Austrochaperina derongo, 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 : 27-33

Austrochaperina derongo , new species Figures 12 , 32H

Sphenophryne macrorhyncha : Zweifel, 1956 (part, specimens from vicinity of Idenburg Riv- er, Irian Jaya).

HOLOTYPE: AMNH A82289 , collected on April 7, 1968 by Fred Parker at Derongo, 400 m, Western Province, Papua New Guinea.

PARATYPES: Papua New Guinea (collected by Fred Parker unless otherwise noted). Western Prov. : AMNH A82287 , A82288 , A82290 , A92794–92798 (C&S), A145507 (C&S), A157805–157819, MCZ A92510 , A132847–133016 , type locality, Apr. 5–7, 1969 ; MCZ A80992 , 81222 , 81223 , Wang-

4 Myola is plotted on the Efogi Quadrangle, Papua New Guinea 1:100,000 topographic map series sheet 8479, in Central Province at approximately 9°8′44̎S, 147°43′44̎E. The Myola Guest House where we collected is in Northern Province, 5.0 km E, 0.5 km S of the mapped position of the village of Myola.

bin, 1460 m, Dec. 22, 1969; QM J67253 , 67254 , collected by M. Cunningham, S. Richards, and A. Dennis, 5 km W Tabubil (5°18′S, 141°11′30̎E), 580 m, Nov. 18, 1994 ; QM J67252 , collected by Cunningham, Richards, and Dennis, 9 km S Tabubil , Nov. 4, 1994 ; AMNH A90400 , 90401 , MCZ A87511 , A133034 , Gigabip, 1520 m, Aug. 23–24, 1972 ; MCZ A133035 , Kavorabip, 1520 m, Aug. 25, 1972. Simbu Prov.: AMNH A79974 , MCZ A133032 , 133033 , Soliabedo , 550 m, Sept. 24, 1967 ; MCZ A132824 , Ining River at Soliabedo , 370 m, Sept. 24, 1967 ; AMS R133070 , collected by S. Donnellan at Haia village , 720 m, 145°00′E 6°42′S, June 12, 1984 ; AMS R133062–133069 , R133071–133079 , collected by S. Donnellan at Haia Bush Camp, 880 m, 145°01′S 6°40′E, June 17–18, 1984. Gulf Prov. : AMNH A79975 , A157843– 157845 , MCZ A132834–132840 , Weiana, 8 km S, 1 km E Soliabedo, 460 m, Sept. 28, 1967 ; MCZ A133023 , 133024 , A132828, Camp II, Pio River , 6.5 km S, 1 km E Soliabedo, 300 m, Sept. 27–29, 1967 ; MCZ A132829 , A133026–133029 , Camp III, Nimi River , 13.5 km S, 1 km E Soliabedo, 430 m, Sept. 29, 1967 ; MCZ A133017–133022 , between Camp II, 6.5 km S, 1 km E Soliabedo, and Weiana, 8 km S, 1 km E Soliabedo , 430– 730 m, Sept. 29, 1967 ; MCZ A132826 , 132827 , Bol and Nimi headwaters, 370–610 m, Sept. 30, 1967 ; MCZ A132841 , Uraru, 90 m, Oct. 2, 1967 ; MCZ A132831–132833 , Koni, Purari River , 80 m, Oct. 4, 1967 ; UPNG 2503 , collector not noted, Purari Riv- er, Powaia No. 1, Oct. 12, 1970. Southern Highlands Prov.: UPNG 6979 , collected by Roy Mackay, Nov. 1984 on Mt. Bosavi , 1200 m ; ZSM 109 /1999, collected by T. G. Schultze-Westrum, in Sept. 1966 at Didessa, north slope of Mt. Bosavi ; AMS R122166– 122169 , R122232 , R122235–122239 , collected by S. Donnellan at Namosado, 615′S, 14247′E ; AMS R122294 , R122295 , R122785 , collected by S. Donnellan at Magidobo. Indonesia: Irian Jaya: AMNH A49531–49533 , A49537 , A49538 , A49540– 49541 , A49572 , A49617–49619 , A49621– 49626 , A49656 , A49661 , collected by W. B. Richardson on the Indisch-Amerikanische Expeditie (Third Archbold Expedition to New Guinea), 5 km SW of Bernhard Camp, Idenburg River, 850 m, 5 in Apr. 1939 (approximately 139°14′E, 3°26′S; note that the Idenburg River has been renamed Taritatu River ) ; QM J67250 , MZB 3563 , collected by S. Richards and D. Iskandar on Apr. 9 and 13, 1998, respectively, at Wapoga Alpha Camp , 1100 m, 3°08.687′S, 136°34.423′E .

