Cophixalus iovaorum, 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 : 9-11

Cophixalus iovaorum , sp. nov.

Fig. 1 D

Holotype. BPBM 19287 (field tag FK 8883), adult male, collected by F. Kraus at Siruohu, W slope Mt. Obree, 9.44467ºS, 148.00923ºE, 1560 m, Central Province, Papua New Guinea, 29 January 2004.

Paratypes (n = 30). BPBM 19273, same data as holotype except 1640–1680 m and collected 27 January 2004; BPBM 19274–86, same data as BPBM 19273 except collected 28 January 2004; BPBM 19288, same data as holotype; BPBM 19289, same data as BPBM 19273 except collected 29 January 2004; BPBM 19290–93, W of Siruohu, 9.4433876ºS, 148.0081743ºE, 1600 m, 29 January 2004; BPBM 19294, same data as BPBM 19273 except collected 30 January 2004; BPBM 19295–96, same data as BPBM 19273 except collected 2 February 2004; BPBM 19297–98, PNGNM 24052–56, slope W and below Siruohu, 9.4456521ºS, 148.0063578ºE, 1580–1640 m, 2 February 2004.

Diagnosis. A small species (male SV = 13.2–16.0 mm, female SV = 16.6–17.2 mm) with finger discs smaller than toe discs (3rdF/4thT = 0.52–0.65); first finger reduced in size, of recognizable form, lacking a disc; dorsum smooth, with narrow, dark hourglass marking on dorsolateral surface; side of face uniformly black; and call a series of up to 68 rapid peeps.

Comparisons with other species. The new species differs from all other Papuan Cophixalus except C. bewaniensis , C. humicola , C. kethuk , C. pipilans , C. shellyi , and C. tridactylus in having the combination of a reduced first finger lacking a disc with circum-marginal groove 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 C. pipilans , and C. shellyi the new species differs in having dark hourglass-shaped markings on the dorsolateral surface (dorsum uniform light brown in C. pipilans and C. shellyi ). The only other Cophixalus species having a dark hourglass pattern dorsally are C. kethuk and C. tetzlaffi . The former has basal webbing between the toes (absent in C. iovaorum ), white speckles on the face (uniformly black in C. iovaorum ) and the hourglass pattern is comprised of two wide dark lines (narrow lines in C. iovaorum ). Cophixalus tetzlaffi is larger (males to 23 mm SV) and has the finger discs wider than the toe discs.

Description of holotype. An adult male with small right-lateral incision, vocal slits. Head moderately wide (HW/SV = 0.37), with vertical loreal region; canthus rostralis rounded, straight when viewed from above; nostrils directed laterally, closer to tip of snout than to eyes; internarial distance considerably larger than distance from naris to eye (EN/IN = 0.61, IN/SV = 0.12, EN/SV = 0.076); snout angulate and slightly projecting when viewed from the side, rounded when viewed from above; eyes moderately large (EY/SV = 0.14); eyelid almost 2/3 width of interorbital distance; tympanum indistinct and small (TY/SV = 0.062), annulus more obvious anteriorly and ventrally than dorsally and posteriorly. Dorsal and lateral surfaces weakly granular, ventral surfaces smooth. Supratympanic fold absent. Fingers unwebbed, relative lengths 3>4>2>1; bearing discs on F2–F4, with terminal grooves on F3 and F4 but not on F2; first finger less than half as long as second, lacking disc and groove. Finger discs barely wider than penultimate phalanges. Subarticular tubercles not obvious; metacarpal tubercles weakly developed skin thickenings. Toes unwebbed, bearing discs with terminal grooves, except on T1; relative lengths 4>3>5>2>1. Toe discs considerably larger than those of fingers (3rd F/4thT = 0.54); disc of fourth toe approximately 1.5 times width of penultimate phalanx; disc of first toe same width as penultimate phalanx. Subarticular tubercles poorly developed; inner metatarsal tubercle narrow and elongate, outer lacking. Hind legs moderately long (TL/SV = 0.45).

Dorsum light gray-brown, vaguely clouded with darker brown, this especially distinct on top of head. Two broken, semi-circular, narrow dark-brown dorsolateral stripes extend from behind eyes to groin; beginning of each stripe widened ventrally into a postocular blotch. Sides light gray-brown with few dark brown flecks. Face uniform dark brown, margined above with silver-gray line extending from tip of snout, along canthus, and along eyelid margin. Venter pale straw heavily flecked with dark brown, more densely flecked on chin and throat and less so posteriorly. Rear of thighs light gray-brown with few dark-brown flecks; front and undersides of thighs like venter except that straw ground color appears in smaller and denser flecks. Darkbrown blotch below anus. Iris black with small silver flecks.

Measurements (in mm). SV = 14.5, TL= 6.5, HW = 5.3, HL = 4.8, IN = 1.8, EN = 1.1, SN = 2.0, EY = 2.0, TY = 0.9, 3rd F = 0.34, 4th T = 0.63.

Variation. Mensural variation for the type series is shown in Table 4 . Color-pattern elements are remarkably uniform. Dorsa are mostly light gray-brown, but a few are darker sepia and a few are brown with a slightly yellow cast. In one specimen the dorsolateral stripes broaden posteriorly and dissolve into a field of freckles. Venters differ only slightly in amount of dark-brown flecking, with those having the most showing less contrast in appearance between chin/throat and abdomen.

Color in life. BPBM 19273: “Dorsum tan with obscure darker tan flecks and scattered black flecks. One sinuous black suprascapular stripe and one black postocular stripe on each side. Venter gray mottled with black, except chin, which is black. Row of black spots on front of thigh. Iris tan. Face black.” BPBM 19274 had a dorsum more variegated with black; several specimens had a light stripe running along the canthus and margin of upper eyelid.

