Megophrys parallela, Inger & Iskandar, 2005

Inger, Robert F. & Iskandar, Djoko T., 2005, A Collection Of Amphibians From West Sumatra, With Description Of A New Species Of Megophrys (Amphibia: Anura), Raffles Bulletin of Zoology 53 (1), pp. 133-142 : 134-137

Megophrys parallela , new species

( Figs. 1 , 2 )

Material examined. – Holotype, MZB (field number D33), adult male from Batang Sarasah, Lubuk Selasih, near Solok , West Sumatra (0 59’S / 100 38’E, 1289 m ASL), coll. Djong Hon-Tjong & David Gusman, 2-9 Sep.2001.

Paratypes – MZB (field numbers D48, K95), FMNH 264511-13 , all males, same data as holotype .

Diagnosis. – A small Megophrys , males less than 50 mm SVL; tympanum visible as a half circle; vomerine teeth present; a single dorsolateral fold, parallel to contralateral fold throughout its length, the folds not diverging anteriorly; no V-shaped fold from behind the eye to the shoulder (the parietoscapular fold).

Description. – A small-sized species of Megophrys , known males 40-48 mm SVL; habitus stocky, robust, head wider than trunk; snout short, pointed at tip, projecting beyond lower jaw; no dermal rostral projection; canthus rostralis sharp, angular, slightly constricted; lores slightly sloping, concave; nostril about equidistant between eye and tip of snout; diameter of eye subequal to length of snout; upper eyelid with short, narrow-based projection; eyelid with several low, conical tubercles; width of upper eyelid less than width of interorbital; tympanum small, posterior half obscured by skin; vomerine teeth present in short ridges between and slightly behind choanae; tongue notched at rear, no papilla.

Tips of digits rounded, not enlarged; first finger slightly longer than or equal to length of second; fourth subequal to second, third longest; subarticular tubercles of fingers indistinct; large palmar tubercle extending out from base of first finger. Hind limbs moderate, tibia less than 0.5 of SVL; toes with webbing at bases only, no fringes extending out towards tips; toe lengths 4>3>5>2>1; subarticular tubercles indistinct; inner metatarsal tubercle low, oval, as long as or longer than first toe; no outer metatarsal tubercle.

Dorsal skin smooth anteriorly, with low tubercles and short ridges posteriorly; a sharply angular supratympanic fold; a single dorsolateral fold parallel to contralateral fold, folds not diverging anteriorly and not reaching supratympanic fold; no V-shaped parietoscapular fold over rear of head and shoulders; sides with rounded tubercles; calf with narrow raised, transverse ridges; ventral surfaces granular.

Color in preservative dark gray or brown dorsally; a dark triangular interorbital marking, apex to rear; laterally tip of snout dark brown, a dark bar below eye; sides of trunk unmarked; chin, throat and chest dark brown; abdomen cream colored with varying amounts of brown mottling; forearm with dark crossbars; calf with narrow dark crossbars.

Males have velvety, dark brown nuptial pads on the first and second fingers on the dorsomedial surface from the base of the fingers to the beginning of the terminal joint.

Measurements (mm) of holotype: SVL 47.6, T 21.5, HW 22.8, HL 19.4, eye diameter 6.8, snout 6.7. Measurements and body proportions of type series given in Table 2

Etymology. – Specific name from parallelus (Latin) meaning parallel, referring to the condition of the longitudinal skin folds.

Habitat notes. – One frog was caught in primary forest, the remainder in secondary forest. All were found between 1289 and 1320 m ASL. Two were on dead leaves and one on a small log on the banks of a small (width 5 m) stream. We have no information on the perch position of the other three. Comparisons. – This Sumatran species appears to be most similar to M. aceras Boulenger , but is distinctly smaller than mainland M. aceras (Table 2). In M. aceras the dorsolateral folds diverge sharply anteriorly and usually reach the supratympanic folds, the pattern illustrated by Boulenger (1903); in M. parallela these folds do not diverge anteriorly and do not reach the supratympanic folds. The illustration of the type of M. aceras also shows a V-shaped ridge from the parietal region ending at the shoulders; this character is present in all the M. aceras we have seen, but is absent in M. parallela . The head of the Sumatran form is wider and longer and the tympanum smaller (Mann-Whitney test, P<0.01) than in M. aceras (Table 2).

