Callulops taxispilotus, Kraus, 2019

Kraus, Fred, 2019, A revision of Callulops doriae (Anura: Microhylidae), with descriptions of four new species, Zootaxa 4612 (1), pp. 1-28 : 19-22

publication ID	https://doi.org/ 10.11646/zootaxa.4612.1.1
publication LSID	lsid:zoobank.org:pub:33E82826-EF18-47F0-B804-CC877BD2AFFE
persistent identifier	https://treatment.plazi.org/id/ED72CB05-FF86-FFF1-82FA-FF5F7F79FE22
treatment provided by	Plazi
scientific name	Callulops taxispilotus
status	sp. nov.

Treatment

Callulops taxispilotus View in CoL , sp. nov.

Figs. 1G, H View FIGURE 1 urn:lsid:zoobank.org:act:0B199019-F168-486D-A35A-0B8C0C4F0D1F

Xenorhina doriae View in CoL (part) Zweifel, 1972: 53. Phrynomantis doriae View in CoL (part) Burton, 1986: 415 [by implication]. Callulops doriae View in CoL (part) Dubois, 1988: 3 [by implication].

Holotype. ―USNM 581333 (field tag BSFS 11810), adult female collected by D. Bickford 11 August 1998 at Pio River site, 10 km SSE Haia, 6.7892° S, 144.9920° E, 490 m a.s.l., Gulf Province, Papua New Guinea. GoogleMaps

Paratypes (n = 16). Astrolabe Range, Central Province, Papua New Guinea ( BMNH 1932.10.2.96); Moroka , Central Province, Papua New Guinea, L. Loria, August–November 1893 ( MSNG 29435 ) ; Bomai , Tive Plateau, Chimbu Province, Papua New Guinea, F. Parker, 28 May 1965 ( AMNH 76462 ) , 22–28 May 1965 ( CAS 107484– 85 , MCZ 59898–901, 60802–04); Nimi River View Materials , Chimbu Province, Papua New Guinea, F. Parker, 29 September 1967 ( MCZ 64404) ; Pio River , Chimbu Province, Papua New Guinea, F. Parker, 27 September 1967 ( MCZ 64406) ; Wara O’Oh , Chimbu Province, Papua New Guinea, D. Bickford, June 1996 ( USNM 581332 ) ; Kokoro , Gulf Province, Papua New Guinea, B. Beehler, 7 September 1979 ( BPBM 16931 ) .

Diagnosis. Callulops taxispilotus sp. nov. is distinguished from all other members of the genus by its unique combination of large size (adult SV = 71.0– 93.8 mm); circum-marginal grooves usually absent on fingers and toes but present in some populations; short leg (TL/SV = 0.38–0.43); highly pustulose dorsum; loreal region with a moderately swollen protuberance; large tympanum (TY/SV = 0.053 –0.068); large eye (EY/SV = 0.064 –0.098); wide head (HW/SV = 0.35–0.41, HL/HW = 0.69–0.85); basal subarticular tubercle of 4th toe absent; dorsum brown with large black warts largely arrayed in a few rows, some of the lateral and posterior warts with small white tips; groin, and hidden surfaces of legs blotched with white or orange; limbs same color as dorsum; venter gray or gray brown.

