[Herpetology • 2014] A Checklist and Key to the Homalopsid Snakes (Reptilia, Squamata, Serpentes), with the Description of New Genera

TABLE 2. Homalopsid species are grouped based on morphological and molecular work.
 The Fangless Indonesian Group was recently recognized and placed within the Homalopsidae by Murphy et al. (2011). (Photo A Brachyorrhos raffrayi by J.C.M.) Alfaro et al. (2008) recognized four clades. Their clade A corresponds with our Plumbea Group, containing a highly aquatic undescribed species from Lake Towuti, Sulawesi. (Photo B Hypsiscopus plumbea by Daryl R. Karns.) The South China Group is linked by similar morphology, and was long considered to be part of Enhydris. Kumar et al. (2012) found Myrrophis chinensis to be the sister to the southwest Indian Dieurostus dussumierii (also previously considered part of Enhydris). (Photo C Myrrophis chinensis by Steve Mackessy.) The two species in the Fossorial-Aquatic Group share similar morphology and geography but remain unconfirmed by molecular studies. (Image D Miralia alternans from Jan & Sordelli, 1860–1881.) Similarly, most members of the South Asian Group have not been included in molecular studies. The group shares some morphology and geography. (Photo E Dieurostus dussumierii by Biju Kumar.) The Pahang Mud Snake, Kualatahan pahangensis, is of uncertain relationship. It may be allied with the South Asian Group or the Enhydris Group. The Enhydris Group is centered in Indochina, they use freshwater habitats, and group membership of all but Enhydris chanardi has been supported with molecular and morphological data (Alfaro et al., 2008; Karns et al., 2010a). (Photo F Enhydris enhydris by J.C.M.) The Punctata Group is centered on the Sunda Shelf and shares similar morphology. Only Phytolopsis punctata has been included in molecular studies. (Photo G Homalophis doriae by Daryl R. Karns.) The Saltwater Group has been well documented with molecular data (Alfaro et al., 2008). (Photo H Cantoria violacea by J.C.M.) The Australasian Group is well supported by a close genetic relationship between Pseudoferania and Myron (Alfaro et al., 2008; Kumar et al., 2012; Pyron et al., 2013) and shared morphology and geography with the other members of the group. (Photo I Pseudoferania polylepis by J.C.M.) The Sunda Group is at best tentative, Alfaro et al. (2008) found a sister relationship between Erpeton and Subsessor bocourti, while Murphy et al. (2011) found Erpeton to be the sister to Bitia, and Subsessor to be the sister to the Homalopsis and Cerberus groups; and Kumar et al. recovered Subsessor as the sister to Homalopsis. (Photo J Subsessor bocourti by J.C.M.) The Homalopsis Group is linked by similar morphology. (Photo K Homalopsis mereljcoxi by J.C.M.) The Cerberus Group has three of the five species linked with molecular data (Alfaro et al., 2004) and is strongly supported by Alfaro et al. (2008). (Photo L Cerberus dunsoni by J.C.M.)

squamates.blogspot.com | doi: 10.3158/2158-5520-14.8.1

Abstract

The colubroid snake family Homalopsidae contained 10 genera and 34 species of rear-fanged semi-aquatic and aquatic snakes in 1970 with the publication of Gyi's monograph. In 2007 Murphy had updated Gyi's work and the family held the same 10 genera with 37 species plus two genera with uncertain status (Anoplohydrus, Brachyorrhos). Molecular studies published in the first decade of the 21st century demonstrated that while the Homalopsidae is monophyletic, the species-rich genus Enhydris is polyphyletic. Molecular analysis also found Brachyorrhos to be the most basal member of the clade, confirming an earlier hypothesis that it was a fangless homalopsid. Subsequently, two other fangless genera of homalopsids were discovered. We revalidate the genera: Homalophis Peters, Hypsiscopus Fitzinger, Miralia Reuss, Phytolopsis Gray, and Raclitia Gray. Also, we describe five new genera for species lacking available names: Gyiophis, Kualatahan, Mintonophis, Sumatranus, and Subsessor. The new arrangement for homalopsid names resolves the problem of the formerly polyphyletic genus Enhydris. For all species, we provide a synonymy, information on types and type localities, a diagnosis, as well as remarks on taxonomic and nomenclatural problems and a dichotomous key. Recent evidence suggests homalopsids show high levels of endemism and cryptic speciation.

