Ichthyophis sp.

Geissler, Peter, Poyarkov, Nikolay A., Grismer, Lee, Nguyen, Truong Q., An, Hang T., Neang, Thy, Kupfer, Alexander, Ziegler, Thomas, Böhme, Wolfgang & Müller, Hendrik, 2015, New Ichthyophis species from Indochina (Gymnophiona, Ichthyophiidae): 1. The unstriped forms with descriptions of three new species and the redescriptions of I. acuminatus Taylor, 1960, I. youngorum Taylor, 1960 and I. laosensis Taylor, 1969, Organisms Diversity & Evolution (New York, N. Y.) 15 (1), pp. 143-174 : 156-160

Ichthyophis sp. Neang, Grismer, Chan, Grismer, Wood & Youmans, 2010: 127.

Holotype Metamorphosed female ( LSUHC 9335 ), collected on 7 July 2009 by Lee L. Grismer, Chan Kin Onn, Jesse L. Grismer, Perry L. Wood Jr., Neang Thy and Timothy M. Youmans at Dalai Mountain (12°26′ 134″ N 103° 03′ 217″ E; elevation, 968 m), Phnom Samkos Wildlife Sanctuary, Cardamom Mountains, southwestern Cambodia (see Fig. 1).

Paratypes CBC 01185 , adult female ( Fig. 7 ), collected by Neang Thy and Kris Mean Rith on 12 September 2010 in O’ Peam area (12° 12′ 15″ N 103° 4′ 12″ E; elevation, 293 m) . LSUHC 10106 , adult female, collected on 22 August 2011 by Neang Thy, Lee L. Grismer, Evan S.H. Quah and Jeff Dawson in O’ Som area (12° 04′ 6.18″ N 103° 09′ 30.24″ E). All were found in the Phnom Samkos Wildlife Sanctuary, southwest Cardamom Mountains, Pursat Province, Cambodia .

Diagnosis A species of Ichthyophis without a lateral yellow stripe; total length of metamorphosed specimens 183.0– 321.7 mm, length about 23–37 times of midbody width; snout blunt and rounded (SP/HL=0.04–0.09); TN/ ET =2.8–3.2; premaxillary and maxillary teeth 23–38, vomeropalatine teeth 28– 29, dentary teeth 20–34, inner mandibular teeth 19–22; inner mandibular tooth row shorter than dentary row; tail end somewhat tapered; total annuli (dorsal count) 322 to 364, not encircling body ventrally, except the posteriormost 60 grooves, which are continuous across venter in a straight line, four to five annuli interrupted by cloacal disc, four to six tail annuli posterior to the cloacal disc; cloacal disc triangular in shape; 120 vertebrae; scales in one series per annulus (dosolaterally), present only in the posterior half of body. The species differs from all other known unstriped congeners in the following characters: from I. acuminatus by a larger eye size (HL/ ED =11.5–13.2 vs. 20.9), more vertebrae (120 vs. 109–111) and a higher number of total annuli (322–364 vs. 296–327) (additional specimens have to confirm the diagnostic value of the latter two characters); from I. catlocensis sp. nov. by having a smaller TN/ ET ratio (2.8–3.2 vs. 4.5); from I. billitonensis by more inner mandibular teeth (19–22 vs. 2); from I. bombayensis by the absence of scales in the anterior half of body; from I. chaloensis sp. nov. by a larger eye size (HL/ ED =11.5–13.2 vs. 31.3) and a smaller snout projection (SP/HL=0.04–0.09 vs. 0.14); from I. dulitensis by the absence of scales in the anterior half of body; from I. glandulosus by more vertebrae (120 vs. 102); from I. javanicus by the tentacle being situated closer to the eyes ( TN / ET =2.8–3.2 vs. 2.3); from I. lakimi by more inner mandibular teeth (19–22 vs. 14); from I. laosensis by the absence of scales on the anterior half of body; from I. larutensis by the presence of inner mandibular teeth; from I. monochrous by the absence of scales on the anterior half of body and more annuli (322–364 vs. 247); from I. orthoplicatus by more annuli (322–364 vs. 205–291); from I. sikkimensis by more annuli (322–364 vs. 276–292); from I. singaporensis by the absence of scales on the anterior half of body; from I. sumatranus by the absence of scales on the anterior half of body; from I. weberi by the presence of inner mandibular teeth; from I. youngorum by having more vertebrae (120 vs.108).

