Dendrelaphis proarchos Wall, 1909

(Figs 1A, B; 6A, B; 7B)

Dendrophis proarchos Wall, 1909: 347; 1910: 827.

Dendrophis proarchus – Wall 1921: 157.

Dendrelaphis proarchos – Vogel & van Rooijen 2011a. — Das 2012. — Hakim et al. 2020. — Jiang et al. 2020.

TYPE MATERIAL. — Not located. According to Vogel & van Rooijen (2011a), the specimen examined by Wall was from the collection of St. Joseph’s College, Darjeeling, India.

TYPE LOCALITY. —“Darjeeling,” State of West Bengal, India, by inference; unknown collector.

MATERIAL EXAMINED. — India • 1 ♀; Assam, Dibrugarh; BMNH1908.6.23.27 • 1 ♀; Mizoram, Aizawl District, Durtlang; 23°14’0”N, 92°43’31”E; 1215 m a.s.l.; 6.VI.2017; Lal Biakzuala leg.; GenBank: MT635656; MZMU951 • 1 ♂; MZMU1066; Mizoram, Siaha District, Phura; 22°13’57”N, 92°54’45”E; 226 m a.s.l.; 7.VIII.2016; M. Vabeiryureilai leg. • 1 ♀; Mizoram, Mamit District, Reiek-kai; 23°42’43”N, 92°39’49”E; 150 m a.s.l.; 16.III.2013; H. T. Lalremsanga leg.; MZMU1077 • 1 ♂; Mizoram; Aizawl District, Sailam; 23°21’10”N, 92°47’53”E; 1312 m a.s.l.; 15.V.2014; H. T. Lalremsanga leg.; MZMU1078 • 1 ♂; Mizoram, Serchhip District, Buangpui; 23°42’15”N, 92°45’0”E; 710 m a.s.l.; 4.VIII.2017; Vanlal Hrima leg.; MZMU1079 • 1 ♂; Mizoram, Aizawl District, Sateek; 23°32’49”N, 92°42’12”E; 909 m a.s.l.; 18.VIII.2018; Lal Muansanga leg.; MZMU1080 • 1 ♀; Mizoram, Mamit District, Reiek Community Reserved Forest; 23°41’48”N, 92°36’19”E; 1166 m a.s.l.; 21.V.2017; G. Z. Hmar leg.; MZMU1101 • 1♂; Mizoram, Aizawl District, Tlangnuam; 23°42’23”N, 92°42’54”E; 1040 m a.s.l.; 12.V.2018; Lal Biakzuala leg.; GenBank: MT647129; MZMU1218 • 1 ♂; Mizoram, Lunglei District, Thenhlum; 23°11’51”N, 92°34’59”E; 687 m a.s.l.; 17.VIII.2014; H. T. Lalremsanga leg.; MZMU1327; GenBank: MT311195 • 1 ♂; Mizoram, Aizawl District, MZU campus; 23°44’15”N, 92°39’45”E; 789 m a.s.l.; 21.V.2019; Lalrinsanga leg.; GenBank: MT647128, MT711166; MZMU1370 • 1 ♀; Mizoram, Aizawl District, Maubuang; 23°29’15”N, 92°42’43”E; 1012 m a.s.l.; Denzil Lalneihsanga leg.; GenBank: MT635657; MZMU1432 • 1 ♂; Mizoram, Khawzawl District, Khawzawl; 23°32’34”N, 93°10’51”E; 1225 m a.s.l.; 7.VII.2018; H. T. Lalremsanga leg.; MZMU1475 • 1 ♂; Mizoram, Aizawl District, Kepran; 23°56’40”N, 92°55’50”E; 1360 m a.s.l.; 9.III.2018; H. T. Lalremsanga leg.; MZMU1507 • 1 ♀; Mizoram, Saitual District, Tamdil National Wetland; 23°44’24”N, 92°57’5”E; 774 m a.s.l.; H. T. Lalremsanga leg.; GenBank: MT634738; MZMU1509 • 1♀, 1 ♂; Mizoram, Serchhip District, Leng; 23°9’20”N, 93°7’14”E; 1230 m a.s.l.; H. T. Lalremsanga leg.; MZMU1510, MZMU1529 • 1 ♂; Mizoram, Serchhip District, Khawlailung; 23°13’12”N, 92°59’33”E; 1035 m a.s.l.; H. T. Lalremsanga leg.; MZMU1516 • 1 ♂; Mizoram, Aizawl District, Sesawng; 23°45’34”N, 92°51’14”E; 853 m a.s.l.; 15.VIII.2015; Lalrinsanga leg.; MZMU1566 • 1 ♂; Mizoram, Aizawl District, Daifim resort; 23°47’59”N, 92°37’29”E; 70 m a.s.l.; 11.VI.2019; H. Laltlanchhuaha leg.; MZMU1598 • 1♂; Mizoram, Aizawl District, Tanhril; 23°44’12”N, 92°40’33”E; 958 m a.s.l.; 16.IX.2019; Lalrinsanga leg.; MZMU1602 • 1 ♂; Mizoram, Mamit District, Dampa Tiger Reserve; 23°43’28”N, 92°23’40”E; 255 m a.s.l.; 10.VI.2016; Ht. Decemson leg.; MZMU1603 • 1 ♀; Mizoram, Aizawl District, Sialsuk; 23°23’50”N, 92°44’46”E; 1255 m a.s.l.; 7.X.2019; Angshuman Das leg.; GenBank: MT274567; MZMU1629 .

