Rana rufipes, Inger & Stuart & Iskandar, 2009

Inger, Robert F., Stuart, Bryan L. & Iskandar, Djoko T., 2009, Systematics of a widespread Southeast Asian frog, Rana chalconota (Amphibia: Anura: Ranidae), Zoological Journal of the Linnean Society 155 (1), pp. 123-147 : 137-138

RANA RUFIPES SP. NOV.

(Previously referred to as Padang Large morphotype)

Rana cf. chalconota Inger & Iskandar, 2005: 138 ; Stuart et al., 2006: 473.

Holotype

FMNH 268580 (field no. 15864), an adult female from Limau Manis, 373 m (0°54′S / 100°28′E), Padang , West Sumatra, Indonesia. Collected in a disturbed forest 7.vii.2001, by Djong Hon-Tjong and David Gusman.

Paratypes

FMNH 268572 , 268578-79 , two adult females and one juvenile collected at same site and elevation as holotype on 3.vii. and 7.vii.2001 ; FMNH 268573-77 , 268581-83 , four adult males, four adult females from same locality as holotype, but at 405 m on 4.vii. and 10–11.vii.2001 ; FMNH 268584 , 268587-88 two adult males, one adult female from Padang Jernih (0°52′S / 100°28′E) 255–340 m, Padang , West Sumatra, 26.vii.2001 ; FMNH 268585-86 , one adult male, one juvenile from Sikayan Ubi (0°53′S / 100°27′E) 292 m, Padang , West Sumatra, 23.vii.2001 . All with same collectors as holotype.

Etymology

Specific name from rufus, L., meaning reddish, and pes, L., meaning foot, referring to the reddish tinge on the underside of the webbing in life.

Diagnosis

A large form of the Rana chalconota group, adult females 46–64 mm SVL, males with nuptial pads 44–48 mm. Dark spots present on back. Nuptial pad of males not constricted. Humeral gland of males visible only by dissection. Tympanum relatively small, TYM/ SVL of females usually <0.068, of males usually <0.106.

Description

Habitus moderately slender, head slightly wider than trunk, legs long. Head triangular, slightly longer than broad; snout obtusely pointed, projecting slightly beyond lower jaw, longer than diameter of eye; nostril on side of snout, closer to tip of snout than to eye; canthus angular, not constricted; lores vertical, concave; interorbital wider than upper eyelid and wider than internarial; pineal body faintly visible between anterior corners of upper eyelids; tympanum distinct, about diameter of eye in females, slightly larger in males, inner portion slightly depressed; vomerine teeth in short, oblique groups, distance between groups equal to distance from choanae.

Fingers long, length of third finger equal to distance from rear of eye to nostril; without webbing; second and third fingers with narrow, movable fold of skin on medial margins; tips of three outer fingers with wide discs, that of third finger three-quarters or more the diameter of the tympanum in females, disc of first finger about half width of disc of second finger, all discs with circummarginal grooves; subarticular tubercles conspicuous; bases of third and fourth fingers with one or two supernumerary tubercles, base of second finger with one; finger lengths 3> 4> 2> 1. Tips of toes expanded into discs smaller than those of fingers, but with circummarginal grooves; webbing extensive, to base of discs on lateral margins of first three toes and on medial margin of fifth, medial edge of fourth toe fully webbed to just beyond the distal subarticular tubercle; narrow dermal ridge along medial edge of distal joint of first toe and along lateral edge of distal joint of fifth toe; a low, oval inner metatarsal tubercle, shorter than distance to subarticular tubercle of first toe; a distinct, round outer metatarsal tubercle.

Skin of back granular in females, in males granules tipped with colourless asperities or spinules; similar spinules present on lores in some males, the variation probably an artefact of preservation; a distinct, low dorsolateral fold; rear of abdomen rugose, rest of venter smooth.

Males with paired vocal sac openings on floor of mouth. Whitish, velvety nuptial pad on dorsal and medial surfaces of first finger, not constricted. The humeral gland is detectable only by cutting and folding back the skin of the upper arm.

Colour in preservative medium brown dorsally and on sides; side of head dark brown, upper lip white; dorsal surfaces with small dark spots; ventral surfaces of body whitish, unmarked; dark crossbars visible on hind limb only in a few individuals; ventral surface of webbing reddish, the colour fading in preservative.

Measurements (mm) of holotype: SVL 62.0, tibia 34.3, head width 18.9, head length 23.2, tympanum diameter 4.8, width of disc of third finger 4.1.

Variation

Females 53.8–64.4 mm, mean 60.58 ± 1.55 mm (N = 6); males 43.7–48.4 mm, mean 45.36 ± 0.51 mm (N = 8). In the following data on body proportions, N = 7 for both sexes. T / SVL 0.537 –0.591, median 0.560 (N = 12), HW/ SVL of females 0.267 –0.312, of males 0.287 –0.309, HL/ SVL of females 0.360 –0.397, of males 0.370 –0.389, TYM/ SVL of females 0.065 –0.077, of males 0.097 –0.108; DF3/ SVL 0.053 –0.072, median 0.062 (N = 11).

Comparisons

Rana rufipes differs conspicuously from the form with which it co-occurs in West Sumatra, R. parvaccola (see below), in size, coloration of the webbing ( Inger & Iskandar, 2005), relative size of the tympanum ( TYM / SVL) and width of the disc of the third finger ( DF 3/ SVL) (see Tables 2 and 6). The uncorrected pairwise sequence divergence between R. rufipes and the cooccurring R. parvaccola (see below) is 14.75–14.93% (Table 4).

Rana rufipes is one of the largest members of this species group, with males larger than those of any other form and females larger than those of any other except the Javan species ( Tables 2 and 6). This new species has the relatively smallest tympanum in the group, differing from all except males of R. labialis in TYM/SVL ( Tables 2 and 6). It is also the only member of the group in which the ventral surface of the webbing is reddish.