Description of holotype Selected morphological and meristic data are given in Table 4. Condition of the preserved specimen: small incisions in both corners of mouth in order to open the mouth; two ventral longitudinal incisions (each about 20 mm in length), first situated in midbody region, second in front of vent; some fat body lobes protrude out of the first incision; few opened scale pockets. Head (see Figs. 5 , 6 , and 7a) flattened, in dorsal view head broadens very slightly from first collar to corner of mouth, narrowing very slightly from corner of mouth to tentacles; snout bluntly rounded anterior to the tentacles in lateral view, head tapers slightly between first collar and nares; anterior to nares, snout drops down almost vertically, though slightly rounded; lips straight edged, corner of mouth somewhat closer to throat than to top of head; mouth almost terminal, snout barely projecting; in ventral view, gular region flattened, with a median depressed groove in extension of a more distinct groove on first collar, reaching about the position of tentacles; triangular depression of gular skin present between corners of mouth; eyes covered by unpigmented skin, rounded, lens forming a grey, round central disc, elevat- ed above surrounding skin; in lateral view, eyes closer to top of head than to upper lip; tentacle aperture 3.2 times closer to eye than to naris, close to upper lip, smaller than eyes, about the size of the naris; tentacular aperture elevated from surrounding skin, visible in lateral, dorsal and ventral view; in preservative, tentacles not protruding from tentacular aperture; nares oval in shape, closer to top of head than to upper lip, barely visible in dorsal view, not visible in ventral view; teeth ( Fig. 5a ) small, recurved and bicuspid, main cusp twice as long as accessory cusp; 23 teeth in premaxillary-maxillary, 20 in dentary, 29 in vomeropalatine, and 19 in inner mandibular series; teeth in premaxillary-maxillary and dentary series larger than teeth in vomeropalatine and inner mandibular series; length of premaxillary-maxillary tooth row about three quarters of vomeropalatine row; length of inner mandibular tooth row about half of dentary row; palate highly arced; choanae oval, proximately posterior to tentacles, surrounded by a bulged margin of palatal skin; tongue triangular with a median depression on the posterior two thirds of its length; one protruding, rounded patch of glandular skin anterior on each side of the depression; collar region wider and deeper than head and adjacent part of body; first collar groove incomplete, running up the lateral sides but fading towards the mediodorsal region, visible from above, but only on the outer edges of dorsum; second collar groove incomplete, fading completely on the ventral halves of flanks, not visible from above; both collar grooves visible in ventral view, each forming a slight curve towards head; median gular depression continuous along midline on first collar, fading on second; nuchal region bordered by the anteriormost annular groove posteriorly; no dorsal transverse groove on second collar; second collar longer than first, in ventral view; first as well as subsequent annular grooves not encircling the belly; total annuli 322/320 (dorsal count/ventral count); vertebrae 120; grooves encircling the venter in a straight line on the last 20 mm anterior to cloacal disc; slight depression along midline of venter present along the anterior 120 mm of trunk; on dorsum, grooves cross in an even double-S form, slightly curving posteromedially along the vertebral line; longitudinal cloacal slit situated in a triangular shaped cloacal disc, interrupting six annuli; cloaca surrounded by 5/6 (right/left) denticulations ( Fig. 6a ); tail bearing six annuli, terminating in a distinct, nipple-like tail cap; posteriormost annular groove, anterior to cap, not encircling the ventral side of tail; scales present only in annuli of the posterior half of body, small, oval in shape, present in one row in each scale pocket (counted dorsolaterally).

340), and higher tooth counts (see Table 4). However, both resemble the holotype in several characteristic features: TN/ ET 2.9 and 2.8; HL/ED 13.2 and 11.5; their coloration as well as in the shape of the annuli (grooves not completed on venter of the anterior two thirds of body); the absence of scales on anterior half of body, and the presence of a single scale row per pocket on the posterior part of body; the presence of a pair of rounded patches of glandular skin on the tongue.

Coloration In preservative: blackish grey on dorsum, light grey on belly; cloacal disc whitish, triangular; terminal cap white; eyes, tentancles and nares encircled by a narrow whitish margin (see Fig. 7 ). In life: body uniform, pinkish hazelnut brown; color brightening up on flanks and belly; annular grooves somewhat lighter than annular coloration; nares, lips and tentacles whitish pink (see Fig. 8 ).

Variation Selected morphological and meristic data are given in Table 4. The paratypes CBC 01185 and LSUHC 10106 (both adult females) have a higher number of annuli (364 and Natural history The holotype was found at day time in damp soil under a fallen log at a hillside, at an elevation of 986 m in an undisturbed evergreen forest, near a small, rocky, fastmoving stream. Paratype CBC 01185 was found in the morning (at 7:00 a.m.) in one of 20 pitfall traps (60 cm deep and 30 cm in diameter) set at an interval of 5 m, 40 m away from and parallel to a slow moving stream in lowland disturbed evergreen forest (elevation, 293 m). Paratype LSUHC 10106 was found during the day within a rotting log in hilly, disturbed evergreen forest at 528 m.

Etymology We name this new species after the geographic region of its known distribution, the Cardamom Mountains in western Cambodia, one of the most significant areas for the conservation of Cambodia’ s unique herpetofaunal diversity ( Neang et al. 2010).

Figures

Fig. 7 a–f Holotype (LSUHC 9335) of Ichthyophis cardamomensis sp. nov. in preservative (TL, 183.0 mm). Photographs by PG

Fig. 5 a–f Jaws of the holotype of (depicted characters are also present in the respectively investigated paratype specimens): a Ichthyophis cardamomensis sp. nov. (LSUHC 9335), b Ichthyophis catlocensis sp. nov. (ZFMK 88976), c Ichthyophis chaloensis sp. nov. (IEBR A.2011.16), d Ichthyophis laosensis (MNHN 1928.95), e Ichthyophis acuminatus (AMNH A20875), and f Ichthyophis youngorum (FMNH 189250). Drawings by PG

Fig. 6 a–f Tail region (in ventral view) of the holotype specimens of: a Ichthyophis cardamomensis sp. nov. (LSUHC 9335), b Ichthyophis catlocensis sp. nov. (ZFMK 88976), c Ichthyophis chaloensis sp. nov. (IEBR A.2011.16), d Ichthyophis laosensis (MNHN 1928.95), e Ichthyophis acuminatus (AMNH A20875), and f Ichthyophis youngorum (FMNH 189250). Drawings by PG

Fig. 8 Paratype (CBC 01185) of Ichthyophis cardamomensis sp. nov. in life (TL, 321.7 mm). Photograph by NT