Cophixalus tomaiodactylus, Kraus, Fred & Allison, Allen, 2009

Kraus, Fred & Allison, Allen, 2009, New species of Cophixalus (Anura: Microhylidae) from Papua New Guinea, Zootaxa 2128, pp. 1-38 : 31-35

Cophixalus tomaiodactylus , sp. nov.

Fig. 2 E, F

Holotype. BPBM 26185 (field tag AA 17493), adult male, collected by A. Allison at Kamiali Wildlife Management Area, 2.6 km N and 9.3 km W of Cape Dinga, 7.28188171ºS, 147.065022341ºE, 900 m, Morobe Province, Papua New Guinea, 31 March 2005.

Paratypes (n = 16). BPBM 26183–84, same data as holotype; BPBM 26182, same data as holotype except collected 30 March; BPBM 26186–88, same data as holotype except collected 1 April; BPBM 26189, same data as holotype except collected 3 April; BPBM 26190–91, same data as holotype except collected 2 April; BPBM 26192, same data as holotype except collected 4 April; BPBM 26195, same data as holotype except collected 5 April; BPBM 23720, Biaru Road, 4.2 km N, 4.3 km E of Nako airstrip, 7.6333722ºS, 146.8004583ºE, Morobe Province, Papua New Guinea collected 19 September 1987; BPBM 23731–33, 23948, same data as BPBM 23720 but collected 20 September 1987. The Biaru Road localities use the WGS 84 datum.

Diagnosis. A small species (male SV = 13.2–16.1 mm, female SV = 14.2–16.6 mm) with finger discs smaller than toe discs (3rdF/4thT = 0.67–0.84); first finger reduced in size, of recognizable form, lacking a disc with circum-marginal groove; finger discs narrow (3rdF/SV = 0.022–0.035); first toe reduced in size, lacking a disc with circum-marginal groove; dorsum with a dorsolateral row of pustules on each side, otherwise smooth; dark subocular blotch; dorsum light brown with scattered dark blotches laterally and dorsolaterally, but not forming a continuous band; and a rapid peeping call.

Comparisons with other species. The new species differs from all other Papuan Cophixalus except C. bewaniensis , C. desticans , C. humicola , C. iovaorum , C. kethuk , C. pipilans , C. shellyi , C. sisyphus , and C. tridactylus in having the combination of a reduced first finger and the finger discs distinctly smaller than the toe discs. From C. bewaniensis , C. humicola , and C. tridactylus the new species differs in still retaining a recognizable first finger instead of a nub. From the remaining species, C. tomaiodactylus differs in having the first toe lacking a disc and circum-marginal groove; all the other species have a distinct disc and groove on the first toe, except for C. iovaorum , which has the disc but no groove. Superficially, C. tomaiodactylus appears most similar to C. linnaeus and C. phaeobalius but is easily distinguished from both in its reduced first toe lacking a disc and by its much more rapid peeping call.

Description of holotype. An adult male with left-lateral incision, vocal slits. Head moderately wide (HW/ SV = 0.44), with oblique loreal region; canthus rostralis gently rounded, straight when viewed from above; nostrils directed laterally, closer to tip of snout than to eyes; internarial distance much larger than distance from naris to eye (EN/IN = 0.63, IN/SV = 0.11, EN/SV = 0.067); snout truncate, with slight dorsal protuberance, when viewed from the side, shallowly angulate when viewed from above; eyes moderately large (EY/SV = 0.13); eyelid 2/3 width of interorbital distance; tympanum very small (TY/SV = 0.034), with a clear, raised annulus. Dorsal surface slightly rugose, lateral surface smooth; supratympanic fold absent. Ventral surfaces generally smooth but weakly granular on abdomen. Fingers unwebbed, bearing discs with terminal grooves on F2–F4; relative lengths 3>4>2>1; first finger reduced in size, disc absent. Finger discs slightly wider than penultimate phalanges. Subarticular and metacarpal tubercles not obvious. Toes unwebbed, bearing discs with terminal grooves on T2–T5; relative lengths 4>3>5>2>1. Toe discs larger than those of fingers (3rd F/4thT = 0.72); disc of fourth toe approximately 1.5 times width of penultimate phalanx. Subarticular tubercles not obvious; inner metatarsal tubercle narrow, elongate, and barely developed; outer lacking. Hind legs rather short (TL/SV = 0.44).

