Middorsal Scales Research Articles

A new species of gracile blind snake in the genus Letheobia (Squamata: Scolecophidia: Typhlopidae) from Sagalla Hill, south-eastern Kenya

ABSTRACT The members of the typhlopid Letheobia pallida group are characterised by having a divided or split ocular scale. Letheobia wrayi sp. nov., differs from all other members of this group by having a low mid-dorsal scale count of 355 (other taxa 376–670). It also has a rostral which is rounded, not truncated posteriorly, and its nasal suture arises from the base of the first (not second) labial. In the new species the number of middorsal scales is similar to that of L. swahilica, but it is larger in total body length (245 mm compared to 190 mm). Letheobia wrayi sp. nov., differs from L. toritensis and L. pallida that have > 400 mid-dorsals. The new species can be distinguished from L. mbeerensis (mid-dorsals > 600, long tail 2.9% vs 1.2% short tail). It is known only from the holotype collected on the Sagalla Hill–Taita Hills at an elevation of about 1 100 m within a dry deciduous forest zone.

A new record and a novel morph description of Boigastoliczkae (Squamata, Colubridae) from China.

The Asian Cat Snake genus Boiga Fitzinger, 1826 includes 37 species, with high species diversity. Five species of Boiga have been recorded in China including B.multomaculata (Boie, 1827), B.kraepelini (Stejneger, 1902), B.cyanea (Duméril, Bibron & Duméril, 1854), B.guangxiensis (Wen, 1998) and B.siamensis (Nutaphand, 1971). Previously, the validity of the species Boigastoliczkae (Wall, 1909) was controversial. B.stoliczkae was considered in synonymy with B.ochracea. Currently, the taxonomy of B.multomaculata and B.ochracea (Theobald, 1868) was revised so that B.multomaculata and B.ochracea actually represent a single species and B.stoliczkae was recognised as a valid species. B.stoliczkae was previously known to be found in the west from central Nepal through Darjeeling, Sikkim and Bhutan to Arunachal Pradesh and Assam in north-eastern India. One adult female specimen of the Asian Cat Snake was collected from Gyirong County, near the China-Nepal border, Tibet, China during fieldwork on August 2023. We compared morphology and mitochondrial DNA sequence data with all the species of the genus Boiga. Both datasets strongly supported referring the Chinese specimens to B.stoliczkae (Wall, 1909) due to the 21 mid-dorsal scale rows and the uncorrected p-distance (mitochondrial DNA gene cytochrome b) between this specimen and B.stoliczkae which is 1.7%. We further described morphological characters of the Chinese specimen in detail and compared these with the specimens that had been previously described. The dorsal ground colour of the Chinese specimen is dark brown, with a black stripe distributed almost evenly across the tail. This is a novel morph of the species B.stoliczkae. The newly-collected Chinese specimen expands the distribution of the species on the Himalaya range.

A NEW DWARF GECKO SPECIES (SQUAMATA: GEKKONIDAE: Cnemaspis) FROM THE NORTHERN WESTERN GHATS OF INDIA

Based on molecular and morphological data, I describe a new species of the polyphyletic gekkonid genus Cnemaspis Strauch, 1887 from the northern Western Ghats in India. The new species is the second smallest known Indian dwarf gekkonid and belongs to the clade of C. girii[i] sensu Pal [i]et al. (2021). It is genetically distinct from all congeners of the C. girii clade by p-distance ranging from 3.8 to 8.4 % on the 16S rRNA gene. Morphologically, the new species can be distinguished from all congeners by having the following combination of characters: A small species with adult males reaching a maximum SVL 27.0 mm; heterogeneous dorsal pholidosis with 11–12 longitudinal rows of enlarged tubercles; males with 3–4 femoral pores on each thigh, separated medially by 19–24 poreless scales; 63–65 middorsal scales; 136–150 ventral scales; 33–35 midbody scales; 12–14 subdigital lamellae under fourth digit of pes; feebly carinate scales on the neck and chest; and absence of conical or spine-like tubercles on flank.

