of elongate, fossorial, sand swimming eyelid-less gymnophthalmid lizard is described on the basis of specimens obtained at Fazenda Porto Seguro, municipality of Buíque, State of Pernambuco, in the Caatingas of northeastern Brazil. The type locality is entirely included within the area of the recently created Parque Nacional do Catimbau. The new lizard lacks external forelimbs, has rudimentary styliform hindlimbs and is further characterized by the absence of prefrontal, frontal, frontoparietal and supraocular scales, and by having one pair of chin shields. A member of the Gymnophthalmini radiation, the new genus is considered to be sister to Calyptommatus from which it differs externally by the absence of an ocular scale and absence of an enlarged temporal scale.

A new species of coralsnake of the genus Calliophis (Squamata: Elapidae) from the Central Province of Sri Lanka

We describe a new species of coralsnake, Calliophis haematoetron, from central Sri Lanka. This is the second species of coralsnake known from the island country, after Calliophis melanurus. It differs from C. melanurus in coloration, possessing a relatively unpigmented head (vs. capped with black from rostrum to nuchal collar), no light spots posterolateral to the parietal plates (vs. one at each side), a banded body dorsum (vs. unicolored), a bright red body venter (vs. orange or yellow through most of the length), and red pigment lateral to the blue under-tail color (vs. no red on tail). It also differs from C. melanurus in aspects of lepidosis, in having a frontal that is shorter or equal in size (vs. longer) than the interparietal suture and a first sublabial that does not touch the second pair of chin-shields (vs. first sublabial broadly touching second pair of chin-shields). The new species is easily distinguished from all other Calliophis species in nearby India and Southeast Asia by characters of external morphology and coloration.

A new species of coralsnake of the genus Calliophis (Squamata: Elapidae) from the Central Province of Sri Lanka

We describe a new species of coralsnake, Calliophis haematoetron, from central Sri Lanka. This is the second species of coralsnake known from the island country, after Calliophis melanurus. It differs from C. melanurus in coloration, possessing a relatively unpigmented head (vs. capped with black from rostrum to nuchal collar), no light spots posterolateral to the parietal plates (vs. one at each side), a banded body dorsum (vs. unicolored), a bright red body venter (vs. orange or yellow through most of the length), and red pigment lateral to the blue under-tail color (vs. no red on tail). It also differs from C. melanurus in aspects of lepidosis, in having a frontal that is shorter or equal in size (vs. longer) than the interparietal suture and a first sublabial that does not touch the second pair of chin-shields (vs. first sublabial broadly touching second pair of chin-shields). The new species is easily distinguished from all other Calliophis species in nearby India and Southeast Asia by characters of external morphology and coloration.

The Specific Characters of the Celesti, with the Description of a New Species of Celestus (Sauria, Anguidae)

W HILE collecting and preserving several hundred specimens of seven species and subspecies of West Indian celesti, and handling and observing as many more during several years of field work, certain characters which are frequently listed as specific appeared to me to be of generic value. The specific characters which may be relied upon are: (1) arm length compared to distance from snout to ear; (2) number of undivided lamellae under longest toe; (3) scale count, mental to vent; (4) scale count around midbody; (5) number of pairs of chin shields; (6) character of keels and striae on dorsals; (7) position of angular subocular between upper labials; (8) average adult size; and (9) color pattern. Frequently one only of the above characters will suffice to classify a specimen. There are two groups of celesti, one having arms longer than the snout-toear distance, and the other, equal or shorter. This proportion is evident at any age (size) and immediately separates the long-armed C. duquesneyi, C. occiduus and C. o. hewardi from the short-armed C. maculatus, C. plei, C. crusculus crusculus, C. c. molesworthi and C. c. cundalli. The number of undivided subdigital lamellae under the longest toe is correlated with arm length, and is mentioned here for the sake of those who, in the past, have confused the short-arm-and-fewer-lamellae group with the young of the long-arm-and-more-lamellae group. Members of the long-arm group live in stone walls, cliffs, heaps of coconut husks or similar dry habitats and make their escape by running. Members of the short-arm group live beneath objects or among dead leaves and escape by wriggling. Their habitats do not necessarily overlap. All stages of growth of each group were found, but no intermediates between the two. The number of lamellae does not change with growth. The number of scales between the mental and the vent is a more accurate