Boiga multomaculata septentrionalis, Köhler & Charunrochana & Mogk & Than & Kurniawan & Kadafi & Das & Tillack & O’Shea, 2023

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 : 177-179

Boiga multomaculata septentrionalis ssp. nov.

Northern Polymorphic Asian Cat Snake urn:lsid:zoobank.org:act:439A42EE-0B42-4063-B04A-E18B14FA6023

1931 Boiga multomaculata indica Mell : 213 [partim].

1943 Boiga ochracea walli Smith : 349 [partim].

Geographic Distribution. As currently known, B. m. septentrionalis is distributed in northern Myanmar (Kachin state and Sagaing Region) and NE India (Assam and Nagaland), but is probably more widespread and based on the documented pattern of geographic distribution we have referred an adult male specimen from southern China ( CAS 242550 from Yunnan Province) tentatively to this subspecies, pending genetic confirmation.

Holotype. CAS 241272 , an adult male from Indawgyi Lake Wildlife Sanctuary (25.30347, 96.35417; 235 m a.s.l.), vicinity Kyang Kyar village , Moenyin Township, Myitkyina District, Kachin State, Myanmar, collected on 20 July 2008 by J.A. Wilkinson, J. V. Vindum, S.L. Oo, K. T. Kyaw, and M. Win. Original field tag MHS 25921.

Paratypes (3). CAS 241150 , an adult female from Indawgyi Lake Wildlife Sanctuary (25.30347, 96.35417; 235 m a.s.l.), E of Nat Mouk Kan village, Moenyin Township, Myitkyina District, Kachin State, Myanmar, collected on 14 July 2008 by G.O.U. Wogan, J.A. Wilkinson, J. V. Vindum, A.K. Shein . CAS 241550 , an adult female from Indawgyi Lake Wildlife Sanctuary (25.17869, 96.29156; 270 m a.s.l.), vicinity of Lwe Mon village , Moenyin Township, Myitkyina District, Kachin State, Myanmar, collected on 26 July 2008 by J.A. Wilkinson, K. T. Kyaw , and J. V. Vindum . SMF 106288 (formerly CAS 239222 ), an adult male from Linpha village (25,80489, 95,52667; 140 m a.s.l.), Hkanti Township, Hkanti District, Sagaing Region, Myanmar, collected on 10 September 2006 by K.S. Lwin, S.L. Oo, and A.K. Shein .

Diagnosis. A subspecies of Boiga multomaculata that differs from the other two subspecies (i.e., B. m. multomaculata and B. m. ochracea ) by mean pairwise genetic distances of 3.3–5.8% (ND4) and 3.7–6.5% (CYTB), respectively. It further differs from B. m. multomaculata by having on average more ventral scales in both sexes (males 227.7±5.19, females 228.8± 1.71 in B. m. septentrionalis versus males 214.4±8.06, females 217.1± 9.50 in B. m. multomaculata ), by having on average more subcaudal scales in both sexes (males 99.1±5.82, females 97.3± 2.06 in B. m. septentrionalis versus males 94.5±5.33, females 89.8± 4.13 in B. m. multomaculata ), and by having both blotched and patternless individuals (versus only blotched specimens in Boiga m. multomaculata ). It further differs from B. m. ochracea by having on average fewer ventral scales in females (228.8± 1.71 in B. m. septentrionalis versus 238.9± 6.30 in B. m. ochracea ).

Description of the holotype ( Figs. 14 and 15 ). Adult male, indicated by fully developed everted hemipenes; 1/1 loreal, wider than high; nasal scale partly divided below the naris; 1/1 preocular; 1/1 supraocular; 2/2 postoculars; 2 prefrontals; 2/2 anterior and 3/2 posterior temporals; supralabials 8/8, 3 rd –5 th supralabials entering eye; 11/11 infralabials, first five in contact with anterior chin shields; dorsal scales in 19-19-15 rows, smooth with single or paired apical pits on body and single to triple apical pits on dorsocaudal scales; vertebral scale row distinctly enlarged; two preventrals and 226 ventrals; cloacal plate entire; subcaudal scales 92, paired. Body slender; tail long (TL/SVL 0.235); SVL 578 mm; TL 136 mm; head length measured from tip of snout to posterior edge of mandible 18.1 mm, head width 10.5 mm; diameter eye 3.4 mm; distance anterior border eye to tip of snout 4.9 mm.

