Isanophis boonsongi (TAYLOR & ELBEL, 1958)
Can you confirm these amateur observations of Isanophis boonsongi?
|Higher Taxa||Colubridae (Natricinae), Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Common Names||E: Boomsong’s Stream Snake|
G: Boonsongs Bachnatter
|Synonym||Parahelicops boonsongi TAYLOR & ELBEL 1958: 1156|
Opisthotropis boonsongi — BROWN & LEVITON 1961
Parahelicops boonsongi — COX 1991
Opisthotropis boonsongi — COX 1995
Opisthotropis boonsongi — VAN DIJK et al. 1998: 48
Opisthotrophis [sic] boonsongi — CHAN-ARD et al. 1999: 35
Parahelicops boonsongi — DAVID et al. 2004
Opisthotrophis boonsongi — DAVID et al. 2011
Parahelicops boonsongi — WALLACH et al. 2014: 520
Parahelicops boonsongi — CHAN-ARD et al. 2015: 226
Isanophis boonsongi — DAVID et al. 2015
Type locality: Phu Lang (mountain), Ban Khok (subvillage), Na Phung (village), Dan Sai (district), Loei (province), Thailand [after BROWN & LEVITON 1961]
|Types||Holotype: FMNH 135328; formerly personal collection of E. H. Taylor (fide BROWN & LEVITON 1961)|
|Diagnosis||Diagnosis (genus): A genus of snake of the family Natricidae characterized by (1) posterior maxillary teeth strongly enlarged, (2) nostrils dorsolateral and directed obliquely upwards; (3) eye diameter slightly greater than the eye- nostril distance and distinctly greater than the distance between its lower margin and the margin of the lip, (4) pupil round, (5) dorsal scales strongly keeled with a thick median keel throughout the body, (6) body stout, (7) head strongly distinct from neck, and (8) prefrontal scale single [DAVID et al. 2015].|
Diagnosis. See above the generic characters plus: (1) large size, up to at least 990 mm; (2) 19–19–17 DSR, all strongly keeled; (3) 29 maxillary teeth in the holotype, the last three distinctly enlarged; (4) a long tail, with a ratio TaL / TL reaching at least 0.24; (5) 136–140 VEN, 60 SC in the holotype; (6) 8–9 SL; (7) 2 anterior temporals; (8) body uniformly dark ochre-brown (dark chestnut brown in life), somewhat paler and more beige on the lower part of the sides (dark reddish-brown); and (9) venter uniformly pale ochre-brown (pale yellowish-brown in life) [DAVID et al. 2015].
Comparisons (genera): Ren et al. 2019: 121 (Table 6) provide a morphological comparison of natricine genera (Opisthotropis, Paratapinophis, Isanophis, Trimerodytes balteatus, Hebius annamensis, Trachischium fuscum/guentheri, Rhabdops bicolor, Atretium yunnanensis, Pseudagkistrodon rudis multiprefrontalis).
Detailed description: Taylor & Elbel 1958: 1156.
Type species: Parahelicops boonsongi TAYLOR & ELBEL 1958: 1156 is the type species of the genus Isanophis DAVID et al. 2015.
Abundance: This species has been known from only the holotype until Cox (1995) recorded two additional specimens about 40 km east of the type locality. One of the specimens was depicted in Cox et al. (1998, 2012).
|Etymology||Named after Dr. Boonsong Lekagul who has so generously provided the University of Kansas with Thailand amphibians and reptiles.|
The generic nomen Isanophis is derived from the word “Isan”, the Thai name of the north-eastern region of Thailand, and from the Greek word ophis, meaning “snake”. It describes the limited known range of this genus. This generic nomen is masculine in gender.