Comparisons with other species. Callulops taxispilotus sp. nov. differs from all other species of the genus except C. doriae , C. neuhaussi , C. argus sp. nov., C. bicolor sp. nov., and C. stellatus sp. nov. in its dark-spotted dorsum and large orange or white blotches in the groin and on the hidden surfaces of the thighs. The mid-dorsal pattern of large, solid, black warts is unique within this complex, although C. argus sp. nov. and paler C. stellatus sp. nov. could be viewed as somewhat similar (cf. Figs. 1C, F View FIGURE 1 vs. 1G). However, C. argus sp. nov. differs from C. taxispilotus sp. nov. in having distinct ocelli with large white centers across its entire dorsum whereas C. taxispilotus sp. nov. has at best only a few black warts with small white tips, and these are almost always present only laterally and/or posteriorly. Further, C. taxispilotus sp. nov. differs from C. argus sp. nov. in having a larger tympanum (TY/SV = 0.053 –0.068 vs. 0.049 in C. argus sp. nov.), larger eye (EY/SV = 0.064 –0.098 vs. 0.057 in C. argus sp. nov., EY/SN = 0.62–0.96 vs. 0.60 in C. argus sp. nov.), and wider head (HW/SV = 0.35–0.41 vs. 0.30 in C. argus sp. nov., HL/HW = 0.69–0.85 vs. 0.88 in C. argus sp. nov.). Callulops taxispilotus sp. nov. further differs from paler specimens of C. stellatus sp. nov. ( Fig. 1F View FIGURE 1 ) in its much larger size (adult SV = 71.0– 93.8 mm vs. 59.3–71.3 mm in C. stellatus sp. nov., mass of one 85 mm male = 65.0 g vs. 20.7–43.3 g in the series of adult C. stellatus sp. nov.), larger eye (EY/SN = 0.064 –0.098 vs. 0.058 –0.067 in C. stellatus sp. nov.), longer head (HL/SV = 0.27–0.32 vs. 0.23–0.28 in C. stellatus sp. nov.), lacking a metacarpal tubercle at the base of T4 (present in C. stellatus sp. nov.), and having a sparser density of dark dorsal warts than C. stellatus sp. nov. (cf. Fig. 1G View FIGURE 1 vs. 1F). Callulops taxispilotus sp. nov. is easily distinguished from C. doriae in its pattern of relatively few large black warts dorsally (vs. dense pattern of irregular brown flecks and spots in C. doriae ) and its much wartier juveniles (juveniles smoother in C. doriae , cf. Fig. 1B View FIGURE 1 vs. 1H); it is even more easily distinguished from C. bicolor sp. nov. by the pale yellowish dorsum with ocelli and black limbs and venter of that species (see Fig. 1D View FIGURE 1 vs. 1G). Callulops taxispilotus sp. nov. further differs from C. neuhaussi in its much larger size (adult SV = 71.0– 93.8 mm vs. 59.4 mm in a maturing female C. neuhaussi ), shorter leg (TL/SV = 0.38–0.43 vs. 0.46 in C. neuhaussi ), and in having the limbs the same color as the dorsum (vs. darker than dorsum in C. neuhaussi ).

Description of holotype. An adult female with left-lateral and ventral L-shaped incision. Head wide (HW/SV = 0.40), wider than long (HL/HW = 0.74), with swollen loreal region, moderately inflated immediately anterior to eye, concave posterior to naris; upper lip inflated; canthus absent; nostrils approximately circular, directed laterally but slightly dorsally too, closer to tip of snout than to eyes; internarial distance equal to distance from naris to eye (EN/IN = 1.0; IN/SV = 0.73; EN/SV = 0.73); snout slightly rounded, almost truncate when viewed from side, truncate when viewed from above; eyes large for the genus (EY/SV = 0.091); eyelid less than interorbital distance; tympanum clearly demarcated, smaller than eye (TY/EY = 0.58; TY/SV = 0.053), annulus bordered posteriorly and dorsally by heavy supratympanic fold that extends from behind eye to posterior of tympanum, where it bends sharply to end in front of forearm insertion below level of jaw; supratympanic fold a clearly demarcated ridge ventrally but evenly continuous with dorsal skin. Dorsum, sides, and tops of limbs heavily pustulose and glandular; ventral surfaces smooth anteriorly, weakly granular on abdomen, more strongly granular under thighs. Fingers unwebbed, thick, all bearing discs without terminal grooves; relative lengths 3>4≈2>1. Finger discs one-third again as wide as penultimate phalanges (3rdF/SV = 0.033). Subarticular tubercles large, well developed, covering much of phalangeal surfaces; inner and outer metacarpal tubercles low, large, and oval; medial metacarpal skin thickening large. Toes unwebbed, all bearing discs without terminal grooves, except that T4 and T5 on right foot cannot be assessed because they are missing; relative lengths 4>3>5>2>1. Toe discs barely wider than penultimate phalanges (4thT/SV = 0.039), wider than those of fingers (3rdF/4thT = 0.83). Subarticular tubercles well developed, rounded, only two on fourth toe, none present at junction of metatarsal and proximate phalanx on fourth toe; inner metatarsal tubercle a large, prominent oval; outer a poorly defined skin thickening. Legs short (TL/SV = 0.40).

In preservative, dorsal ground color dark brown, changing to yellow brown laterally; tops of limbs same. Dorsum with many large black warts more-or-less arranged in rows, between which are many smaller black warts; dorsal warts lack white centers except for two in the sacral region; lateral and dorsolateral warts have tiny white centers as far forward as forearm insertion. Venter yellow brown, darker on chin and throat and under legs, lighter on abdomen. Anterior and posterior surfaces of thighs dark brown with many large yellow blotches; under shanks and ankles same; under thighs and forearms brown with few small yellow spots. Palmar and plantar surfaces gray brown. Iris very dark brown.

Measurements of holotype (in mm). —SV = 84.5, TL = 34.2, HW = 33.7, HL = 24.8, IN = 6.2, EN = 6.2, SN = 9.0, EY = 7.7, TY = 4.5; 3rdF = 2.75, 4thT = 3.30.