TYPE LOCALITY: Derongo is a village located approximately 29 km N, 4 km W of Ningerum and 12 km from the border with Irian Jaya.

ETYMOLOGY: The name of the village that was the provenance of many specimens is used as a noun in apposition.

DIAGNOSIS: A moderate-size species of Austrochaperina with maximum SVL of females and males being 42 and 37 mm, respectively, but some populations are evidently smaller—females to 36 and males to 33 mm. The dorsal ground color is brown in preservative, olive to reddish brown in life, sometimes with dark speckles. Diagnostic proportions include finger discs relatively small, mean FD/SVL Ṩ 0.031, EY/SVL Ṩ 0.101, and IN/SVL Ṩ 0.104.

DESCRIPTION OF HOLOTYPE: Adult female with the following measurements and proportions: SVL 35.6, HW 12.8, TL 15.2, EY 3.2, EN 2.7, IN 3.5, HD 7.9, FT 15.4, disc of third finger 0.9 (penultimate phalanx 0.6), disc of fourth toe 1.25 (0.55); HW/SVL 0.360, TL/SVL 0.427, EY/SVL 0.090, EN/

5 Earlier (Zweifel, 1956: 13), I gave this locality as 4 km, overlooking a footnote in Archbold et al. (1942: 239) that corrected several Expedition localities referred to Bernhard Camp.

SVL 0.076, IN/SVL 0.098, EN/IN 0.771, HD/SV 0.222, FT/SV 0.433, FD/SVL 0.025, TD/SVL 0.035.

Head narrower than body; snout subacute in dorsal view, more so when viewed laterally, strongly projecting; nostrils much closer to tip of snout than to eye, lateral, barely visible from above; canthus rostralis rounded, loreal region nearly vertical, shallowly concave. Eyes small, lateral, interorbital space more than twice width of upper eyelid. Tympanum obscure, about 2 mm diameter, about its own diameter from posterior corner of eye. Relative finger lengths 3> 4> 2> 1, first reaching to anterior edge of subarticular elevation of second; all with terminal discs, that of third finger twice width of penultimate phalanx, of first finger only slightly broader than penultimate phalanx; subarticular elevations low, rounded, and inconspicuous, inner and outer metacarpal elevations scarcely evident. Relative toe lengths 4> 3> 5> 2> 1, first toe short, reaching to base of subarticular elevation of second; all toes with terminal discs, that of fourth toe about twice width of penultimate phalanx and wid- er than disc of third finger; subarticular elevations low, rounded, and inconspicuous, inner metatarsal elevation low, no outer elevation. Body essentially smooth, with only a weak postocular fold passing diagonally from the eye over the upper edge of the tympanum toward the arm.

The dorsal ground color in preservative is gray-brown with inconspicuous darker speckles and a pale band extending a short distance behind the eye on the dorsal surface of the head. The paler ground color of the loreal region extends to the ear and is overlain with darker speckles on the loreal region and upper lip. The sides of the body, the groin, and anterior surfaces of the thighs also show a pale ground color with darker speckles, verging on mottling on the thighs. The upper surfaces of the limbs are colored and patterned like the dorsum of the body, but with the markings more clustered. The posterior surfaces of the thighs resemble the dorsum—brown with darker speckling in no particular pattern. The ventral surfaces are pale and unmarked except for faint melanic clusters on the shanks. The soles are brown with pale irregular markings.