A new species of threadsnake in the genus Myriopholis (Squamata: Scolecophidia: Leptotyplophidae) from southeastern Kenya

ABSTRACT A new threadsnake species from the family Leptotyphlopidae, Myriopholis mackayi sp. nov., is described from the Tsavo area in southeastern Kenya. Myriopholis mackayi sp. nov. is a member of the Myriopholis longicauda group on the basis of having a low number of middorsal scales, a discrete frontal shield, a rounded snout, a small anterior supralabial, a moderate posterior supralabial, semilunar cloacal shield, and pinkish colouration in life (brown dorsum and tan venter after preservation). The species is known from a xeric habitat at moderate elevation. It is highly recommended that future phylogenetic work is done to establish its taxonomic relations to other leptotyphlopids.

“Anteaters” under the airport: a slender new species of blindsnake, genus Indotyphlops, from Timor-Leste (Scolecophidia: Typhlopidae: Asiatyphlopinae)

We describe a slender immature female blindsnake from the main airport in Dili, Timor-Leste, as a new species of Indotyphlops, adding a third species to the country's known blindsnake fauna of Sundatyphlops polygrammicus (Schlegel, 1839) and Virgotyphlops braminus (Daudin, 1803). The new species has the following combination of characteristics: small size (snout–vent length = 119 mm), slender body (relative body thickness 71), T-V supralabial imbrication pattern, relative rostral width 0.36, 434 middorsal scales, relative tail length 1.7%, absence of enlarged occipital scales, and apical spine absent. The snake was found in an ant nest under several flat rocks near the fuel depot of Nicolau Lobato International Airport, and this habitat and the discovery in a busy location with heavy human impacts indicate that the species is likely a primarily subterranean myrmeco- or termitophage.

A New Species of Pareas Wagler, 1830 (Squamata, Pareidae) from Northwestern Yunnan, China

A new species of Pareas Wagler, 1830 is described from Dulongjiang Township, Gongshan County, Yunnan Province, China. Phylogenetically, the new species is most closely related to Pareas kaduri Bhosale, Phansalkar, Sawant, Gowande, Patel and Mirza, 2020; however, the genetic divergence (uncorrected p-distance) of the cyt b gene between the new species and P. kaduri reached 9.4%. Morphologically, the new species can be distinguished from P. kaduri by the absence of preoculars, loreal bordering the orbit, the fusion of subocular and postocular, three rows enlarged vertebral scales, five rows keeled mid-dorsal scales at the middle of the body, having more subcaudals, and having a relatively longer tail. In addition, the new species can be distinguished from all other congeners by a combination of morphological characteristics. Our work brings the total number of recognized species of the genus Pareas to 29, of which 23 occur in China.

Resurrection of Pareas yunnanensis (Vogt, 1922) with description of a new species of Pareas from Yunnan Province, China (Squamata, Pareidae)

Based on molecular and morphological data of four specimens of Pareas Wagler, 1830 collected from the type locality of P. yunnanensis (Vogt, 1922), along with examination of the type specimens of P. yunnanensis, we revalidate this poorly known, secretive species. Furthermore, based on molecular and morphological lines of evidence we also describe a new species of Pareas from Xishuangbanna Prefecture, Yunnan Province, China. Morphologically, the new species closely resembles its sister species P. nigriceps Guo & Deng, 2009. However, the new species is divergent from the latter in cytochrome b mtDNA gene sequences, and can be distinguished from all congeners by the following combination of morphological characteristics: single preocular, postocular fused with subocular, loreal not bordering orbit, vertebral scales enlarged, 3–5 rows of mid-dorsal scales keeled at the middle of the body, ventral scales 160–171; subcaudals 62–64, dorsal surface of head solid black or reddish-brown, dark nuchal band present, iris brownish-black or reddish-brown.

A new species of snail-eating snakes of the genus Pareas Wagler, 1830 (Reptilia: Serpentes) from eastern Himalayas, India

A new species of snail-eating snakes of the genus Pareas Wagler, 1830 is described from the eastern Himalayas. The species Pareas kaduri sp. nov. differs from all known species of the genus in bearing the following suite of characters: SVL 455–550 mm, TaL/TL 0.184–0.207, brown dorsum with black transverse bands throughout the body, 15 dorsal scale rows throughout the body and mid-dorsal vertebral scale rows enlarged, 8 rows keeled in males, loreal not touching orbit, ventrals 160–183, subcaudals 65–70 in males, 52 in one female specimen, hemipenis short, unilobed and 6–7 maxillary teeth. Molecular data for mitochondrial 16S rRNA and cytochrome b genes further attest the distinctness of the new species, which was recovered as a member of the Pareas hamptoni clade. Our work brings the total number of species recognized within the genus Pareas to 20.

