Leptobrachium bompu, Sondhi, Sanjay & Ohler, Annemarie, 2011

Sondhi, Sanjay & Ohler, Annemarie, 2011, A blue-eyed Leptobrachium (Anura: Megophryidae) from Arunachal Pradesh, India, Zootaxa 2912, pp. 28-36 : 30-34

Leptobrachium bompu n. sp.

Material examined. One adult male, holophoront (holotype), no. KA0001/ 200905, locality: Bompu (27º06’61” N, 92º 40’64” E), altitude of 1940 m, coll. by Sanjay Sondhi on 22 May 2009 at 2000 hours, deposited in the State Forest Research Institute, Itanagar, Arunachal Pradesh. A tissue sample of this specimen has been taken for molecular phylogenetic analysis.

Two other frogs caught and examined but not collected, showed little variation from the holophoront in terms of size and coloration.

Etymology. This species is named after the type locality that it was discovered in, i.e. Bompu at Eaglenest. By naming it after the location it was found in, it is hoped that the local community in the area will continue with their significant efforts to conserve the forests in the area. The specific epithet is a noun in apposition, thus invariable.

Diagnosis. Leptobrachium bompu was placed in the genus Leptobrachium because of the following diagnosis: femoral gland present; oval flat axillary glands on flanks posterior to arm insertion present; rictal glands and ventrolateral glandular ridges absent; inner palmar tubercle circular of similar size to outer tubercle; vomerine teeth absent; snout and dermal palpebral projections absent; skin with fine ridges forming reticulum. It can be distinguished from the other species of Leptobrachium by the combination of the following characters; spines on upper lip absent in adult males; head wider than long; tympanum indistinct; second finger shortest; finger tips swollen; tibia longer than 40 % of snout-vent length; toe tips swollen; webbing leaving 3 ½ phalanges of toe IV and 2 phalanges of toe V free; length of inner metatarsal tubercle almost equals first toe length; dorsal pattern with irregular distinct darker markings; ventrum brown (in alcohol), dark purple (in life) with small white spots; iris of uniform grey-blue coloration; sclera black. The new species differs from all congeners by a combination of various morphological characters, besides its body and eye coloration; for comparisons, see Table 2.

Onymotope. Bompu (27°06’61” N, 92°40’64” E, altitude of 1940 m) in the Eaglenest Wildlife Sanctuary, West Kameng district, Arunachal Pradesh, India.

Description of the holophoront ( Figure 1–2 , Table 1): Size and general aspect: (1) Specimen of moderate size (SVL 47.0 mm), body rounded.

Head: (2) Head large, wider (HW 18.8 mm) than long (HL 16.9 mm; MN 13.5 mm; MFE 11.0 mm; MBE 5.0 mm), flat. (3) Snout rounded, not protruding; its length (SL 7.6 mm) longer than horizontal diameter of eye (EL 6.5 mm). (4) Canthus rostralis distinct, not prominent, loreal region flat; obtuse in cross section. (5) Interorbital space flat, larger (IUE 5.4 mm) than upper eyelid (UEW 3.9 mm) and than internarial distance (IN 4.7 mm); distance between front of eyes (IFE 6.3 mm) about two fifth of distance between back of eyes (IBE 14.0 mm). (6) Nostrils rounded, without flap of skin; slightly closer to eye (EN 4.8 mm) than to tip of snout (NS 5.5 mm). (7) Pupil oval, vertical. (8) Tympanum indistinct, not measured. (9) Pineal ocellus absent. (10) Vomerine ridge absent. (11) Tongue large, cordate, emarginate; median lingual process absent. (12) Supratympanic fold prominent from posterior corner of eye to forelimb.

Forelimbs: (13) Arm long, thin; fore-arm (FLL 12.2 mm) about as long as hand (HAL 12.8 mm), not enlarged. (14) Fingers I, II and IV short, thin, subequal in length; finger III long, thin (TFL 6.4 mm). (15) Relative length, shortest to longest: II <I <IV <III. (16) Tips of fingers I to IV rounded, slightly enlarged, without grooves. (17) Fingers with thick dermal fringes; webbing absent. (18) Subarticular tubercles absent, but callous ridges beneath all fingers and metacarpus present. (19) Prepollex rounded, prominent; a single, round, prominent palmar tubercle; supernumerary tubercles absent.