Keywords: aquatic snakes, mud snakes, Homalopsidae, terrestrial–aquatic transition, geographic distribution, taxonomy

Cover: Enhydris jagorii Peters from the Bung Ka Lo wetland in Thailand’s Central Plain. This is the only confirmed extant population of this snake. Enhydris jagorii inhabits a marshy wetland with a shallow central lake bordered by rice paddy.
Photo by J.C.M.

John C. Murphy and Harold K. Voris. 2014. A Checklist and Key to the Homalopsid Snakes (Reptilia, Squamata, Serpentes), with the Description of New Genera. Fieldiana Life and Earth Sciences. 8 :1-43. doi: http://dx.doi.org/10.3158/2158-5520-14.8.1

academia.edu/3588999/2014._A_Checklist_and_Key_to_the_Homalopsid_Snakes_Reptilia_Squamata_Serpentes_with_the_Description_of_New_Genera._Murphy_and_Voris

[Herpetology • 2013] Treerunners, Cryptic Lizards of the Plica plica group (Squamata, Sauria, Tropiduridae) of northern South America

Abstract

The arboreal, Neotropical lizard Plica plica (Linnaeus, 1758) has been long considered a widespread species with a distribution east of the Andes. A preliminary examination of 101 specimens from about 28 locations mostly north of the Amazon suggests that Plica plica is a cryptic species complex with taxa that can be distinguished on the basis of the number of scale rows at mid-body; the arrangement, shape and ornamentation of scales on the snout; the number of lamellae on the fourth toe; the number of subocular plates; as well as other commonly used external morphological traits. The allopatric species discussed here are concordant with northern South American geography. Plica plica (Linnaeus, 1758) is associated with the Guiana Shield (Suriname, Guyana and Venezuela). A second species, P. caribeana sp. n. is associated with the Caribbean Coastal Range of Venezuela including Trinidad and Tobago. A third, distinctive species, P. rayi sp. n. is associated with the middle Orinoco at the eastern edge of the Guiana Shield. Two other species, P. kathleenae sp. n. and P. medemi sp. n., each based upon a single specimen, one from the Sierra Acarai Mountains of Guyana, and the other from southern Meta, Colombia are described. In addition to morphological analyses, we sequenced 12S and 16S rDNA gene fragments from one Plica plica from Trinidad to assess its relationship and taxonomy to other mainland Plica cf. plica. The results suggest Plica caribeana sp. n. likely diverged prior to the separation of Trinidad from northern Venezuela. Isolation in the Caribbean Coastal Range during its rapid uplift in the late Miocene, combined with a marine incursion into northern Venezuela may have contributed to their genetic divergence from other populations.

Keywords: Arboreal lizards, Iguania, Neotropics, new species, systematics

Plica caribeana sp. n. Caribbean Treerunner

Hypsibatus agamoides – Court 1858: 440.

Uraniscodon plica – Boulenger 1885, 2: 180 [in part].

Plica plica – Burt and Burt 1931: 282 [in part].

Tropidurus plica – Frost 1992: 1 [in part].

Etymology: Named for its Caribbean Coastal Range distribution.

Distribution: Eastern Coastal Range (Cordillera de la Costa Oriental) of Venezuela south into Bolivar; Trinidad, the Bocas Islands (Huevos, Monos, and Gaspar Grande); Tobago (Murphy and Downie 2012).

Plica kathleenae sp. n. 
Kathleen’s Treerunner

Etymology: Named in honor of Kathleen Kelly, Division of Amphibians and Reptiles, Field Museum of Natural History, for her interest and effort on behalf of herpetology.
Distribution: Known only from the type locality in the Acarai Mountains of Guyana.


