Boiga stoliczkae ( Wall, 1909 )

Köhler, Gunther, Charunrochana, Panupong Thammachoti, Mogk, Linda, Than, Ni Lar, Kurniawan, Nia, Kadafi, Ahmad Muammar, Das, Abhijit, Tillack, Frank & O’Shea, Mark, 2023, A taxonomic revision of Boiga multomaculata (Boie, 1827) and B. ochracea (Theobald, 1868), with the description of a new subspecies (Squamata, Serpentes, Colubridae), Zootaxa 5270 (2), pp. 151-193 : 180-183

Boiga stoliczkae ( Wall, 1909)

Stoliczka´s Asian Cat Snake

1909 [ Dipsadomorphus ] stoliczkae Wall : 155.

Geographic distribution. In the west from central Nepal (ca. 83°51’E) through Darjeeling, Sikkim and Bhutan to Arunachal Pradesh and Assam in northeastern India (north and west of the Brahmaputra valley) (own observation; Wall 1909; Smith 1943; Fleming, JR. & Fleming, SR. 1974; Kramer 1977; Ahmed & Dasgupta 1992; Bauer & Günther 1992; Gruber 2002; Shah & Tiwari 2004; Whitaker & Captain 2004; Sanyal & Gayen 2006; Agarwal et al. 2010; Purkayastha 2013; Wallach et al. 2014; Das et al. 2016; Wangyal & Das 2021).

Type material. Wall (1909:155) mentioned that he has examined 39 specimens of this new species from the “neighbourhood of Darjiling” (Darjeeling, West Bengal state, India), which is characterised by having 21 [midbody] scale rows, 218–252 ventrals and 100–119 subcaudals. He did not specify particular specimens by inventory number and with the exception of the British Museum (Natural History) he does not mention any other collection in which the type material could be deposited. However, it is documented through his publications (e.g., Wall 1909; 1921) that he examined for his studies not only his own material but beside specimens from the British Museum also material from various collections in India (e.g., BNHS Mumbai, ZSI Kolkata, and St. Joseph’s College in Darjeeling). After his retirement in 1925 he presented parts his own collection, including type specimens, to the British Museum (Natural History) in London ( Smith 1951). Based on information provided by Andrew Stimson, Curator of Herpetology at the BMNH, Kramer (1977:735) was the first to mention inventory numbers for the type material of D. stoliczkae and regarded a series of eight specimens, i.e., BMNH 72.4.17.119, 72.4.17.386, BMNH 74.4.1193–94, BMNH 94.12.31.55, and 1909.3.13 –15 as syntypes. The two specimens mentioned by Wall (1909) and already considered by him as doubtful with respect to the locality “ Burma “, refer to BMNH 74.4.1193–1194 and were presented by R.H. Beddome (see also Introduction, and Wall 1908:714 footnote; Wall 1910:791 footnote). All aforementioned specimens are also marked as syntypes in the inventory ledger of the herpetological collection of the BMNH, now NHM London. However, some other specimens must also be regarded as part of the original series of D. stoliczkae , since they came from “Darjeeling“ and where part of Wall´s donation to the collection in London, registered in 1930, viz. BMNH 1930.5.8.648–649, 1930.5.8.650, and 1930.5.5.651. Thus, the material in the NHM London alone represents only a portion of the original specimens examined by Wall. Therefore, we also consider specimens in Indian collections as potential type material of D. stoliczkae that could have been available to Wall if the temporal context, locality, and morphological characters are consistent with those in his original description. Putative syntypes that fit Wall’s diagnosis, were collected in the “neighbourhood of Darjiling”, and which were already in the respective collection prior to 1909 include BNHS 1772 from “Tindharia” (~ 20 km southeast of Darjeeling), and ZSIK 7869, 7873, 7878, 8476 and 11367 all from “Darjeeling”.

In agreement with Art. 74.7 of the Code, we here designate BMNH 94.12.31.55 ( Figs. 17 and 18 ) as lectotype of Dipsadomorphus stoliczkae Wall, 1909 to introduce a standard of application for the species group name stoliczkae Wall by a single name-bearer.

Lectotype. BMNH 94.12 .31.55 ( Figs. 17 and 18 ), an adult male from “ Darjeeling ” (West Bengal state, India), presented by William Thomas Blanford.

Paralectotypes. BMNH 72.4 .17.119 and 72.4.17.386, both females from „Darjeeling“, presented by T.C. Jerdon; BMNH 74.4.1193–1194, both females from „ Burma “ [in error, most probably from the Eastern Himalayas ], presented by R.H. Beddome; BMNH 1909.3.13 –15, halfgrown, one female and two with unknown sex ; BMNH 1930.5.8.648–649, two skulls, 1930.5.8.650, genitals, and 1930.5.5.651, three vertebrae, all from „ Darjeeling “ collected and presented by F. Wall ; BNHS 1772 , a female from „Tindharia, Darjeeling“, collector unknown ; ZSIK 7869 , male, 7873, 7878, 8476 and 11367 all females from „Darjeeling“ collected and presented by British botanist George Alexander Gammie (1864–1935) .