VARIATION IN TYPE SERIES: Among specimens from Western, Simbu, and Gulf Provinces, the largest of ten adult males measures 36.9 mm SVL, the largest of 33 adult females 49.7 mm. Males in this series mature at about 32–33 mm SVL, for individuals both with and without vocal slits lie in this size range. Mature females may be as small as 31 mm SVL, but others as large as 35 mm have ova only slightly enlarged. In the series of 19 specimens from Irian Jaya there are five gravid females in the range of 33.0– 35.4 mm SVL, whereas a 28- mm specimen is immature. Five males 29.0 to 34.8 mm have vocal slits, and a 26.7-mm specimen does not. The specimens from Southern Highlands Province include six adult females 29.5 to 35.6 mm SV and one apparently maturing at 27.8 mm. Five males 25.6 to 32.6 mm have vocal slits. The four largest females (SVL 44.7–49.7 mm) are all from one locality, Gigabip in Western Province. Thus, there appears to be geographic variation in size at maturity and in maximum size.

Differences in proportions as well as in size are evident among the widely scattered samples of derongo (table 2). Regression data are in table 3.

Variations from the color pattern described for the holotype include: dorsum largely without dark speckles; no postocular pale band; chin and chest darker than abdomen; tip of snout pale, almost white, in both sexes. In life, the individual illustrated from Soliabedo (fig. 12) was light olive-drab dorsally and somewhat yellower bordering the abdomen. The iris was similar to the dorsal ground color (as seen in a color transparency). A specimen from Derongo (color transparency) was reddish brown dorsally with darker markings, the border of the abdomen creamy white, and the iris brownish gold. Color transparencies of two specimens from Irian Jaya show a light gray ground color in one, a darker gray in the other. Each has a darker scapular mark, and the darker individual has the eyelids and anterior of the head darker gray (fig. 31H).

Most males (and some females) have the tip of the snout much paler than the rest of the head.

ILLUSTRATIONS: 3rd finger terminal phalanx, fig. 71Q; 3rd finger disc, fig. 50; premaxilla, fig. 64H; sacral region, fig. 73D; vomer, fig. 65L; hand and foot, fig. 55B.

CALL: Stephen Richards recorded the call of this species at Wapoga Alpha Camp in Iri- an Jaya on April 9, 1998. The call is a series of brief, harsh, pulsed notes (table 5). Mr. Richards estimates that his recording lacks the first three notes of the call, so by extrapolation the complete call would have lasted about 13 sec and comprised of about 24 notes. Five notes average 0.075 sec in length (0.070 – 0.077) with an average of 13 pulses (12–15). A typical note (fig. 80A) begins with three brief pulses followed by several longer, louder ones gradually diminishing in duration and intensity. The note repetition rate is about 1.9/ sec, the dominant frequency being 2650 Hz (see also Vocalizations).

The frog called from beneath a leaf in a creekbed adjacent to a small stream beside a trickle of water (S. Richards, personal commun.). The voucher specimen is QM J67250; a copy of the recording is on AMNH Herpetology tape no. 284. A call by another specimen (MZB 3564) recorded at the same locality sounds the same but is masked by the noise of running water.

COMPARISONS WITH OTHER SPECIES: Austrochaperina derongo is much like archboldi, hooglandi , and guttata ; only the last, with its large size, large finger discs, and long legs (table 2) stands out much from derongo . Col- or pattern adequately distinguishes hooglandi , and most archboldi can be separated by their greater internarial span and larger eyes.

HABITAT AND HABITS: The association of a calling individual with water (see above) and the capture of other specimens in the same habitat (S. Richards, personal commun.) represent the only information on the habits and habitat of this species. Most of the localities in Papua New Guinea fall in areas mapped by Paijmans (1975) as ‘‘Medium Crowned Lowland Hill Forest.’’ The two highest sites (Wangbin, 1460 m; Mt. Bosavi, 1200 m) are within Lower Montane Forest zones. Archbold et al. (1942) described the region where the Irian Jaya specimens were taken as heavily mossed rainforest.

DISTRIBUTION: Most locality records for A. derongo are at moderate to low elevations along the southern flank of the central dividing range from just east of the Irian Jaya– Papua New Guinea border to the Purari River drainage in Gulf and Simbu provinces ; the Irian Jaya localities are north of the central ranges and nearly 200 km from the closest station in Papua New Guinea (fig. 13). The elevation range is 80–1460 m .

