Austrochaperina aquilonia, ZWEIFEL, 2000

ZWEIFEL, RICHARD G., 2000, Partition Of The Australopapuan Microhylid Frog Genus Sphenophryne With Descriptions Of New Species, Bulletin of the American Museum of Natural History 2000 (253), pp. 1-130 : 12-13

Austrochaperina aquilonia , new species Figure 5

HOLOTYPE: AMNH A78186 , collected by Jared Diamond during July 3–8, 1966, in West Sepik Province, Papua New Guinea, on Mount Somoro , 9.5 km N, 10.5 km E of Lumi at an elevation between 730 and 1420 m.

PARATYPE: AMS R130405, collected by Tim Flannery on June 11, 1988, in West Sepik Province, Papua New Guinea, at Wilbeite Village, 3°25′S, 142°07′E (6.5 km N, 10 km E of Lumi, 800 m, on Papua New Guinea Topographic Survey 1:100,000 sheet no. 7391).

ETYMOLOGY: The specific name, a Latin adjective meaning ‘‘northern,’’ refers to its habitat in the north coast mountains.

DIAGNOSIS: The following combination of characters distinguishes this species: size moderate, males to 31 mm (no female specimens); toes unwebbed; hands small (HD/ SVL 0.22–0.23); finger discs small (3rd finger disc/SVL 0.021 –0.026), not or scarcely broader than penultimate phalanges; internarial span broad ( IN /SVL 0.111 –0.118) .

DESCRIPTION OF HOLOTYPE: Adult male (vocal slits present) with the following measurements and proportions (those of the paratype given in parentheses): SVL 31.0 (23.3), HW 11.2 (9.0), TL 12.7 (11.1), EY 3.4 (3.15), EN 2.3 (1.6), IN 3.45 (2.75), HD 7.1 (5.2), FT 13.6 (11.1), third finger disc 0.8 (penultimate phalanx 0.55) (0.6, phalanx 0.4), fourth toe disc 1.1 (0.6) (1.0, phalanx 0.5), TY 1.7 (1.9); HW/SVL 0.361 (0.386), TL/SVL 0.410 (0.476), EY/SVL 0.110 (0.135), IN/SVL 0.111 (0.118), EN/SVL 0.074 (0.069), EN/IN 0.667 (0.582), HD/ SVL 0.229 (0.223), FT/SVL 0.439 (0.476), FD/SVL 0.026 (0.021), TD/SVL 0.035 (0.043).

Body relatively slender, head as wide as body, snout bluntly pointed as seen from above, protruding slightly in lateral view; nares just visible from above; canthus rostralis evident but rounded, loreal region a steep, flat slope; eyelid slightly narrower than interorbit, tympanic ring scarcely visible. Relative lengths of fingers 3> 4> 2> 1, the first half the length of second, all with grooved terminal discs at most only slightly wider than penultimate phalanges, subarticular elevations low, rounded (fig. 55F). Relative lengths of toes 4> 3> 5> 2> 1, all with grooved terminal discs wider than the penultimate phalanges, that of the fourth toe broadest. Subarticular elevations low, round- ed, the inner metatarsal elevation elongate, rounded (fig. 55F). Dorsal skin surface slightly granular; a faint, curved, postorbitalsupratympanic fold.

The dorsal ground color is pale gray-brown, dominated by darker brown irregular spotting and mottling. On the limbs the pattern has more the appearance of pale spotting on a dark ground. The snout and face are dark brown with a faint lighter pattern on the upper lips. The anterior and posterior surfaces of the thighs are mottled; the palms and soles are essentially unmarked. The chin and chest are brown with coarse white spotting and mottling; the abdomen is pale with faint indication of darker patterning. The undersides of the hind limbs are pale with a slight darker pattern.

VARIATION IN TYPE SERIES: The paratype is an adult male (vocal slits present) whose measurements and proportions are noted above. In color and pattern it closely resembles the holotype except that the patterning is even less distinct.

ILLUSTRATIONS: Hands and feet, fig. 55F.

CALL: The call is unknown.

COMPARISONS WITH OTHER SPECIES: Only two other species of Austrochaperina are known from the Torricelli Mountains, A. basipalmata and A. adamantina . Basally webbed toes, narrower internarial distance, and broader finger discs distinguish basipalmata from aquilonia . Austrochaperina aquilonia and A. adamantina are similar in most respects but differ strikingly in the larger finger discs of the latter (fig. 55). This does not appear to result from difference in the state of preservation, as the two aquilonia , with smaller discs, are well preserved. Confirmation of other possible differences in proportions must await additional specimens.

HABITAT AND HABITS: Nothing is on record.

DISTRIBUTION: Known only from the type and paratype localities, about 3 km apart in the Torricelli Mountains of north-coastal Papua New Guinea (fig. 7).

Figures

Fig. 5. Holotype of Austrochaperina aquilonia, AMNH A78186, SVL 31.0 mm.