Province, Papua New Guinea. BPBM 23720 was recorded from 2200 m on the Biaru Road on the west side of the

Bowutu Mts. on 19 September 1987; the other three individuals were recorded from the Kamiali Wildlife Management

Area, 900 m, Morobe Province, Papua New Guinea on the eastern versant of the Bowutu Mts. BPBM 26182 was

recorded on 30 March 2005; BPBM 26183 and 26185 were recorded on 31 March 2005.

Mean Mean

Call Note Internote Repetition Dominant Temp Total Duration Duration Duration Rate Frequency to be continued.

Mean Mean

Call Note Internote Repetition Dominant Temp Total Duration Duration Duration Rate Frequency

Specimen Call No. Time °C Notes s s s notes/s Hz

" N " " 11 1.99 0.1173 0.0699 5.3 4780

BPBM 26185 A 1832 " 8 1.37 0.1186 0.0601 5.5 5120

" B " " 9 1.50 0.1129 0.0680 5.7 5120

" C " " 8 INTERFERENCE 5250

" D " " 8 1.44 0.1270 0.0605 5.6 5210

" E " " 8 1.34 0.1173 0.0573 5.6 5250

" F " " 10 1.61 0.1108 0.0561 5.9 5160

" G " " 12 1.92 0.1038 0.0611 6.0 5120

" H " " 11 1.82 0.1162 0.0538 5.8 5080

" I " " 12 1.97 0.1117 0.0575 5.8 5130

" J " " 9 1.48 0.1070 0.0644 5.8 5030

" K " " 13 2.05 0.0989 0.0639 6.1 5030

" L " " 11 1.85 0.1069 0.0674 5.7 4950

" M " " 13 2.10 0.0994 0.0674 6.0 5110

" N " " 13 2.14 0.1031 0.0663 5.9 4950

" O " " 11 1.89 0.1116 0.0660 5.6 5120

" P " " 12 2.02 0.1068 0.0668 5.7 5250

" Q " " 12 2.05 0.1081 0.0680 5.6 5210

" R " " 11 1.87 0.1095 0.0666 5.6 5160

" S " " 12 2.03 0.1075 0.0672 5.7 5210

" T " " 11 1.89 0.1107 0.0669 5.6 5160

" U " " 12 2.02 0.1074 0.0664 5.7 5250

Color pattern gives overall impression of a dark brown frog with scattered darker-brown flecks. Dorsal ground color light straw, heavily stippled with brown, these densest mid-dorsally, lighter dorsolaterally and laterally. Sides with several irregular dark-brown blotches extending from behind eye to mid-body. Small dark-brown specks line the lighter dorsolateral region. Two dark-brown inguinal spots followed posteriorly by two smaller paravertebral spots. Snout tip dark brown; dark-brown subocular blotch continues posteroventrally to forearm insertion. Obscure dark-brown interocular bar. Rear of thighs light straw proximally, brown flecked with pale straw distally. Venter dark brown flecked with pale straw on abdomen and under thighs, with fewer pale flecks on chin and throat. Narrow, ill-defined pale-straw lines extend from each forearm to meet mid-ventrally, where joined with a similar line arising at mandibular symphysis. Iris black.

Measurements (in mm). SV = 14.9, TL= 6.5, HW = 5.8, HL = 4.5, IN = 1.6, EN = 1.0, SN = 1.8, EY = 2.0, TY = 0.5, 3rd F = 0.44, 4th T = 0.61.