Plica medemi sp. n. 
Medem’s Treerunner

Etymology: The lizard is named in honor of Colombian herpetologist Fredrico Medem.
Distribution: Known only from the type locality at Angostura No. 2, Cerro de las Pinturas, Lower Guayabero, and Meta, Colombia.

Plica rayi sp. n. Ray’s Treerunner

Plica plica – Etheridge 1970: 242 (in part).

Etymology: This lizard is namedin honor of Ray Pawley, former Curator of Reptiles at Brookfield Zoo, for his lifelong interests and work on amphibians and reptiles. Suggested common name: Ray’s Treerunner.

Distribution: Known from two localities along the Orinoco River:Puerto Ayacucho, Amazonas, Venezuela and Puerto Carreno, Vichada, Colombia. The distance between these two locations is about 65 km. They have also been observed at Tobogan de la Selva and Raudal de Danto at Autana.

Figure 6. Distributions of Plica plica Group species discussed in this paper.
Yellow – Plica plica; white Plica caribeana (because of scale not all Trinidad localities were plotted); red – Plica kathleenae; green – Plica medemi; light blue – Plica rayi; and the type localities of Plica pansticta and Plica lumaria are show in dark blue and orange respectively. A Google Earth map.

John C. Murphy and Michael J. Jowers. 2013. Treerunners, Cryptic Lizards of the Plica plica group (Squamata, Sauria, Tropiduridae) of northern South America. ZooKeys 355: 49–77. doi: 10.3897/zookeys.355.5868

[Herpetology • 2012] Differences among Populations of the Mekong Mud Snake Enhydris subtaeniata (Serpentes: Homalopsidae) in Indochina

 This study examines between-population variation of the Mekong Mud Snake,  Enhydris subtaeniata (Bourret, 1934) in Thailand, Cambodia, Laos, and Viet Nam, and relates the observed patterns to previously published patterns based on molecular data.  Enhydris subtaeniata were collected from six representative locations throughout its range that encompassed three important river drainage basins: the Chao Phraya, the Middle Mekong and the Lower Mekong.  Data on size, sexual size dimorphism, scalation,
reproductive biology and diet were used to explore biogeographical patterns revealed by a previously published phylogenetic and population genetic analysis. In several cases the size and reproductive characteristics mirrored the genetic differences and habitat differences associated with the sampled locations.

Keywords: Freshwater snake, biogeography, sea levels, Mekong River, Chao Phraya River, Khorat Basin


2012. Differences among Populations of the Mekong Mud Snake (Enhydris subtaeniata: Serpentes: Homalopsidae) in Indochina
http://www.biology.sc.chula.ac.th/TNH/TNH%2012_2/5-HAROLD%20K.pdf
http://www.biology.sc.chula.ac.th/TNH/vol12%20no2.html


Lukoschek, V., Osterhage, J. L., Karns, D. R., Murphy, J. C. and Voris, H. K. 2011, Phylogeography of the Mekong mud snake (Enhydris subtaeniata): the biogeographic importance of dynamic river drainages and fluctuating sea levels for semiaquatic taxa in Indochina. Ecology and Evolution. doi:

http://dx.doi.org/10.1002/ece3.29

Karns, D. R., Lukoschek, V., Osterhage, J., Murphy, J, C., and Voris, H. K. 2010 Phylogeny and biogeography of the Enhydris clade (Serpentes: Homalopsidae). Zootaxa, 2452. 18-30. http://www.mapress.com/zootaxa/2010/f/z02452p030f.pdf
http://herpnation.com/hn-blog/the-mekong-mud-snake

[Herpetology • 2007] Enhydris vorisi • A review of Enhydris maculosa (Blanford, 1879) and the description of a related species (Serpentes, Homalopsidae) from Ayeyarwady River Delta. Myanmar

photo: http://flic.kr/p/bsoESw

Enhydris vorisi

A homalopsid snake endemic to the Ayeyarwady River Delta.

