Cryptic and non-cryptic diversity in New Guinea ground snakes of the genus Stegonotus Duméril, Bibron and Duméril, 1854: a description of four new species (Squamata: Colubridae) Author Ruane, Sara Author Richards, Stephen J. Author McVay, John D. Author Tjaturadi, Burhan Author Krey, Keliopas Author Austin, Christopher C. text Journal of Natural History 2017 J. Nat. Hist. 2017-11-27 52 13 - 16 917 944 http://dx.doi.org/10.1080/00222933.2017.1391959 journal article 10.1080/00222933.2017.1391959 1464-5262 5174516 9E21390E-3FD4-40EB-9442-31BC92A76B4F Stegonotus iridis sp. nov. ( Figures 2−5 , Table 1 , Appendix 1) Holotype MZB . Ophi. 3306 (field number SJR 7623 , tissue ABTC 90141 ), adult male. Collected by S. Richards , B. Tjaturadi and K. Krey on 9 June 2005 from Warinkabom , Batanta Island , Raja Ampat Regency , West Papua Province , Indonesia , elevation 50 m above sea level (asl) ( 0.836942°S , 130.72162°E ) ( Figure 5 ). Paratypes SAMA R 70466 (field number SJR 7514 , tissue ABTC 90088 ) collected by S . Richards, B . Tjaturadi and K . Krey on 5 June 2005 from Waire Camp , Batanta Island , Raja Ampat Regency , West Papua Province , Indonesia , elevation 25 m asl ( 0.839738°S , 130.525546°E ); MZB . Ophi . 3305 (field number SJR 7624 , tissue ABTC 90142 ) collected by S . Richards, B . Tjaturadi and K . Krey on 11 June 2005 from Urbinasopen , Waigeo Island , Raja Ampat Regency , West Papua Province , Indonesia , elevation 45 m asl ( 0.337183°S , 131.258800°E ); MZB . Ophi . 3303 (field number SJR 7691 , tissue ABTC 90173 ) collected by S . Richards, B . Tjaturadi and K . Krey on 18 June 2005 from Yakut Camp , Batanta Island , Raja Ampat Regency , West Papua Province , Indonesia , elevation 55 m asl ( 0.895817°S , 130.641633°E ); MZB . Ophi .3311, MZB . Ophi . 3302 (field numbers SJR 7794 , tissue ABTC 90230 ; SJR 7793 , a b Figure 3. Map of New Guinea sampling localities for Stegonotus (a) and mtDNA + nucDNA maximum likelihood gene tree (b). Symbols for species/clades match those on the map; * indicates bootstrap values ≥ 70. For some localities, symbols were adjusted for better visibility and so localities are approximate; see Appendix 1. for exact locality information. Table 1. Morphological characters of Stegonotus examined.
Species n Rows Ventral Sub Supr Infr Pre Post Aps Ventral/sub pattern Labial pattern
S. diehli ** 5 15 162−170 73−85 7 8 1 1, 2 yes mostly unmarked cream/with grey some labials with grey
S. melanolabiatus 10 15, 17 179−197 89−98 7 , 8 8 , 9 1 , 2 2 yes marked with grey/dark grey labials dark grey or mottled
sp. nov.** S. derooijae 4 17 178−197 90−94 7 , 9 8, 9 2 2 no† marked with grey/with grey labials grey or yellow mottled
sp. nov.*
S. modestus ** 8 17 183−214 60−88 7 , 8 8, 9 , 10 1, 2 2 no unmarked cream/with some grey with grey wash over labials
S. iridis 7 17, 19 198−211 78−88 8 9, 10 2 2 no unmarked white/unmarked white some grey/brown labials
sp. nov.*
S. admiraltiensis 4 17, 19 202−214 93−98 8,9 10 2 2 yes unmarked cream/unmarked unmarked labials
sp. nov.*
S. cucullatus ** 3 17 190−194 80−86 8 , 9 9, 10 2 2 no unmarked cream/unmarked with grey wash over labials
S. guentheri * 3 15 182−186 75−76 8 9 1 , 2 2 no unmarked cream/unmarked some labials with grey
S. heterurus * 1 17 197 89 7 9 2 2 no unmarked dark grey/very dark supr. dark grey, infr with grey
S. parvus ** 5 17 173−180 89−102 8 , 9 10 2 2 no unmarked cream/unmarked labials darker, some with mottle
S. batjanensis 12 17 207−229 82 − 90 7, 8 9, 10 1 , 2 2 yes unmarked yellow/edged with grey labials with dark edges
S. borneensis 3 17 192−217 61−80 9 10 2 2 no edged in grey/edged in grey with grey wash over labials
S. florensis 1 21 229 83 9 10 2 2 no edged in grey/grey wash labials with dark marks
S. muelleri 1 17 235 85+ 8 10 2 2 no mottled grey/dark grey supr. dark dorsally, infr. with grey
Includes number of individuals examined for morphology ( n ), number of midbody dorsal scale rows (rows), range of ventral scale number (ventral), range of subcaudal scale number (sub), number of supralabial scales (supr), number of infralabial scales (infr), number of preocular scales (pre), number of postocular scales (post), presence of apical pits (aps), generalized ventral/ subcaudal patterns (venter/sub pattern) and generalized labial patterns (labial pattern). New Guinean species indicated by *, mainland New Guinea by**. In cases of multiple numbers of scales the number in bold type represents the majority of specimens examined here. Specifics for individual specimens and additional morphological characters are in Appendix 1. A single Stegonotus derooijae sp. nov. was found with apical scales present, indicated by †. tissue ABTC 90229 ), collected by S . Richards, B . Tjaturadi and K . Krey on 27 and 28 June 2005 from Waibya , Salawati Island , Raja Ampat Regency , West Papua , Indonesia , elevation 75 m asl ( 0.956383°S , 130.784333°E ) . Referred specimens MZB .Ophi. 3301 ( SJR7805 , morphology only), collected by S . Richards, B . Tjaturadi and K . Krey on 27 and 28 June 2005 from Waibya , Salawati Island , Raja Ampat Regency , West Papua , Indonesia , elevation 75 m asl ( 0.956383°S , 130.784333°E ) .