Variation. Mensural variation for the type series is shown in Table 13. Dorsal ground color varies from lighter brown to medium brown. The dark-brown flecking and blotching varies in intensity, but all frogs are nondescript with irregular dark markings. Venters vary from lighter and more clearly flecked with pale straw than seen in the holotype to more uniformly brown. Rear of thighs is generally dark brown flecked with pale straw.

Color in life. Holotype (BPBM 26185): “Dorsum brown; light tan bar between eyes; light reddish dorsolateral line; flanks light tan, with irregular black blotches just posterior to front leg and with a broken black blotch just above groin, lateral to the dorso-lateral line. Venter: chin and throat black; pectoral area with black and white specks and slight bluish tinge; rest of venter gray, tinged with brown; iris bronze.”

Call. We recorded 57 calls from four individuals ( Table 14). All individuals were amongst clumps of moss at the base of trees, sometimes calling from the open and sometimes from within holes or crevices within the moss. One (BPBM 23720) was calling from a hole within moss encrusting a tree trunk about 50 cm above the forest floor. The species is highly crepuscular, with most calling activity taking place within an hour of dawn or within the first hour or so after dusk.

The call consists of a series of 2–13 rapidly delivered peeps with a mean repetition rate 5.4 notes/s (range 2.3–6.1). The mean note duration was 0.1070 s (range 0.0078–0.2210), and the internote duration averaged 0.0763 s (range 0.0170–0.4669). The first note often begins at low amplitude and gradually builds in amplitude toward termination ( Fig. 15 A). Subsequent notes exhibit incipient pulsing, rapidly reaching maximum amplitude, decreasing sharply, and then building up to about 75% of maximum amplitude before termination. The dominant frequency is 4710 Hz (range 3960–5250) ( Fig. 15 B). The first note exhibits some frequency modulation; the frequency increases by about 100–120 Hz throughout ( Fig. 15 C). Subsequent call notes fluctuate slightly in frequency, beginning and ending about 100 Hz lower than the main part of the call note. These lower frequencies coincide with the incipient pulses at the beginning and ending of the call notes.

Etymology. The name is a latizined Greek compound adjective meaning “possessing abbreviated digits”, formed from “tomaios”, meaning “cut off”, and “dactylus”, meaning digit, in reference to the short first fingers and toes.

Range. Known from middle elevations in the north and south sides of the Bowutu Mts., Morobe Province, Papua New Guinea ( Fig. 4 ).

Ecological notes. Animals were found in mossy forest in close association with clumps of moss encrusting the bases of small trees. The species is abundant, occurring at a density of about 1 per 5m 2.

Figures

FIGURE 2. Photos in life of (A) holotype of Cophixalus melanops (BPBM 20198), (B) paratype of Cophixalus melanops (BPBM 20197), (C) holotype of Cophixalus linnaeus (BPBM 31836), (D) paratype of Cophixalus phaeobalius (BPBM 26194), (E) paratype of Cophixalus tomaiodactylus (BPBM 26182), and (F) holotype of Cophixalus tomaiodactylus (BPBM 26185).

FIGURE 4. Map showing known distributions for Cophixalus cupricarenus (inverted triangles), C. desticans (circles), C. iovaorum (triangle), C. melanops (star), and C. tomaiodactylus (squares). Filled symbols are type localities; open symbols are additional localities, as relevant.

FIGURE 15. (A) Waveform, (B) power spectrum, and (C) spectrogram of call “ O ” (see Table 13) of holotype of Cophixalus tomaiodactylus (BPBM 26185) recorded by A. Allison at “ Pine Tree Camp ”, Kamiali Wildlife Management Area, 2.6 km N and 9.3 km W of Cape Dinga, 7.28188171 ºS, 147.065022341 ºE, 900 m elevation, Morobe Province, Papua New Guinea, at 1832 h, 31 March 2005. Air temperature 21.8 ° C.