Murphy, John C. 2007. A review of Enhydris maculosa (Blanford, 1879) and the description of a related species (Serpentes, Homalopsidae). Hamadryad 31 (2): 281-287

[Herpetology • 2005] Enhydris gyii | Kapuas Mud Snake • A new species of Enhydris (Colubridae: Homalopsinae) from the Kapuas River System, West Kalimantan, Indonesia

Kapuas Mud Snake

Enhydris gyii Murphy, Voris & Auliya, 2005

Abstract

A new species of homalopsine water snake of the genus Enhydris is described from Kalimantan, Indonesia on the basis of three specimens. It differs from its close relative Enhydris doriae (Peters, 187 1) in the number of scale rows at midbody, a higher number of lower labials and ventral scales, plate like temporal scales, and a distinctive color pattern.

Etymology: Named after the late Burmese herpetologist Ko Ko Gyi, Professor at Rangoon University, and the first zoologist to revise the entire subfamily Homalopsinae in the 20th century.

 Murphy, J.C.; H.K. Voris & Auliya, M. 2005. A new species of Enhydris (Serpentes: Colubridae: Homalopsinae) from the Kapuas River System, West Kalimantan, Indonesia. Raffels Bulletin of Zoology. 53 (2): 271-275 http://archive.fieldmuseum.org/research_collections/zoology/pdf/murphy_voris_auliya_2005.pdf

 ‘Chameleon' snake can turn white in minutes 

A new species of snake capable of rapidly changing colour has been discovered deep in the forests of Borneo. Two specimens of the Kapuas mud snake (Enhydris gyii) were discovered in the swampy forests of Indonesia's Betung Kerihun National Park.

The half-metre-long venomous snake is normally brown with an iridescent sheen, but can turn white. It is not yet known whether the snake can become other colours too, or what exactly causes the change.

http://www.newscientist.com/article/dn9417-chameleon-snake-can-turn-white-in-minutes.html

http://en.wikipedia.org/wiki/Kapuas_mud_snake

[Herpetology • 2005] งูสายรุ้งลาย | Enhydris chanardi | Chanard’s Mud Snake • A new Thai Enhydris (Colubridae: Homalopsinae)

งูสายรุ้งลาย | Chanard’s Mud Snake

Enhydris chanardi Murphy & Voris 2005

photo: http://mirrorwild.com/

Head scales of preserved Chanard's Mud Snake

(photo: John C. Murphy | http://bangkokherps.wordpress.com/)

Murphy, J.C., and H.K. Voris 2005. A new Thai Enhydris (Serpentes: Colubridae: Homalopsinae). Raffles Bulletin of Zooogy 53(1):143-147. http://rmbr.nus.edu.sg/rbz/biblio/53/53rbz143-147.pdf

[Herpetology • 2012] Homalopsis mereljcoxi • The Masked Water Snakes of the Genus Homalopsis Kuhl & van Hasselt, 1822 (Serpentes, Homalopsidae), with the Description of A New Species

Homalopsis mereljcoxi sp. nov. from the Khorat Basin, near Khon Kaen, Thailand (~16°01” N, 102°35’ E). Photograph by JCM. The high contrast, evenly spaced, pale colored bands outlined in black that extend across the dorsum help distinguish this species from H. buccata which often have more irregular bands with less contrast. 

Homalopsis mereljcoxi photo: Michael Cota

Abstract

Masked water snakes of the genus Homalopsis are abundant in the wetlands of Southeastern Asia. Currently, two species are recognized, the widespread H. buccata Linnaeus and the Mekong drainage endemic H. nigroventralis Deuve. On the basis of morphology we resurrect H. hardwickii Gray and H. semizonata Blyth and describe a new species from Indochina. We establish a neotype for Coluber buccatus Linnaeus and examine the status of other names associated with this species. Homalopsis species can be distinguished from each other on the basis of dorsal scale row counts, the scales in the ocular ring, and other head scale architecture. The new species, Homalopsis mereljcoxi, is distinguished from all others by its one postocular and one postsubocular scale, and a higher dorsal scale row count (40–47 scale rows at midbody) that are reduced to more than 30 scale rows at the body’s posterior. The new species is heavily exploited for the skin trade at Tonle Sap, Cambodia. Homalopsis likely contains other cryptic species that have evolved in the changing aquatic habitats of Southeast Asia. A key to the species of Homalopsis is provided.