Among the other small (males <65 mm) species of Megophrys from Indochina through Sundaland, M. longipes Boulenger and M. parva (Boulenger) differ from M. parallela in having longer legs and smaller heads (Table 2), in having the dorsolateral folds diverging anteriorly, and in having distinct parietoscapular folds (Table 3). Megophrys minor Stejneger also differs from M. parallela in having a distinct parietoscapular fold and a smaller head and lacks vomerine teeth (Tables 2, 3). Megophrys palpebralespinosa Bourret differs from parallela in lacking vomerine teeth and in the orientation of the body folds (Table 3) and its smaller head (Table 2). Megophrys dringi Inger, Stuebing & Tan differs from M. parallela in lacking vomerine teeth and in having a distinct parietoscapular fold, relatively longer legs and narrower head (Table 2). Megophrys edwardinae Inger differs from M. parallela in lacking vomerine teeth, in having much rougher skin with scattered short ridges and prominent tubercles dorsally, and the snout distinctly shorter than the eye diameter. Megophrys baluensis (Boulenger) differs from M. parallela in having two longitudinal folds on the trunk, the snout not projecting beyond the mandible, and related to the last, a shorter head.

In other species of Megophrys from Southeast Asia, males usually exceed 65 mm SVL and differ from the Sumatran form in other ways, e.g., presence of a rostral projection [ M. nasuta (Schlegel) ], broad-based palpebral projection ( M. nasuta , M. kobayashii Malkmus & Matsui ), a dark stripe on side of head ( M. lateralis Anderson ), toes with dermal fringes and no vomerine teeth ( M. auralensis Ohler, Swan & Daltry ).

Comparative material. – Megophrys aceras : Peninsular Malaysia: ZRC 1.6052 (Perlis State) ; FMNH 185897-98 (Selangor State) . Thailand: FMNH 135344 (Nakhon Si Thammarat Prov.) , FMNH 216092-95 , USNM 94795-96 (Trang Prov.) . Megophrys boettgeri : China: FMNH 24397 , 24399 , 24400 , 24402 (Fujian Prov.) . Megophrys brachykolos : Hong Kong: FMNH 69064-65 , 109979 , 109981 , 256939-40 . Megophrys longipes : Peninsular Malaysia : FMNH 185899 (Selangor State) , BPBM 17248 , FMNH 216240 , ZRC 1.3460 a, 1.8377 (Pahang State) . Megophrys montana : Java: ZRC 1.6411 , 1.6414 , 1.6422 , 1.6425 (West Java, Sukabumi ) . Megophrys minor : China: FMNH 49523 , 167973 (Sichuan Prov.) . Megophrys omeimontis : China: FMNH 232870 , 232874-75 , 232877 (Sichuan Prov.) . Megophrys palpebralespinosa : Laos: FMNH 258098-258100 (Phongsaly Prov.) . Vietnam: FMNH 254036 ( Vinh Phy Prov. ) . Megophrys parva : Laos: FMNH 255543 ( Huaphahn Prov. ) . Thailand: FMNH 175915-16 , 175918-20 (Chiang Mai Prov.) ; FMNH 216096 ( Surathani Prov. ) ; ZRC 1.8489 - 92 (Phuket Prov.) .

Figures

Fig. 1. Dorsal view of Megophrys parallela, new species (Paratype: FMNH 264512). Scale bar = 10 mm.

Fig. 2. Lateral view of head of Megophrys parallela, new species (Paratype FMNH 264512). Scale bar = 5 mm.