Pelophryne murudensis, Das, 2008

Das, Indraneil, 2008, Two New Species Of Pelophryne (Anura: Bufoidae) From Gunung Murud, Sarawak (Northwestern Borneo), Raffles Bulletin of Zoology 56 (2), pp. 435-443 : 436-439

Pelophryne murudensis new species

( Figs. 1–2 )

Material examined. – Holotype: ZRC 1.11902 (ex-ID 7833) from Summit Trail to Gunung Murud, ca. 0.3 km from Reked Maligan (Church Camp) (03°54'53.8"N 115°30"11.5"E; 2,120 m a.s.l.) towards Kebun Batu, Sarawak, East Malaysia ( northwestern Borneo ), collector, I. Das, 4 May.2003.

Paratypes: ZRC 1.11903 –1.11905 (ex-ID 7737; 7839–40); three paratopotypes; other data as for holotype, except collection dates are 4 May.2003, 8 May.2003 and 6 May.2003, respectively . Additional material examined – SM D.a.3.1.1 (three specimens), Gunung Murud, Sarawak, Malaysia, collected by Eric Georg Mjöberg in 1922. Type locality is indicated in Fig. 5 .

Diagnosis. – A large (SVL to 25.6 mm in adult males) species of Pelophryne , diagnosable from congeneric species in showing the following combination of characters: head wider than long; snout oblique in profile; eye diameter less than snout length; tympanum exposed, over half diameter of eye; forehead lack pustulose tubercles; tubercles on dorsum not spinose and not surrounded by ring of asperities; digits swollen but not dilated; Finger I without a free phalange; webbing on Toe V to tip; subarticular tubercles distinct; mandibular spines and nuptial pads absent; cloacal opening around middle level of thighs; primary colour of dorsum brown, lacking an hour-glass pattern; dark throat spots present but no pale flank stripe and a dark U-shaped mark on venter.

Description of the holotype (adult male). – A large species of Pelophryne, SVL to 25.6 mm; habitus slender, with a relatively narrow waist ( Fig. 1 ); head much wider than long (HW/HL ratio 1.24), slightly depressed; snout squarish at the tip, when viewed dorsally, extending slightly beyond mandible, and oblique in lateral view; nares narrow-oval, wider horizontally, not elevated, laterally positioned, nearer tip of snout than to orbit of eye (E-N/E-S ratio 0.72); internarial distance less than distance from anterior margin of eye to nostril (IN/E-N ratio 0.76); eyes large (ED/HL ratio 0.43); eye diameter greater than eye to nostril distance (ED/E-N ratio 1.10); upper eyelids small; pineal ocellus not visible externally; interorbital width more than thrice upper eyelid width (IO/UE ratio 3.20); canthus rostralis distinct; loreal region slightly concave; maxillary teeth absent; a weak symphysial knob on anterior edge of mandible; mouth extending beyond posterior corner of eye; no rictal glands at posterior corner of mouth; weak tubercles on forehead; mandibular spines absent; asperities on gular region comprises obtuse tubercles; tongue oval, rather elongate, non-papillate, free posteriorly; choanae located close to antero-lateral edge of palate; vomerine ridge absent; vocal sac aperture located near angle of jaws; contracted pupil elliptical; tympanum visible, its annulus indistinct, oval, measuring 1.3 mm in horizontal diameter and 1.7 mm in vertical diameter, smaller than orbit of eye (ED/tympanum ratios 1.77 and 1.35, respectively); distance between eye and tympanum 0.7 mm, or 30.4% diameter of eye and 53.8% horizontal tympanum diameter; supratympanic fold absent; parotoid gland absent; subgular vocal sac, with paired openings; no supracloacal fold; postcloacal tubercles large, distinct; cloacal opening high relative to position of thighs; dorsum of body and limbs with large, rounded tubercles; tubercles largest in postocular region and on anterior portion of flanks; ventral surface of body tuberculate, most marked in abdominal region, where tubercles are flattened, rounded and in contact with each other.

Arm short and stout; fingers ( Fig. 2A ) short and stout, with extensive webbing; no free phalange projecting from web of Finger I; relative length of fingers: 3> 4> 2> 1; tips of finger weakly expanded, not dilated; width of tips of Finger III wider than those on other fingers; manus with fleshy webbing; outer aspect of Finger I, to base of swollen tip; inner and outer aspects of Fingers II–III and inner aspect of Finger IV, broadly to subarticular tubercle; dermal fringe along outer aspect of Finger IV extends to apical region; no nuptial pads or spines on fingers; subarticular tubercles present but indistinct, rounded, subequal on fingers and toes, numbering one on first and second fingers, and two on third and fourth fingers; palmar tubercles present; hind limbs slender and relatively short (TBL/SVL ratio 0.44), failing to meet when folded right angle to axis of body; toes ( Fig. 2B ) long; webbing on Toes I and II up to tip of disks, with no free phalanges; on toe III, to base of disks; on Toe IV and inner aspect of Toe V, to level of distal subarticular tubercle; on inner aspect of Toe I and outer aspect of Toe V, dermal fringe present to toe tips; relative length of toes: 4> 5> 3> 2> 1; toe tips expanded; subarticular tubercles rounded, numbering one on first, second and fourth toes, two on third and fifth toes; oval, inner and outer metatarsal tubercles; heel without a postaxial fold.