Key words: Homalopsis buccata, cryptic species, Homalopsis hardwickii, Homalopsis mereljcoxi, Homalopsis nigroventralis, Homalopsis semizonata, Southeast Asia, systematics, taxonomy

FIGURE 7. A. Homalopsis buccata from East Kalimantan 

| B. Homalopsis mereljcoxi sp. nov. from the Khorat Basin, near Khon Kaen, Thailand 

| C. Homalopsis nigroventralis from an unknown locality in Thailand. 

| D. Homalopsis semizonata from Myanmar: Tanintharyi Division

Homalopsis mereljcoxi sp. nov.

Holotype. A female, FMNH 263756 from Thailand, Nakhon Ratchasima Province, Wang Nam Khieo, Udon Sap (subdistrict), Ban Badan Reservoir (14°31’04” N, 101°58’25” E); collected 16 June 2004 by Daryl R. Karns and John C. Murphy.

Etymology. This new species is named in in honor of Merel “Jack” Cox, for his years of dedication to the study of the snakes of Thailand.

Distribution. Homalopsis mereljcoxi is known from lowland localities in Thailand, Cambodia, and Vietnam. On the western edge of its known range it is found as far north as Bung Cho, Uttaradit Province, Phichai District (~12°N, 104°E), Thailand and as far south as Lake Songkhla (~7°N, 100°E), Thailand. In Vietnam it is found at least as far east as Can Tho Province (~10°N, 105°E) and as far south as Vinh Thuan District Town in Kien Giang Province (~9°N, 105°E). It is present in Cambodia’s Tonle Sap, and it most likely occurs throughout the lower elevations of the Chao Phraya and Mekong drainages. It is possible, but unclear, if this species inhabits Myanmar. Gyi (1970) reports Myanmar Homalopsis with 39–43 middorsal scale rows, Homalopsis semizonata Blyth, 1855 inhabits the area on both side of the Gulf of Martaban and the Ayeyarwady delta and it has 38-43 scale rows which overlap the range of scale rows for H. mereljcoxi.

Natural history. Many authors have discussed the natural history of this species (Saint Girons 1972; Brooks et al. 2007, 2010; Karns et al. 2005, 2010) under the name Homalopsis buccata. The morphology of this species agrees well with the Cambodia specimens described by Saint Girons (1972), however his data included ventral counts of 154–180, a range with some specimens below the lower end of the range observed in our sample. Cambodian specimens with ventral counts lower than 160 (unpublished data) likely belong to one or more cryptic species. 

In Thailand, the habitat used by Homalopsis mereljcoxi includes small reservoirs, ditches, ponds, streams, and shallow wetlands (Karns et al. 2005; 2010). Snakes were primarily obtained from fishers’ gill nets, one specimen was hand collected from a pond at night while it floated near the surface in an ambush posture. Saint Girons (1972) described similar habitats in Cambodia: streams, rivers, irrigation canals, marshes, reservoirs and the banks of lakes and rivers; he also reports it in shallow water at night and describes it resting in burrows or crevices in the bank during the day, noting that specimens move very little while on land. Individuals released into shallow water escaped without hesitation, but placed in a river with steep banks, the snakes immediately sought refuge along the shore.