Call. Animals call from 1–2 hr before sunset until 1–2 hr after, with the frequency of calling animals decreasing noticeably soon after dark. They may call briefly during the daytime following rain. Animals call either from below leaf litter, perched on leaf litter, or perched on low-stature plants no higher than 15 cm above ground.

The call is a rapid series of raspy chirps. Call characteristics of the three individuals we recorded are shown in Table 5. The number of notes per call ranged from 1 to 68. The one-note call appears to be aberrant, perhaps representing a spacing chirp or an aborted call. If this call is excluded, together with an incomplete call (Uncaptured-A), the remaining seven calls ranged from 21–68 notes, with a mean of 47 notes. The duration of these calls averaged 14.71 s (range 6.23– 20.50 s). The mean interval between the notes, 0.2179 s (range 0.0561–0.3170) was more that twice the duration of the notes, which averaged 0.0958 s (range 0.0947–0.1041). The mean repetition rate was 3.2 notes/s (range 2.7–3.8). The internote interval tends to increase – i.e., for the repetition rate to decrease – towards the end of the call ( Fig. 8 ). The first note in the call tends to be about half the amplitude (volume) of subsequent notes. The duration and structure of the call notes were otherwise fairly similar during the course of the calls and between individuals. The second and subsequent call notes show a slight tendency towards pulsing, with the first ~130 ms of the call note having a higher amplitude than the rest of the call note ( Fig. 9 A). The dominant frequency of the calls averaged 5400 Hz (range 4990–5590) ( Fig. 9 B). There is also a marked tendency for the frequency of the call to increase by about 400 Hz from the beginning to the end of the call note ( Fig. 9 C).

Etymology. The name is a genitive honorific for Bulisa and Didibu Iova, who greatly and hospitably assisted our expedition to Mt. Obree.

Range. Known only from the western slope of Mt. Obree, Central Province, Papua New Guinea ( Fig. 4 ).

Ecological notes. Animals were typically fossorial and found to be common on hillsides in mid-elevation primary rainforest from 1540–1640 m, and it was the only frog commonly heard on the local ridgeline. The understory in this forest was not dense and contained considerable amounts of leaf litter.

Mean Mean

Call Note Internote Repetition Dominant Specimen Call Temp Total Duration Duration Duration Rate Frequency No. No. Time °C Notes s s s notes/s Hz BPBM 19287 A 1910 18.3 54 18.24 0.0952 0.2471 2.9 5340 " B " " 21 6.23 0.0963 0.2104 3.3 5510 " C " " 37 9.68 0.0949 0.1714 3.8 5510 BPBM 19288 A 1945 18.3 68 20.50 0.0907 0.2139 3.3 5420 " B " " 1 - 0.0902 - - 4990 " C " " 44 12.91 0.0917 0.2065 3.4 5510 Uncaptured A 1915 19.1 9 3.47 0.1041 0.3170 2.2 5420 " B " " 48 17.66 0.1023 0.2712 2.7 5250 " C " " 59 17.74 0.0992 0.2050 3.3 5590

Figures

FIGURE 1. Photos in life of (A) holotype of Cophixalus cupricarenus (BPBM 20223), (B) paratype of Cophixalus cupricarenus (BPBM 20208), (C) paratype of Cophixalus kethuk (BPBM 20202), (D) paratype of Cophixalus iovaorum (BPBM 19280), (E) paratype of Cophixalus desticans (BPBM 15703), and (F) paratype of Cophixalus desticans (BPBM 16434).

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 8. Complete call sequence of Call “ B ” (see Table 5) from holotype of Cophixalus iovaorum (BPBM 19287) recorded at Siruohu, W slope Mt. Obree, 1560 m elevation, Central Province, Papua New Guinea, at 1910 h on 29 January 2004. Air temperature 18.3 ° C.

FIGURE 9. (A) Waveform, (B) power spectrum, and (C) spectrogram of call “ A ” (see Table 5) of holotype of Cophixalus iovaorum (BPBM 19287) recorded by F. Kraus at Siruohu, W slope Mt. Obree, 1560 m elevation, Central Province, Papua New Guinea, at 1910 h, 29 January 2004. Air temperature 18.3 ° C.

Tables

TABLE 4. Mensural data for type series of Cophixalus iovaorum sp. nov. Data include only adult animals. * n = 1. Character Males (n = 29) Females (n = 2)

	mean	range	mean	range
SV (mm)	14.5	13.2–16.0	16.9	16.6–17.2
TL/SV	0.45	0.42–0.49	0.42	0.41–0.42
EN/SV	0.070	0.062–0.077	0.065	0.064–0.066
IN/SV	0.12	0.11–0.13	0.11	0.11–0.11
SN/SV	0.13	0.12–0.14	0.13	0.13–0.13
TY/SV	0.062	0.048–0.074	0.065	0.064–0.066
EY/SV	0.14	0.13–0.15	0.12	0.12–0.12
HW/SV	0.37	0.34–0.41	0.34	0.32–0.36
HL/SV	0.33	0.30–0.35	0.31	0.31–0.31
3rdF/SV	0.026	0.022–0.031	0.026	0.026*
4thT/SV	0.045	0.039–0.049	0.042	0.042*
EN/IN	0.59	0.53–0.65	0.58	0.58–0.58
3rd F/4th T	0.57	0.52–0.65	0.60	0.60*
HL/HW	0.90	0.80–0.98	0.91	0.85–0.96