Description and Phylogeny of a New Species of Andean Lizard (Gymnophthalmidae: Cercosaurinae) from the Huancabamba Depression

We describe a new species of Macropholidus lizard from the Andean highlands of southern Ecuador and northern Peru based on recent collections. Among other characters, the new species differs from other species of Macropholidus in having a paired series of enlarged middorsal scale rows restricted to the nape, striated dorsal scales, as well as ocelli on tail, flanks, scapular region and neck. We also present a molecular phylogeny of Cercosaurinae and genetic distances as additional evidence supporting delimitation of the new species, which is sister to M. annectens from southern Ecuador. Data on Andean orogeny and age estimates of cercosaurine lizards suggest that the Huancabamba Depression, long recognized for its dual role as a biogeographic barrier and a migration corridor, has also served as a center of origin and diversification of Macropholidus lizards.

A century of waiting: description of a new Epictia Gray, 1845 (Serpentes: Leptotyphlopidae) based on specimens housed for more than 100 years in the collection of the Natural History Museum Vienna (NMW).

We describe a new species of Epictia based on eight specimens from Nicaragua collected and housed in the collection of the Natural History Museum Vienna for more than a century. The species differs from the congeners by the combination of external morphological characters: midtail scale rows 10; supralabials two, anterior one large and in broad contact with supraocular; infralabials four; subcaudals 14–19; middorsal scale rows 250–267; supraocular scales present; frontal scale distinct; striped dorsal color pattern with more or less triangular dark blotches on each scale; small white blotch in anterior part of dorsal surface of rostral present in five out of six specimens (two further specimens are lacking their heads); terminal spine and adjacent scales white. Eidonomic species separation from other Epictia spp. is also supported by a few qualitative and quantitative differences in vertebrae count and morphology. The new species is putatively assigned to the Epictia phenops species group based on external morphological characters and distribution.

A new blind snake of the genus Letheobia (Serpentes: Typhlopidae) from Rwanda with redescriptions of L. gracilis (Sternfeld, 1910) and L. graueri (Sternfeld, 1912) and the introduction of a non-invasive preparation procedure for scanning electron microscopy in zoology.

A new species of blind snake in the genus Letheobia is described from Akagera National Park in eastern Rwanda. The new species is most similar to species of the L. gracilis complex, particularly L. gracilis and L. graueri. It differs from all other species of the genus by a unique combination of morphological characters, including the highest number of middorsal scale rows (834) and the most extreme elongation (total-length/midbody-width ratio 131) of all species in the genus and of any species of snake in the world; 22-22-22 longitudinal scale rows; snout in dorsal profile rounded, in lateral profile bluntly rounded with an angular horizontal edge ventrally; rostral broad, posteriorly rounded; eyes invisible; supralabial imbrication pattern T-0; tail short (1.3 percent of total length) with an apical spine; and a pink life colouration. The holotype of the new species was collected in gallery forest at a lake shore surrounded by savanna at 1300 m elevation. We produced scanning electron microscope images of the heads of the investigated specimens applying a liquid-substitution preparation procedure which does not require coating or drying and thus does not irreversibly damage the investigated samples. The obtained images allow an easy and more accurate examination of the scalation.

New Species of Blindsnakes (Squamata: Gerrhopilidae) from the offshore islands of Papua New Guinea

I describe four new species of blindsnake of the genus Gerrhopilus from islands off the southeastern tip of New Guinea and from New Ireland to the northeast. All have ventral keels on the rostral scale, and most have previously been assigned in their respective museum collections to the species G. depressiceps. Examination of available specimens shows G. depressiceps to be a composite of species, and I emend the diagnosis of that species based on the holotype and one additional specimen from northeastern New Guinea. The species described as new here differ from G. depressiceps and from each other in a series of features, including shape of the snout, shape of the rostral scale, numbers of mid-dorsal scale rows, reduction patterns in longitudinal scale rows, body mass, degree of eye development, and color pattern. The new species all inhabit islands remote from the known range of G. depressiceps on New Guinea and have likely been separated from that species for millions of years.

