Leptolalax (Lalax) lateralis ( Anderson, 1871 )

Humtsoe, Nzano, Bordoloi, Sabitry, Ohler, Annemarie & Dubois, Alain, 2008, Rediscovery of a long known species, Ixalus lateralis Anderson, 1871, Zootaxa 1921, pp. 24-34 : 27

Leptolalax (Lalax) lateralis ( Anderson, 1871)

Neotype IASST A.68, adult male, by present designation. – Type-locality: Nhyatsutchu stream, Wokha district, Nagaland, India (alt. 1315 m; near 26°06’N, 94°16’E).

Chresonymy. We cite here only the references which designate the biological taxon defined by our designation of onomatophore:

Ixalus lateralis Anderson, 1871: 29 . – Boulenger 1882: 103; Fea 1897: 90.

Leptolalax (Lalax) lateralis – Delorme, Dubois, Grosjean & Ohler 2006: 14.

Description of the neotype ( Fig. 1 ; Tab. 2 )

Size and general aspect. (1) Specimen of small size (SVL 28.0 mm); moderately stout.

Head. (2) Head wider than long (HW 9.1 mm, HL 8.7 mm, MN 7.3 mm, MFE 5.4 mm, MBE 2.45 mm), flat above. (3) Snout rounded, slightly protruding, its length (SL 4.1 mm) subequal to horizontal diameter of eye (EL 4.0 mm). (4) Canthus rostralis rounded, loreal region concave. (5) Interorbital space flat, less wide than upper eyelid (IUE 2.45 mm, UEW 3.1 mm), distance between upper eyelids wider than distance between nostrils (IN 2.5 mm). Distance between anterior borders of eyes (IFE 4.1 mm) 2/ 3 in distance between backs of eyes (IBE 7.7 mm). (6) Nostril rounded, without flap of skin, less close to tip of snout (NS 2.0 mm) than to eye (EN 1.85 mm). (7) Pupil vertical. (8) Tympanum distinct, rounded, its diameter half diameter of eye ( TYD 2.0 mm, TYE 1.1 mm). (9) Pineal ocellus absent. (10) Vomerine ridge absent. (11) Tongue large, spatulate, notched; median lingual process absent; tooth-like projection on maxilla absent.

Forelimbs. (12) Arm short (FLL 6.3 mm), shorter than hand (HAL 7.2 mm), forearm not enlarged. (13) Fingers thin, rather long (TFL 3.6 mm). (14) Relative length of fingers I<II<IV<III. (15) Tips of fingers rounded, thickened, without grooves. (16) Fingers without lateral dermal fringe; webbing absent. (17) Subarticular tubercles absent; longitudinal ridges under fingers present. (18) Palmar tubercles present, prominent; inner rounded, outer oval.

Hindlimbs.(19) Leg short, four times longer (TL 12.9 mm) than wide (TW 3.2 mm), tibia shorter than thigh (FL 12.4 mm) and than foot (FOL 12.0 mm). (20) Toes long (FTL 5.4 mm), less one third of length from heel to tip of toe IV (TFOL 17.4 mm). (21) Relative length of toes I<II<V<III<IV. (22) Tips of toes rounded, thickened, without grooves. (23) Webbing rudimentary, dermal fringes on toes poorly developed: I 2 - 2 1/ 2 II 2 - 3 III 2 2/3 - 4 IV 4 1/4 - 3 1/ 4 V (MTTF 4.45 mm, MTFF 4.55 mm, TFTF 6.3 mm, FFTF 6.55 mm). (24) Dermal fringe along toe V absent. (25) Subarticular tubercles absent; longitudinal ridges under toes. (26) Inner metatarsal tubercle distinct (IMT 1.6 mm), 1.25 times in length of first toe (ITL 2.0 mm). (27) Tarsal fold absent. (28) Outer metatarsal tubercle absent.

Skin. (29) Dorsal and lateral parts of head and body: snout between eyes and back roughly granular; side of head smooth; lower part of flank with large glandular warts. (30) Latero-dorsal folds absent; Fejervaryan line absent; supratympanic fold distinct, from back of eye, ending in a gland above shoulder (rictal gland). (31) Dorsal parts of limbs: forearms with glandular warts; hindlimbs with glandular warts and longitudinal folds. (32) Ventral parts of head, body and limbs smooth; thighs with large glandular zone near vent. (33) Macroglands: femoral, rictal and supra brachial glands present.

Coloration of preserved specimen. (34) Dorsal and lateral parts of head and body: dark brown with indistinct darker spots including a pair of spots between eyes and spots in shoulder region; loreal and tympanic region light brown with darker spots and bands; tympanum with dark brown spot; flanks light brown with never been reported subsequently from India, but recent surveys discovered specimens of this genus in various regions of North-East India. As Ixalus lateralis Anderson, 1871 is the first available nomen for a species of the genus Leptolalax Dubois, 1980 and of its subgenus Lalax Delorme et al., 2006 , it is important to define clearly this species. Thus we here designate a neotype and describe it in details.

Figures

FIGURE 1. Leptolalax lateralis (Anderson, 1871). Neotype IASST N 68, adult male, SVL 28 mm. Dorsal, ventral and lateral view. Photo N. Humtsoe.