Description of the lectotype. Adult male, indicated by the presence of hemipenes; 1/1 loreal, wider than high; nasal scale completely divided; 1/1 preocular; 1/1 supraocular; 2/2 postoculars, upper not reaching onto top of head; 2 prefrontals; 2/2 anterior and 2/3 posterior temporals; supralabials 8/8, 3 rd –5 th supralabials entering eye; 11/11 infralabials, first four in contact with anterior chin shields; 21 dorsal scales in 19-19-15 rows, smooth with single tiny apical pits on body and single or paired apical pits on dorsocaudal scales; vertebral scale row significantly enlarged; no preventral; 235 ventrals; cloacal plate entire; 111 paired subcaudal scales. Body slender; tail long (TL/ SVL 0.282); SVL 740 mm; TL 209 mm; head length measured from tip of snout to posterior border of parietals 16.5 mm, head length measured from tip of snout to posterior edge of mandible 21.8 mm, head width 13.0 mm; diameter eye 3.9 mm; distance anterior border eye to tip of snout 5.2 mm.

Maxillary bone with 10/11 prediastemal teeth, followed by a very distinct diastema which is 125% longer than the socket of the last prediastemal tooth and followed by two distinctly enlarged, grooved and posteriorly bent postdiastemal teeth. Prediastemal teeth slightly decrease in size posteriorly, the anterior two distinctly posteriorly hooked, the following with less pronounced curvature. On the left side, prediastemal teeth number one, three, five and seven missing, teeth six and eight broken, tooth nine and first postdiastemal tooth loose. On the right side, prediastemal teeth two, four, six, eight, 10 and first postdiastemal tooth loose. Medial to each maxillary tooth is a single replacement tooth at different growth stages.

Palatine bone with 6/6 posteriorly curved teeth, shorter that the prediastemal teeth and slightly decreasing in size posteriorly. Anterior two teeth missing on left side. Tooth two missing on the right side. Lateral to each palatine tooth is a single replacement tooth at different growth stages.

Pterygoid bone with 10/10 posteriorly curved teeth, shorter than the palatine tooth, gradually decreasing in size posteriorly. Teeth two, four, six and eight loose on left side. Teeth two, four, six, seven and nine loose on right side. The posterior 49% of the pterygoid bone are without teeth.

Mandibular bone with 17/17 posteriorly curved teeth, shorter than maxillary teeth, gradually decreasing in size posteriorly. Medial to each mandibular tooth is a single replacement tooth in different growth stages. Teeth one and two broken, teeth two, four, six, seven, nine, 11, 13 and 15 loose, and tooth 16 missing on left side. Teeth two, four, six, eight and nine loose, teeth 11, 13, and 15 missing on right side.

Coloration after about 130 years preservation in ca. 70% ethanol was recorded as follows: Dorsal ground color Cinnamon-Drab (Color 50) with Sepia (286) interstitial skin; dorsal head with same ground color as dorsal body, upper and lower labials Light Buff (2). Venter of head, body and tail Light Buff (2) without markings.

Dorsal scale reduction formula.

– 10+V(147) 3+4(152) – 8+V(192)

(10)21 ----------- 20 ------------- 19 ----------- 17 ------------ 16 ------------ 15(235).

3+4(142) – 3+4(152) 8+V(187) –

Variation. Paralectotypes and additional examined material agree well with the lectotype in general appearance, morphometrics and scalation ( Table 1 ).

Variation in dentition. Nine to 14 prediastemal teeth followed by a distinct diastema and two enlarged grooved postdiastemal teeth; five to eight palatine, nine to 15 pterygoid, and 15 to 21 dental teeth.

Variation in live coloration and pattern. Only a unicolored morph is known ( Fig. 19 ). The dorsal ground color may vary from Cinnamon (255) or Cinnamon-Rufous (31) to Tawny (60) in adults or Gem Ruby (65) in young individuals. Rarely a faint Cinnamon Brown (43) streak is running from the posterior border of the eye to the angle of the mouth. In some individuals a small faint banded dorsal body pattern is visible, which is caused by the Medium Neutral Grey (298) interstitial skin. Lower half of supralabials, infralabials, throat and first third of ventral body Pale Buff (1) or Chamois (84), rest of venter and tail Yellow Ocher (14) or Tawny Olive (17). Iris resembling the dorsal ground color of body and can vary from Cinnamon (255) to Gem Ruby (65); pupil Sepia (286).

Natural History. Boiga stoliczkae is mostly semiarboreal, crepuscular and nocturnal. It is known to inhabit open forest types, agricultural land, human habitations, and gardens, where it is found on low vegetation, bushes and walls. The altitudinal distribution ranges from lowlands, mid hills and submontane regions, from around 85 m up to 2000 m a.s.l. It is reported to feed on birds, their eggs, lizards, snakes ( Trachischium fuscum ), and small rodents (our observations; Shaw et al. 1941; Greene 1989; Tillack 1999; Gruber 2002; Jha & Thapa K. 2002; Shah & Tiwari 2004; Nepali & Singh 2020; Pradhan 2021).

Figures

FIGURE 17. Lectotype of Dipsadomorphus stoliczkae Wall (BMNH 94.12.31.55).A. dorsal view; B. ventral view. See text for details. Scale bar = 10 cm. Photos by FT.

FIGURE 18. Lectotype of Dipsadomorphus stoliczkae Wall (BMNH 94.12.31.55).A. dorsal view of head; B. right lateral view of head; C. left lateral view of head; D. ventral view of head. Scale bar = 1 cm. Photos by FT, line drawings by MOS.

FIGURE 19. Boiga stoliczkae in life. A. WIIAD 858, unsexed specimen from Royal Manas NP, Bhutan; B. ZMB 73660, a female from Naudanda, Kaski, Nepal, 1300 m a.s.l. Photo by AD (A) and FT (B).