Colour. – In life, dorsum Fuscus (#21), or greyish-brown; a Dusky Brown (#19), or dark brown angular, interorbital bar in the form of a V-shaped mark, that is fused to a triangular mark of the same colour, narrow anteriorly, at the back of forehead; another dark triangular patch of the same colour at mid-dorsum, with its narrow edge anteriorly, forming a dark-brown hour-glass marking; a Dusky Brown (#19), or dark grey-brown preocular stripe extends from nostrils to eye, and continuing along postocular region, broadening after the level of tympanum, and continuing along flanks, sharply set off from the relatively lighter dorsum; lower flanks Cream Color (#54), or greyish-cream, with fine, scattered dark pigments; a pale subocular spot present; tympanum Buff (#124), or medium brown; tubercles on dorsum Scarlet (#14) in life, turning greyish-brown in preservative, paler apically; upper surfaces of limbs with Dusky Brown (#19), or dark-banded, with paler narrow intervening areas; throat and rest of venter Buff (#124), with Sepia (#219), or dark grey smudges, especially on throat and lower lips and a large (height 3.7 mm; width 5.8 mm) horse-shoe shaped mark of the same colour on abdominal region that is open posteriorly; pupil black and iris golden.

Measurements (in mm, holotype followed by the range, mean and SE in paratypes in parentheses). – SVL 21.9 (21.9–25.6, mean 23.5 ± 0.78); HL 5.4 (5.2–6.1, mean 5.53 ± 0.20); HW 6.7 (6.2–7.2, mean 6.67 ± 0.20); HD 4.1 (4.1–4.2, mean 4.13 ± 0.03); BW 7.1 (6.8–8.8, mean 7.85 ± 0.52); TBL 9.7 (9.3–9.8, mean 9.58 ± 0.11); ED 2.3 (2.3–2.7, mean 2.40 ± 0.10); UE 1.5 (1.5–2.1, mean 1.80 ± 0.12); IN 1.6 (1.6–2.2, mean 2.03 ± 0.14); IO 4.8 (3.9–4.8, mean 4.35 ± 0.21); E-S 2.9 (2.3–3.0, mean 2.65 ± 0.18); E-N 2.1 (2.0–2.7, mean 2.23 ± 0.16) and A-G 10.3 (10.3–14.3, mean 12.18 ± 0.84). See also Table 1.

Etymology. – Latin for inhabitant of Gunung Murud.

Ecological notes. – Only males of this species are known, all collected from montane forests, from edges of forest trails. They were found calling from leaves, 5 cm to 2 m above substrate, between 1900–2200 h. Call is a continuous trill. Species found in sympatry include Leptobrachium montanum , Philautus petersi and P. mjobergi . Females of the species remain unknown. Dominant genera of trees within the montane vegetation habitat of the new species include Leptospermum , Podocarpus , Agathis , Dacrydium and Dacrycarpus , characterised by small, thick leaves and stems, reaching up to 20 m. The undergrowth includes the pitcher plants, Nepenthes murudensis and N. muluensis , and the terrestrial montane ferns Dipteris conjugata and Blechnum vestitum . The larval stages of the new Pelophryne remain unknown, and the species may breed in the pitchers of Nepenthes .

Comparisons. – In showing finger tips not wider than basal phalanges, Pelophryne murudensis differs from P. brevipes , P. guentheri , P. rhopophilius and P. signata . Its oblique (vs. vertical) snout differentiates it from P. albotaeniata . The lack of a free phalange on Finger I differentiates it from P. lighti . Finally, its distinct subarticular tubercles and absence of both mandibular spines and nuptial pads differentiate it from P. api and P. misera .

Distribution of character states of Pelophryne species as recognised at present are in Table 3.

Figures

Fig. 1. Holotype of Pelophryne murudensis, new species (ZRC 1.11902) in life.

Fig. 2. Left manus (2A) and pes (2B) of holotype of Pelophryne murudensis, new species (ZRC 1.11902). Scale bars = 2 mm.

Fig. 5. Map of Borneo, showing the location of Gunung Murud, the general type locality of Pelophryne murudensis, new species, and Pelophryne linanitensis, new species.