Hindlimbs: (20) Shanks rather long (tibiotarsal articulation reaching posterior corner of eye), four times longer (TL 20.9 mm) than wide (TW 5.7 mm), shorter than thigh (FL 24.4 mm) but longer than distance from base of internal metatarsal tubercle to tip of toe IV (FOL 19.8 mm). (21) Toes short, thin, toe IV (FTL 8.7 mm) longer than third of distance from base of tarsus to tip of toe IV (TFOL 27.3 mm). (22) Relative length of toes, shortest to longest: I <II <V <III <IV. (23) Tips of toes rounded, slightly enlarged, without grooves. (24) Webbing small: I 1 – 2 II 1 – 2 ½ III 1 – 3 ½ IV 3 ½ – 2 V (MTTF 4.3 mm; MTFF 1.8 mm; TFTF 10.4 mm; FFTF 9.6 mm). (25) Dermal fringe present along the entire length of toe V (26) Subarticular tubercles absent, but callous ridges beneath all toes present. (27) Inner metatarsal tubercle long, distinct, its length (IMT 3.0 mm) is 0.9 times the length of toe I (ITL 3.4 mm). (28) Tarsal fold absent. (29) Outer metatarsal tubercle absent; supernumerary tubercles and tarsal tubercle absent.

Skin: (30) Dorsal and lateral parts of head and body: snout, between eyes, side of head, back and flank covered with fine ridges forming reticulum. (31) Dorsal parts of limbs: covered with longitudinal folds. (32) Ventral parts of head, body and limbs: covered with dense, small glandular warts, coarser on throat. (33) Macroglands: pectoral glands small, rounded, on side of chest, posterior to arm insertion; small white femoral gland, on posterior shank, closer to knee than to vent.

Coloration in alcohol. (34) Dorsal and lateral parts of head and body: brown with irregular distinct darker markings; loreal region lighter brown with dark bands; a dark spot on canthus near nostril; tympanic region brown with a dark line under tympanic fold; upper lip continuous to canthal and tympanic region. (35) Dorsal parts of limbs: brown with dark brown narrow bands; posterior part of thigh light brown with reduced white spotting. (36) Ventral parts of head, body and limbs: throat, margin of throat and chest light brown; belly brown with white spots; webbing dark brown.

Coloration in life. (37) Dorsum and head greyish-brown getting lighter on flanks; temporal region dark greyish-brown; sides of head and body with brownish shine, indistinct in natural light, but quite visible in artificial light; upper and lower lip whitish; upper side of forearms and legs grey with darker transversal bands; ventral surface of belly and legs dark purple with small white spots on glandular warts. Iris entirely greyish-blue with vertical black pupil.

Male secondary sexual characters. (38) Vocal sacs: not distinct externally; openings as small slits, positioned near the proximal part of the tongue, surrounded by skin folds. (39) Nuptial spines absent.

Ecology and behaviour. The species was observed on 21, 22 and 26 May 2009 after sundown (1830 to 2000 hours). The weather was cloudy and it was raining heavily during the study period. On the first and second day, the frogs were heard calling upstream, approximately 150 m from the road, but on the third visit, after very heavy rainfall, the frog's calls were heard further downstream only. It is possible that the frogs had moved downstream with the force of the water or because suitable microhabitats were no longer available.

The frogs were passive and allowed themselves to be picked up without a struggle. They sat in a crouch. When disturbed or agitated, they moved or rather crawled laboriously. Three separate specimens were found and photographed. One of these specimens was collected on 22 May and is described here as the holophoront.

Vocalisation. The loud call of the male is a croaking “ kek-kek-kek-kek ”. The frogs continued calling at night when in the bag.

Figures

FIGURE 1. Images of Leptobrachium bompu in life. a. Dorso-lateral view, b. Dorsal view, c. Ventro-lateral view.

FIGURE 2. Images of Leptobrachium bompu holophoront, KA 0001 / 200905. a. Dorso-lateral view; b. Dorsal view; c. Ventral view.