REMARKS: If I am correct in associating ‘‘ Sphenophryne sp. B ’’ of Mahony et al. ( 1992) with derongo (see Karyology), then this species is unique among the few Austrochaperina for which there are data in having the chromosome number 2N of 24 rather than 26.

There is one known instance of sympatry between A. derongo and A. rivularis based on specimens collected by S. Donnellan at Namosado, Southern Highlands Province, Papua New Guinea. Two adult male A. rivularis (AMS R122164, R122165) taken along with ten A. derongo (AMS R122166– 122169, R122232, R122235–122239) stand out for their relatively large size: one (SVL 37.7 mm) is larger than any of the 10 derongo (maximum is a 35.6 mm female) and the other, at 35.5 mm, is at the upper range of that series. In all proportions in which derongo and rivularis differ, the two large males resemble rivularis rather than derongo . Figures 14–16 illustrate the greater tibia length, eye size, and disc width of rivularis at the site of sympatry.

Variations in size and proportions among the geographically scattered samples of this species lead me to suspect that derongo may be a composite of two or more species. However, I am unable to subdivide the species to my satisfaction. More recordings of calls might resolve the question; the only recording at present is from the most remote part of the range.

Austrochaperina gracilipes Fry Figure 17

Austrochaperina gracilipes Fry, 1912: 93 (type locality, ‘‘ Somerset , Cape York, North Queensland,’’ Australia; holotype, AMS R4536 , collected by C. Hedley and A. R. McCulloch in October 1907).

S[phenophryne]. gracilipes : Nieden, 1926: 48 (first use of this combination).

Sphenophryne gracilipes : Parker, 1934: 155. Zweifel, 1962: 31; 1985b: 289.

Sphenophryne robusta : Zweifel, 1965: 2 (part, gracilipes considered a synonym).

DIAGNOSIS: A small Austrochaperina —females to almost 23 mm SVL, males to 20 mm —with well-developed digital discs, small eyes (EY/SVL <0.115), long legs (TL/SVL mean of 0.464), and a call consisting of a train of high-pitched peeps. No other known New Guinean Austrochaperina has this combination of characteristics.

MORPHOLOGY: Size small, less than 23 mm SVL. Head narrow, tapering to bluntly rounded snout, more pointed in profile, and overhanging the somewhat undershot lower jaw. Loreal region flat, nearly vertical; nostrils lateral, scarcely visible from above, about halfway between eye and snout tip but appearing closer to latter in profile. Eyes lateral, easily visible from below; eyelid slightly narrower than interorbital space. Tympanum inconspicuous, annulus one-half eye diameter or less. Relative lengths of fingers 3> 4> 2> 1, first less than half length of second; fingers 2–4 with grooved terminal discs slightly broader than penultimate phalanges, disc of first finger not broadened; subarticular and inner metacarpal elevations moderately prominent (fig. 57C). Toes unwebbed, relative lengths 4> 3> 5> 2> 1, first less than half length of second; grooved terminal discs of toes 2–5 broader than penultimate phalanges and larger than finger discs, disc on first toe small, not broader than penultimate phalanx; subarticular and inner metatarsal elevations moderately prominent (fig. 57C). Body smooth above and below; a weak, curved postocular-supratympanic fold.

COLOR AND PATTERN: The dorsal ground color in preservative is brown. A dark loreal streak often continues as an ill-defined dorsolateral streak separating the paler side of the body from the darker middorsal region. Small dark spots often are present on the dorsal and lateral ground color, and most individuals have a pale vertebral hairline. The upper surfaces of the limbs are tan with dark- er spots and speckles. The groin is paler, immaculate, or with indistinct darker flecks. Anterior and posterior surfaces of the thighs have a similarly pale ground color but are more heavily marked, comparable to the dorsal surfaces. The chin and chest are spotted to mottled with gray-brown on a tan ground, with the intensity of spotting being quite variable. The tip of the snout is gray. The abdomen is typically less heavily marked, whereas the undersides of the thighs are more like the chin and chest.