Murphy, J.C. et al. 2012: The masked water snakes of the genus Homalopsis Kuhl & van Hasselt, 1822 (Squamata, Serpentes, Homalopsidae), with the description of a new species.
Zootaxa, 3208: 1–26.

http://mapress.com/zootaxa/2012/f/z03208p026f.pdf

[Herpetology • 2011] Djokoiskandarus new genus for Cantoria annulata • The nomenclature and systematics of some Australasian Homalopsid snakes (Squamata: Serpentes: Homalopsidae)

Banded mangrove snake, Djokoiskandarus annulatus 

(Cantoria annulata) http://www.markoshea.tv/blog/wildwest.html

Abstract

 The external morphology and systematics of Australasian homalopsid snakes are examined against the background of recent molecular work. Two new species (Myron karnsi and Myron resetari) in the genus Myron Gray 1849 are described using the external morphology commonly applied to snake species. Cantoria annulata Jong 1926 and Hypsirhina polylepis Fisher 1886 represent endemic Australasian genera; Cantoria annulata is assigned a new genus, and the genus Pseudoferania Ogilby 1891 is resurrected for Enhydris polylepis. The zoogeography of the Australasian homalopsid clade is discussed.

Key words:– homalopsids, Myron, Cantoria, Enhydris,  Heurnia, nomenclature, new genus, new species.

Djokoiskandarus, new genus

Type species. – Cantoria annulata Jong, 1926 by monotypy.

Etymology. – The genus is named in honour of Indonesian herpetologist Djoko Iskandar. Gender of genus is masculine.

Distribution. – Southern coast of New Guinea.

Morphological Diagnosis. – Dorsal scale rows 21 at mid body; internasal separates prefrontal and nasals scales; frontal’s contact with the internasal makes this species readily distinguishable from all other homalopsids, including Cantoria violacea which has 19 scale rows at mid body and the prefrontal scales in broad contact. A number of species of Enhydris have 21 scale rows at mid body, but all of them have the nasal scales in contact. D. annulatus also has keeled scales in the fi rst three dorsal scale rows just anterior to the vent. A male is 578 mm in total length with a 108 mm tail; four females were 277–548 mm in total length. See Murphy (2007) for a more exhaustive description. 

Djokoiskandarus annulatus, new combination

Type Locality. – Prins Hendrik-eiland (Yos Sudarso), New Guinea, Indonesia (about 7º56'S and 138º21'E).

Distribution. – Southern coastal New Guinea.

Murphy, John C. 2011. The nomenclature and systematics of some Australasian Homalopsid snakes (Squamata: Serpentes: Homalopsidae). The Raffles Bulletin of Zoology, 59(2):229-236.

http://rmbr.nus.edu.sg/rbz/biblio/592/59rbz229-236.pdf

http://squamates.blogspot.com/2011/12/old-new-species.html

[Herpetology • 2011] Myron karnsi & M. resetari • Two new dwarf homalopsid snakes (Homalopsidae) from eastern Indonesia and western Australia

Two new dwarf homalopsid snakes of the genus Myron described in 2011. A. Myron karnsi from the Aru Islands in eastern Indonesia. B. Myron resetari from Western Australia. Both species have been long confused with Myron richardsonii, a species from northern Australia.These are small (less than 400 mm), coastal species that probably hunt fish in marine environments. They are two of a small number of snakes, other than true sea snakes and file snakes, that have been able to adapt to saltwater. M. karnsi is known from a single specimen, M. resetari was known from two specimens when described, but other specimens have been found in the last few months. JCM

Abstract

 The external morphology and systematics of Australasian homalopsid snakes are examined against the background of recent molecular work. Two new species (Myron karnsi and Myron resetari) in the genus Myron Gray 1849 are described using the external morphology commonly applied to snake species. Cantoria annulata Jong 1926 and Hypsirhina polylepis Fisher 1886 represent endemic Australasian genera; Cantoria annulata is assigned a new genus, and the genus Pseudoferania Ogilby 1891 is resurrected for Enhydris polylepis. The zoogeography of the Australasian homalopsid clade is discussed.

Key words:– homalopsids, Myron, Cantoria, Enhydris,  Heurnia, nomenclature, new genus, new species.

