Wednesday, March 11, 2020

[Herpetology • 2020] Protobothrops kelomohy | งูเกอะลออมก๋อย • the Second Known Species of Lance-Headed Pit Viper (Squamata: Viperidae) from northern Thailand

Protobothrops kelomohy 
Sumontha, Vasaruchapong, Chomngam, Suntrarachun, Pawangkhanant, Sompan, Smits, Kunya & Chanhome, 2020

Omkoi Lance-headed Pit Viper | งูเกอะลออมก๋อย ||

Protobothrops kelomohy sp. nov. is described from dry evergreen forest in Chiang Mai Province, northern Thailand, based on morphology and a molecular phylogeny. It differs from congeners by the following combination of characters: 1) relatively large body size (total length up to 1,310 mm); 2) dorsal scale rows 23–23–17, all keeled; 3) ventral scales 231–234; 4) subcaudal scales 80–84, paired; 5) supralabials 8–9; 6) infralabials 12–13; 7) typical lance-pattern on upper head surface; 8) three bold vertical facial stripes; and 9) dorsal and tail brown, each scale with dark reddish-brown transverse blotches, edged in black, somewhat fused together as a median zigzag line on dorsum, a row of large ventrolateral blotches on each side, each darker marking edged by a narrow yellow line. The new discovery and other recent findings suggest that further herpetological research is required in the montane forest of northern Thailand and adjacent Myanmar and Laos. Data on the natural history of the new species and an updated key to the species of Protobothrops are provided. This is the second species of Lance-headed Pit Viper recorded from Thailand after P. mucrosquamatus.

Keywords: Protobothrops, Crotalinae, new species, montane forest, Thailand

photo by P. Pawangkhanant

FIGURE 2. Holotype male of Protobothrops kelomohy sp. nov. (QSMI 1557) in life (photo by M. Sumontha).

FIGURE 4. Living juvenile of Protobothrops kelomohy sp. nov.A) PMU04 in situ , not preserved (photo by M. Sumontha); B) in situ, from Tha Song Yang district, Tak Province (photo by T. Smits)

Protobothrops kelomohy sp. nov.

Diagnosis. – Protobothrops  kelomohy sp. nov. differs from other species of the genus by  the  combination  of  the  following characters: 1) relative larger body size (TL up to 1310 mm); 2) dorsal scale rows 23–23–17, all keeled; 3) ventral scales 231-234; 4) high number of subcaudals (80-84 pairs); 5) 8-9 supralabials; 6) 12-13 infralabials; 7) typical  lance-head  pattern  on  upper  head surface; 8) three bold vertical facial stripes, (first from internasal, second from facial pit, third from eye) and a bold postocular stripe extending obliquely downwards on temporal region then curved down immediately at the end of the last supralabial; 9) dorsal body and  tail  reddish-brown,  each  scale with black edges; transverse blotches, somewhat fused together as a zigzag median line on dorsum and a row of large ventrolateral blotches on each side, each darker marking edged with a narrow yellow line.

Etymology. – The specific epithet "kelomohy" is taken from the romanized nouns “kə̀lɔ” meaning “fire or thunder” and “môhɨ” meaning “mothers that lay eggs and stays and look after them during incubation time until hatching”. The first noun is drawn from the vernacular name of the new species in the Northern Pwo Karen language, a language of Karen subfamily, Sino-Tibetan family, and probably refers to the snake bite’s inducing an immediate sharp, burning pain. The second noun refers to the maternal reproductive behavior of the genus Protobothrops, assumed to be the same for the new species. 
Suggested common names are Omkoi Lance-headed Pit Viper (English), Ngoo Kelo Omkoi - งูเกอะลออมก๋อย (Thai),  and Yum Kelo Mo Hy - ฌู่งเก่อลอโม้ฮือ (Karen). งูเก่อลอโม่ฮือ ฅื่อเกอะลอโม่ฮือ เกอลอมอฮือ กอลามอฮือ

Distribution and natural history. – All specimens  of Protobothrops kelomohy sp. nov. in this report were found in Sop Khong Subdistrict,  Omkoi  District,  Chiangmai Province, Thailand, a mountainous area that has an  estimated  elevation  range  between 600–1,200 m a.s.l. (red solid circle in Fig. 5). The holotype male (QSMI 1557) and referred juvenile (PMU04) (Fig. 4A) were found on the ground near a rock and a shrub respectively at night in dry evergreen forest, in the vicinity of human dwellings (Fig. 6). This snake is also known by locals from adjacent mountainous area for which we found evidence through two other specimens, a juvenile and an adult, that were found in Tha Song Yang District, Tak Province, Thailand (red hollow circle in Fig. 5). The adult, from Tha Song Yang, was found on a road late at night, 2:30 AM, still alive, but fatally injured by a vehicle. The juvenile, from Tha Song Yang, was found nearby at night in ambush position on a limestone rock on a forested slope (Fig. 4B). The Tha Song Yang specimens were not examined as referred specimens, because the adult specimen carcass was badly damaged by a vehicle and the juvenile specimen was photographed, but not collected because it was found near a wildlife protection area. Other snakes found in the same habitat at the type locality during the survey included Ovophis monticola (Günther),  Trimeresurus [Popeia] popeiorum (Smith) (Viperidae), Pareas hamptoni (Boulenger), P. margaritophorus (Jan) (Pareatidae), Rhabdophis chrysargos (Schlegel), Xenochrophis piscator (Schneider) (Natricidae), Boiga cyanea (Duméril, Bibron and Duméril), B. multomaculata (Boie), Lycodon laoensis (Günther), L. septentrionalis (Günther), Oligodon cf. fasciolatus (Günther), Ptyas korros (Schlegel) (Colubridae), and lizards included Cyrtodactylus inthanon (Gekkonidae), Acanthosaura sp., Calotes emma alticristata (Schmidt), Draco blanfordii  (Blanford)  and Dtaeniopterus (Günther) (Agamidae).

photo by Ton Smits 

Montri Sumontha, Taksa Vasaruchapong, Niruth Chomngam, Sunutcha Suntrarachun, Parinya Pawangkhanant, Weerasak Sompan, Ton Smits, Kirati Kunya and Lawan Chanhome. 2020. Protobothrops kelomohy sp. nov. (Squamata: Viperidae), the Second Known Species of Lance-Headed Pit Viper from Thailand. Tropical Natural History. 20(1); 43-59.