Two new endemic species of Epictia Gray, 1845 (Serpentes: Leptotyphlopidae) from Northern Peru.

Herein, we describe two new thread snake species of the genus Epictia from elevations higher than 2000 meters above sea level in the Andes of the Cajamarca Region in Northern Peru. Both species share 10 midtail scale rows, a broad contact between the anterior supralabial and the supraocular scales in most of the specimens, and a yellow spot on the snout and the terminal part of the tail. Epictia venegasi sp. nov. is described on the basis of nine specimens and can further be differentiated from its congeners by having 211-221 mid-dorsal scale rows and a color pattern where each body scale is black on the anterior half and yellow on the posterior half. The description of Epictia vonmayi sp. nov. is based on two specimens which can further be differentiated from their congeners by having 196-205 mid-dorsal scale rows and 14 distinct black longitudinal stripes around the body, which run through the center of each scale and are separated by bright yellow interspaces; accordingly the tail exhibits 10 black longitudinal stripes which likewise run through the center of each scale.

A new species of Letheobia (Serpentes: Typhlopidae) from central Kenya.

A new species of blind snake in the genus Letheobia (L. mbeerensis sp. nov.) is described from the Mbeere area on the extreme lower slopes of southeastern Mt. Kenya. It is an attenuate blind snake, superficially similar to Letheobia lumbriciformis but with 20 midbody scale rows and 670 middorsal scales. It has a total length of 280 mm with the proportionally longest tail in the genus (2.9% of total length), a broad rostral, eyes barely visible and in life it is pink in color. The new species is known from only a single specimen collected at Siakago, in Mbeere-Embu, which lies at an elevation of about 1200m. It is a burrowing species and like many other blind snakes it is likely to be nocturnal and rarely encountered on the soil surface. The new species is incorporated into a key to the scolecophidian snakes of Kenya.

Osteology and Cartilaginous Elements of Trilepida salgueiroi (Amaral, 1954) (Scolecophidia: Leptotyphlopidae).

Morphological and anatomical studies on the Leptotyphlopidae have increased in the past 10 years, providing important data on the systematics of this group, mainly focused on the skull and lower jaw morphology. However, most studies are based on a single specimen, rarely combining more than one single method of assessing morphological information. Therefore, several data on postcranial morphology, sexual dimorphism, and ontogenetic and intraspecific variation of leptotyphlopids remain poorly understood. Herein, we provide a detailed description of the cranial and postcranial skeleton of Trilepida salgueiroi based on more than 20 specimens (including males, females and juveniles), as well as a description of osteology and cartilaginous elements through the use of combined methodologies such as X-ray scanning, high resolution CT-scanning, and clearing and staining of articulated and disarticulated specimens. We also provide data on the presence/absence of dimorphic and intraspecific variation of the observed characters. The presence of a statolithic mass in the cavum vestibuli differs from the pattern found in other scolecophidians. A correlation of dorsal vertebrae with ventral and subcaudal scales was found (1:1), as well as total number of vertebrae with middorsal scales (1:1), thoracolumbar vertebrae and ventral scales (1:1), and a higher number of caudal vertebra with subcaudal scales (1.23:1). Intraspecific variation was found in several elements of the skull, lower jaw, pelvic girdle and vertebral number, but no evidence of sexual dimorphism was found in any of the species characters analysed. The homologies of several elements are discussed, although still remaining poorly understood and unknown.

Key to the Ophiodes (Squamata: Sauria: Diploglossidae) of Paraguay with the description of a new species.

Ophiodes is a South American genus of legless diploglossid lizards. Four species have been formally described: O. intermedius, O. vertebralis, O. striatus, and O. fragilis; three additional species were described but not officially named in an unpublished dissertation. These species are referred to as Ophiodes sp. "1", Ophiodes sp. "2", and Ophiodes sp. "3". We recognize five species of Ophiodes in Paraguay, one widespread (O. intermedius) and four known from only one or two localities (O. fragilis, O. striatus, O. sp. "3", and an undescribed species, described herein). The new species described represents the fifth Paraguayan species and the eighth member of the genus. It is distinguished by a combination of the following characters: a high number of middorsal scales between occipital and cloacal opening (>165), 29 scale rows around midbody, the posterior limbs 4 scales long, and vertical black bars on the face absent.