Myanmar • 1 ♂; Sagaing Division; CAS210338; GenBank: KX660183, KX660456 (Figueroa et al. 2016) • 1 ♀; Ayeyarwady Division; GenBank: KX660182, KX660455; CAS222690 (Figueroa et al. 2016) .

Laos • 2 ♀; no locality information; MNHN1896.650; MNHN1896.651 • 1 ♀; Phongsaly Province, Buon Tai; MNHN2004.0253 • 1 ♀; Phongsaly Province, Long Nai; MNHN2004.0254; • 2 ♂; Phongsaly Province; MNHN2004.0263; MNHN2004.0251 .

Vietnam • 1 ♀; Tonkin; MNHN1948.82 .

DIAGNOSIS (BASED ON NEW MATERIAL). — From a total of 34 Dendrelaphis specimens collected from the Mizoram State, 22 of them were morphologically diagnosed as D. proarchos based on the combination of: 1) bronze-coloured body with bluish interstitial skin and a black lateral stripe separating cream dorsolateral stripe from whitish underside; 2) enlarged vertebral scales; 3) Ve 180-190 in males, 186-195 in females; 4) paired Sc 142-163 in males, 138- 146 in females; 5) undivided As in 36.4% of the specimens; 6) Ls single; 7) PrO 1; 8) PoO 2-3; 9) Te 2+2 or 2+3, rarely 3+2 or 1+2; 10) 4th–6th SLE; 11) IF 9-10, rarely 11; 12) SL 8-9; 13) DSR 15:15: 9 in males, 15:15: 11 in females, rarely nine rows in females; and 14) average relative RTaL 0.35 (0.31-0.37) in males, 0.33 (0.33- 0.34) in females. The hemipenis is not bilobate, and extends up to seven caudal plates; a prominent sulcus spermaticus runs up to the tip; a sinuous fold is present at about the middle of the organ, and the distal area is covered by somewhat evenly distributed small spines. The new materials divulged a new upper limit of Sc range i.e, 138-163 (sex pooled) vs 138-156 (Vogel & van Rooijen 2011a). However, other morphological characters of the new materials are consistent with the specimens from Assam (Northeast India), Myanmar, Laos and Vietnam (also see Vogel & van Rooijen 2011a).

GEOGRAPHICAL DISTRIBUTION. — Northeast India, Bangladesh, Myanmar, northern Laos, and northern Vietnam (Vogel & van Rooijen 2011a). In this study, we documented D. proarchos from 22 different localities at the elevation range between 60-1360 m a.s.l. from Mizoram, Northeast India (Fig. 5; Appendix 1).