Diagnosis A new species of Stegonotus that can be diagnosed from its congeners by the following combination of characters: a completely white or white with a brownish washed, iridescent dorsum, with or without brown or black speckling which increases posteriorly, an immaculate white venter and white subcaudal scales or, in individuals that are more heavily pigmented dorsally, a white venter with a brownish wash increasing in intensity posteriorly, brown or black pigmentation on the dorsal scales of the head (including rostral, internasal, prefrontal, frontal, parietals, loreal, supralabial and ocular scales) usually extending down the neck two or three scale rows before fading away, 19 dorsal scale rows at midbody (infrequently 17), the absence of apical pits on dorsal scales, 198−211 ventral scales and 78−88 divided subcaudal scales, eight (infrequently nine) supralabial scales and 10 (infrequently nine) infralabial scales, with supralabial scales brownish or blackish and infralabial scales either white or, in highly pigmented individuals, brownish or blackish. Description of holotype Adult male in excellent state of preservation, with a short ventral slit midbody and hemipenes exposed, not fully expanded. Body shape is robust. Snout–vent length 713 mm with 201 ventral scales, tail length 238 mm with 88 divided subcaudal scales. Anal scale single. Head length 28.3 mm , as measured from the snout to the rear of the quadrate, width 14.9 mm as measured across the widest point of the head anterior to the quadrate. Eyes 3.6 mm horizontal diameter, pupil shape subcircular. Supralabials eight with the fourth and fifth in contact with the eye. Infralabials 10, with first pair in contact behind mental, infralabials one to five in contact with inframaxillaries. Rostral broader than high, 5.6 mm wide/ 4.5 mm high, visible from above. Nasal in contact with first supralabial. Single loreal, in contact with nasal, preoculars, prefrontal and supralabials one, two and three and slightly extending as to barely contact the eye. Circumoculars five: one supraocular, two preoculars, zero suboculars and two postoculars. Anterior temporals two. Dorsal surface of head includes pair of internasals (width 3.6 mm /length of suture 1.4 mm ), pair of prefrontals (width 5 mm /length of suture 4.4 mm ), pair of supraoculars (width 2.7 mm /length 4.1 mm ), frontal longer than wide (length 6.5 mm /anterior width 6.4 mm ), pair of parietals (length of suture 7.9 mm ). Two pairs of inframaxillaries (anterior inframaxillary suture length 4.2 mm , posterior inframaxillary suture length 2.9 mm ), posterior inframaxillaries in contact with each other. Dorsal scale rows 17−19−15 (15th ventral from anterior, midbody, and 15th ventral anterior to cloaca). Coloration in life Dorsal coloration behind head white with no pattern or markings. Colour of iris black. Dorsum of head, including rostral, internasals, prefrontals, frontal, supraoculars and parietals, brown with white edges at the suture of most scales; several scales immediately posterior to the head with brown edges. Supralabials light brown/tan, infralabials white with light brown/tan pigment towards the ventral side of the scales. Ventral and subcaudal scales immaculate white and iridescent. Coloration in preservative Dorsal coloration in preservative of body posterior of head iridescent white with no pattern or markings down the entire dorsal side of the body and tail. Colour of iris opaque grey. Dorsum of head, including rostral, internasals, prefrontals, frontal, supraoculars and parietals, similar to coloration in life: brown with white edges at the suture of most scales; several scales immediately posterior to the head with brown edges. Supralabials light brown/tan, infralabials white with light brown/tan pigment towards the ventral side of the scales. Ventral and subcaudal scales immaculate white and iridescent. Variation Paratypes are similar to the holotype excepting the following: MZB.Ophi.3305 with 17 rather than 19 midbody dorsal scale rows, possibly nine rather than eight supralabials on the left (unclear), darker head pigmentation, dark speckling increasing posteriorly and a brownish-grey wash on the ventral and subcaudal scales; MZB.Ophi.3302, MZB.Ophi.3311, and MZB.Ophi.3301 with a brownish wash on the dorsal scales SAMA R70466 with 206 ventrals, 69 subcaudals (missing tail tip); MZB.Ophi.3305 with 198 ventrals, 78 subcaudals; MZB.Ophi.3303 with 203 ventrals, 83 subcaudals (missing tail tip); MZB.Ophi.3302 with 205 ventrals, 85 subcaudals; MZB.Ophi.3311 with 204 ventrals, 85 subcaudals; MZB.Ophi.3301 with 211 ventrals, 85 subcaudals. Etymology The species epithet is a noun in apposition and taken from the Latin word for rainbow. It refers to the high level of iridescence shown both dorsally and ventrally by this species. Natural history and distribution Currently known only from the Raja Ampat islands of Batanta, Salawati and Waigeo in eastern Indonesia where all of the animals encountered were active on the forest floor in moderately to heavily disturbed lowland (< 100 m asl) rainforest at night. The pale colour of this species made them extremely conspicuous against the dark forest floor. Comparisons The white or off- white dorsal and ventral colour of Stegonotus iridis sp. nov. , with a dark coloured head that includes white edges on most head scales, is unique for the genus. Although S. cucullatus has a pale phase that includes cream or yellowish-tan coloured dorsal scales with black edges resulting in a reticulated dorsal pattern ( Figure 1 (a)), the base coloration is not as white and appears more cream to tan when compared with S. iridis sp. nov. ( Figures 2 , 4 , 5 ).