Living frogs from Wipim, Western Province (fig. 17), had the dorsum grayish to golden brown anteriorly, changing to reddish brown posteriorly and on the hind legs; a fairly distinct dark stripe on the canthus rostralis and through the ear, and a diffuse dark- er band dorsolaterally on the back; central area of the back somewhat darker than the sides; a fine vertebral hairline; remainder of the dorsal pattern mostly in the form of dark brown to black maculations on the ground color; undersides mottled with dark and light gray, mottling more intense on the chin and farther back on the ventral surfaces; and iris golden in the upper half, much darker reddish gold in the lower half. Australian frogs of this species have bright orange in the axilla and groin as well as on the hidden surfaces of the thighs and upper arm; no such color was present in the Papuan frogs. Australian specimens are illustrated in color in Cogger ( 1992) and Cameron and Cogger ( 1992).

VARIATION IN SIZE AND PROPORTIONS: The largest of about 100 specimens from Papua New Guinea is a female 22.8 mm SVL, and all eight frogs measuring more than 20 mm are females. Males reach 19.6 mm and are mature (calling) by at least 17.5 mm. Females are mature by at least 19.1 mm, probably smaller. Statistics for proportions are in table 2, and those for regressions in table 3. Minor average differences in some proportions between Australian and New Guinean samples do not appear to be significant (Zweifel, 1985b).

ILLUSTRATIONS: 3rd finger terminal phalanx, fig. 71J; premaxilla, fig. 64A; sacral region, fig. 72I; vomer, fig. 65I; hand and foot, fig. 57C.

CALL: ‘‘The call is a train of relatively high-pitched peeps (about 3700–4300 Hz) uttered over a period of about 10–29 seconds, each peep about 0.14–0.17 seconds in length.... the number of notes per minute ranges from 77 to 100 and the number of notes per call from 15 to 33.... a minute or more may elapse between calls’’ (Zweifel, 1985b: 291). The quoted description includes Papuan (fig. 77D) and Australian samples with a temperature range of 23.4–24.8°C. No geographic differentiation is evident.

COMPARISONS WITH OTHER SPECIES: This is a rather generalized species of Austrochaperina with no particularly distinguishing morphological features except its small size, but it differs from other New Guinean species in its call and lowland, seasonal habitat. No other known New Guinean Austrochaperina has a repetitive, peeping call (although several Cophixalus and Oreophryne do), and no other Austrochaperina is known from grassy or savanna habitats at low elevations.

Austrochaperina adelphe of Northern Territory, Australia, is identical in morphology to A. gracilipes but differs in the advertisement call. Curiously, whereas Australian and New Guinean gracilipes differ in that the former have bright orange pigmentation in the axilla and groin, adelphe and New Guinea gracilipes are alike in lacking this feature.

HABITAT AND HABITS: Where I collected A. gracilipes at Wipim, the frogs had climbed up blades of grass at night to call where the vegetation was grassy woodland with denser gallery forest along small streams. Other Papuan localities appear to be in similar vegetation. In Australia the species lives at similar sites but also evidently invades pockets of rainforest (Cameron and Cogger, 1992; Zweifel, 1985b).

Parker (1982) recorded gracilipes (as Sphenophryne robusta ) as the prey of a snake, Tropidonophis mairi (as Amphiesma mairi ).

DISTRIBUTION: Austrochaperina gracilipes is the only species of microhylid frog known to inhabit both Australia and New Guinea (fig. 7). In the former area it occurs on the Cape York Peninsula of Queensland. The known range in Papua New Guinea encompasses the non-rainforested lowlands of Western Province. It is likely that gracilipes occurs also in adjacent parts of Irian Jaya, although the species is not yet reported from there.

LOCALITY RECORDS AND SPECIMENS EXAMINED: See Zweifel (1985b: 292–293) for this information.

REMARKS: Austrochaperina gracilipes may be a junior synonym of Microbatrachus pusillus ; see the account of that questionable taxon.

Figures

Fig. 12. Austrochaperina derongo, MCZ A132824, SVL 41.9 mm, photo by Fred Parker.

Fig. 32. Holotype of Liophryne allisoni, AMNH A81221, SVL 21.9 mm.

Fig. 14. Comparison of tibia lengths in Austrochaperina derongo (circles) and A. rivularis (squares) from Southern Highlands Province, Papua New Guinea. For regression data, see table 3.

Fig. 17. Austrochaperina gracilipes, AMNH A83072, SVL 18.0 mm.