Three new endemic species of Epictia Gray, 1845 (Serpentes: Leptotyphlopidae) from the dry forest of northwestern Peru.

Three new blind snake species of the genus Epictia are described based on material collected in the Peruvian Regions Amazonas, Cajamarca and La Libertad. All three species are well differentiated from all congeners based on characteristics of their morphology and coloration. They share 10 scale rows around the middle of the tail and possess two supralabials with the anterior one in broad contact with the supraocular. Epictia septemlineata sp. nov. has 16 subcaudal scales, 257 mid-dorsal scale rows, a yellowish-white rostral, and a black terminal spine. Epictia vanwallachi sp. nov. exhibits 16 subcaudals, 188 mid-dorsal scale rows, a grayish-brown rostral, and a yellow terminal spine. Epictia antoniogarciai sp. nov. features 14-18 subcaudals, 195-208 mid-dorsal scale rows, a bright yellow or yellowish-white rostral, and the terminal spine and terminal portion of the tail yellow. All three species were collected in the interandean dry forest valleys of the Marañón River and its tributaries. This region is an area of endemism and warrants further attention from systematic and conservation biologists.

A new species of Amerotyphlops from Northeastern Brazil, with comments on distribution of related species.

We describe a new species of Amerotyphlops from an upland forest enclave in the state of Paraíba, Northeastern Brazil. The new species is distinguished from the other seven South American species of Amerotyphlops by the combination of the following characters: nasal suture incomplete; rostral scale oval and yellowish cream with some dark brown spots; four supralabial scales; three infralabial scales; rows of scales around the body 18/18/18; middorsal scales from 204 to 225; dorsum with twelve to thirteen rows of scales dark brown and belly with four to five rows of scales immaculate yellowish cream; caudal spine dark brown; subcaudal scales 8-10 in female and 11-13 in males; maximum total length 233 mm. The new species is morphologically similar to A. amoipira and A. paucisquamus, sharing 18/18/18 rows of scales around the body and a small overlap of counts of middorsal scales.

A new blind snake (Typhlopidae) from northeastern Cuba.

Typhlops leptolepis sp. nov. is a new blind snake from Holguín Province, northeastern region of Cuba. The new species is characterized by its small and thin body size, as well as a narrow rostral in dorsal view, longer than broad, with parallel to curved sides, tapering toward anterior tip. The preocular is in contact with third supralabial only. It has 20 anterior scale rows reducing to 18 posteriorly at around midbody or posterior to midbody, moderate to high middorsal scale counts (250-308), and a peculiar coloration (head, neck, and tail whitish spotted in ventral view). Based on its morphology, the new species can be placed within the Typhlops lumbricalis species group and a key to the species belonging to this group is presented.

Recognizing Dangerous Snakes in the United States and Canada: A Novel 3-Step Identification Method

The rapid and accurate recognition of dangerously venomous snakes following bites is crucial to making appropriate decisions regarding first aid, evacuation, and treatment. Past recommendations for identification of dangerous North American pit vipers have often required subjective determinations of head shape or relied on traits shared with some nondangerous species (elliptical pupils and undivided subcaudal scales). Heat-sensitive facial pits are diagnostic but require close examination of the dangerous head, and cephalic traits are useless when working with a decapitated carcass. Exclusive of cephalic traits, pit vipers north of Mexico can be recognized by the combination of keeled middorsal scales and undivided subcaudal scales. The order of colored rings is usually suggested to identify coral snakes in the United States, yet extension of the colored rings across the ventral scales must be added as an essential identifying factor to ensure elimination of all harmless look-alikes. A novel 3-step flow chart is presented that allows dangerous snakes in the United States and Canada to be recognized quickly and dependably without relying on cephalic traits. This process cannot be used in other countries, however, due to greater variability of these characteristics in snakes from other parts of the world. Finally, close examination of potentially venomous snakes is extraordinarily dangerous and steps to safeguard those making such observations are discussed.