Dentition. Maxillary bone with 11/11 prediastemal teeth, followed by a distinct diastema which is 40% 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 three distinctly posteriorly hooked, the following with less pronounced curvature. On the left side, prediastemal teeth number two, four, six, eight and ten, and first postdiastemal loose. On the right side, prediastemal teeth one, three, five, seven and nine, 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 strongly curved teeth, shorter that the prediastemal teeth and slightly decreasing in size posteriorly. Tooth three six loose on left side. Teeth two, four and six loose on the right side. Lateral to each palatine tooth is a single replacement tooth at different growth stages.

Pterygoid bone with 11/12 posteriorly curved teeth, shorter than the palatine tooth, gradually decreasing in size posteriorly. Teeth two, five, seven and 10 loose on left side. Teeth one, three, five, 10 and 12 loose on right side. The posterior 63% of the pterygoid bone are without teeth.

Mandibular bone with 18/17 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, three, five, seven, nine, 11, 13 and 15 loose on left and right side. Tooth 17 missing on right side.

Coloration after about 13 years preservation in 70% ethanol was recorded as follows: Dorsal ground color Smoke Gray (Color 266) with Natal Brown (49) mottling on scales and with 62 Sepia (286) blotches that have a paler (Grayish Olive 274 suffused with Smoke Gray 266) center and a white to Pale Buff (1) border.

Dorsal scale reduction formula.

4+5(10)	–9(150)	2+3(158)
(5)21 ------------ 19 ----------- 17 ------------- 115(226).
4+5(10)	–9(152)	3+4(159)

Variation. Paratypes agree well with the holotype in general appearance, morphometrics and scalation ( Table 1 ). Most paratypes are blotched as is the holotype. An exception is SMF 106288 (formerly CAS 239222) that has no blotches but exhibits 58 indistinct transverse dark bars composed of dark edges of adjacent dorsal scales.

Variation in dentition. Ten to 12 prediastemal teeth followed by a distinct diastema and two enlarged grooved postdiastemal teeth; five to six palatine, seven to 12 pterygoid, and 16 to 19 dental teeth.

Variation in live coloration and pattern. Two color morphs, blotched and unicolored are known. The blotched morph resembles the color and pattern of brownish individuals of the nominate subspecies. The unicolored morph ( Fig. 16 ) resembles the unpatterned morph of B. m. ochracea .

An intermediate color variation is known from Nagaland, NE India ( WII-AD 856 ), which resembles the ground coloration of the unicolored morph but shows a Raw Umber (280) postocular stripe, faint dark dorsal had pattern similar to that of the nominate subspecies and an irregular strippled Raw Umber (280) pattern forming broken bands along dorsal body and tail .

Etymology. The species epithet is formed from the Latin words septentrio (= “north”) and the suffix - alis (to form an adjective) and refers to the geographic distribution of this taxon. Boiga m. septentrionalis has the most northern distribution of the subspecies of B. multomaculata .

Natural History. The holotype of B. m. septentrionalis was collected at 19:30 hrs. in bamboo, about 2 m above ground. The paratypes were all collected at night when Boiga is active. At the time of capture, the air temperature was 26.1–28.2°C and the relative air humidity was recorded as 81–96%.

Figures

FIGURE 14. Holotype of Boiga multomaculata septentrionalis ssp. nov. (CAS 241272). A. dorsal view; B. ventral view. See text for details. Scale bar = 10 cm. Photos by FT.

FIGURE 15. Holotype of Boiga multomaculata septentrionalis ssp. nov. (CAS 241272).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 16. Boiga m. septentrionalis from Nagaland, India, in life (WIIADR 856). Photo by AD.