Myron karnsi, new species

Holotype: SMF 19569. 

Type Locality: Indonesia Aru, Kobroor, Selrutti (about 5º46'S and 134º31'E).

1917 Myron richardsoni — Rooij, 2:192

Etymology. – This species is named in honour of Daryl R. Karns, Hanover College and the Division of Amphibians and Reptiles, Field Museum of Natural History for his contributions to herpetological research and work with homalopsid snakes.

Distribution. – Known only from the type locality.

Myron resetari, new species

Holotype: QM J52861. 

Type locality: Broome, Western Australia (about 17º58'S and 122º14'E).

1970 Myron richardsonii — Gyi, pages 172–174, Fig. 28.

Etymology. – The specifi c name is in honour of Alan Resetar of the Division of Amphibians and Reptiles, Field Museum of Natural History for his life long dedication to herpetology and his behind the scenes contributions to homalopsid snake research.

Distribution. – Known only from the type locality, Broome, Western Australia; but it may be more widespread. Given Myron’s use of mangroves and mudfl ats it seems likely this snake is from the Roebuck Bay area of the Dampier Peninsula.

Murphy, John C. 2011. The nomenclature and systematics of some Australasian Homalopsid snakes (Squamata: Serpentes: Homalopsidae). The Raffles Bulletin of Zoology, 59(2):229-236.

http://rmbr.nus.edu.sg/rbz/biblio/592/59rbz229-236.pdf

http://squamates.blogspot.com/2011/12/old-new-species.html

http://www.arod.com.au/arod/reptilia/Squamata/Colubridae/Myron

[Herpetology • 2008] งูลายสอลาวเหนือ | Paratapinophis praemaxillaris • Rediscovery from northern Thailand

FIGURE 1. A female Paratapinophis praemaxillaris (FMNH 271447)

collected from Nan Province, northern Thailand.

ชื่อไทย: งูลายสอลาวเหนือ

ชื่อสามัญ: Angel's Mountain Keelback

ชื่อวิทยาศาสตร์: Paratapinophis praemaxillaris Angel, 1929

ABSTRACT

Paratapinophis praemaxillaris was described by Angel (1929) on the basis of two neonate specimens from Xieng-Khouang in northern Laos. Pope later placed the genus in the synonymy of Opisthotropis Günther, 1872. We collected five adult specimens along the Nan River, in northern Thailand. Here we describe the adults of Angel’s Stream Snake, discuss the

monotypic genus, its distribution, habitat, and diet. Based upon morphology we remove Paratapinophis Angel, 1929 from the synomomy of Opisthotropis. An identification matrix is provided for identifying snakes in the genera Opsithotropis, Parahelicops, and Paratapinophis Bourret, 1934, all have been considered Opisthotropis at one time or another, and we comment on the status of Opisthotropis.

KEY WORDS: Paratapinophis, Opisthotropis, Thailand, China, Laos, stream snakes

FIGURE 4. The microhabitat at the collection included waterfalls (seepage areas),

a gravel and sand bar, and shallow water between the bank and the gravel bar.

FIGURE 2. The map notes the four localities for Paratapinophis praemaxillaris is known from four localities: (1929) the type locality in Xieng-Khouang, Laos; (1981) Doi Saket, Thailand; (1982) Jindong, Yunnan Province, China; and (2007) the Nan River location in Nan Province, Chaloemprakait District, Huia Gon Subdistrict, at the Wang Pian Waterfalls, Thailand.

Murphy, J.C., Chan-ard, T., Mekchai, S., Cota, M. & Voris, H.K. 2008. The Rediscovery of Angel’s Stream Snake, Paratapinophis praemxillaris Angel, 1929 (Reptilia: Serpentes: Natricidae). The Natural History Journal of Chulalongkorn University 8(2): 169-183

http://www2.biology.sc.chula.ac.th/web%20of%20NHJCU%20PDF/8-2/8.%20MURPHY%20169-183.pdf