Variation. I cannot reliably assess sexual differences in mensural features because I lack sexual identity for most specimens. However, in the sample of adults available, a few features have moderately broad ranges of variation (e.g., EY/SN, TY/EY, 3rdF/4thT, Table 5 View TABLE 5 , Appendix II). Most likely, the variable quality of preservation of a few specimens contributes to most of that variation, especially inasmuch as disc widths are prone to distortion due to desiccation, and eye diameter is often unreliably measured if the eyes are largely closed. Despite this, most specimens are well preserved, and standard deviations are small for most characters ( Table 5 View TABLE 5 ), suggesting that the available sample presents a reliable picture of morphometric variation in this species.

One important feature varies geographically: The digits lack circum-marginal grooves in almost all specimens from the area of the Tive Plateau. However, USNM 581332 from Wara O’Oh Camp, 10 km SSE Haia, 6.7886° S, 145.0367° E, 550 m a.s.l., Chimbu Province, is an exception to this, as are the three specimens from the Papuan Peninsula (BPBM 16931, MSNG 29435, BMNH 1932.10.2.96), for which grooves are present on all digits. This raises the possibility that this feature varies geographically, although sample sizes are not large enough to evaluate this possibility in detail. The four specimens involved do not differ importantly in morphometric averages or ranges for any other features or in color pattern, so there is no reason to presume that two different species are involved.

The sole juvenile in the type series has a relatively larger snout, larger eye, and smaller tympanum than do the adults ( Table 5 View TABLE 5 ). This specimen is also much wartier than the adults ( Fig. 1H View FIGURE 1 ).

Color pattern of all specimens is similar to that seen in the holotype, though with some variation. The dorsal ground color varies from medium brown to yellowish brown, and small dark-brown flecks between the rows of large black dorsal warts vary from obscure to well defined. The dorsal warts typically lack small white centers except laterally and posteriorly, but MCZ 59899―the smallest adult at 71 mm―also has a few white-tipped black warts on the shoulders, as apparently did MCZ 59898 in life ( Fig. 1G View FIGURE 1 ). The venter is typically yellow brown and darker brown along the chin, but MCZ 64406 is also darker brown under the throat and chest; CAS 107485 is flecked with straw yellow from the chin to chest. Undersides of the thighs are typically uniformly yellow brown, but there may be faint indications of yellow flecks in some specimens. Front and rear of thighs typically have a few large yellowish or orange blotches, but MCZ 60802 has fewer on the anterior of the thigh than do other specimens. The sole juvenile (MCZ 60804, SV = 37 mm) is much darker than the adults, with small bluish-white spots scattered across all dorsal surfaces ( Fig. 1H View FIGURE 1 ), and its venter is dark brown flecked with yellow.

Color in life. The color pattern of the holotype (USNM 581333) in life was recorded as “Brown with numerous darker warts turning pale ventrally. Orange/pink spots on inguinae and hidden aspects of legs. Ventrally pale greybrown.” Paratype USNM 581332 had a dark-brown ground color dorsally that was lighter distally and laterally but solid black mid-dorsally; many large black warts with white tips on the lateral and posterior warts; ventral surfaces dull gray, darker anteriorly; and hidden surfaces of the thighs and inguinae black with bright-orange blotches (D. Bickford, field notes for both).

From the field notes of Fred Parker: MCZ 59899 and 59901 were dull red brown dorsally with the heads blackish brown; face dark brown with some white specks between eye and corner of mouth; dorsal warts black brown, with the lateral and posterior few having white tips; hands and arms dark brown with fine white specks; groin and hidden surfaces of thighs dark brown with white blotches; venter purplish brown, chin to chest darker with white specks, abdomen paler with white specks ventrolaterally; palmar and plantar surfaces gray. MCZ 59898 had a paler red-brown dorsum ( Fig. 1G View FIGURE 1 ) and paler ground color laterally and ventrally; mid-belly almost gray, blotched with brown. MCZ 59899 was much darker than the other specimens. The hidden surfaces of all the AMNH, CAS, and MCZ specimens collected by F. Parker were dark brown with white blotches (changing to pink upon euthanasia); irises of all were dull silvery gray with horizontal pupils. The sole juvenile (MCZ 60804) was very dark black brown with black, white-tipped tubercles ( Fig. 1H View FIGURE 1 ); face, flanks, and limbs black speckled with white; under chin, throat, chest, and limbs dull brown speckled with black, abdomen more translucent.

Call. The call is unrecorded; and none of the animals collected by Fred Parker or David Bickford―which com- prise the large majority of specimens―was heard to call (F. Parker, pers. comm.; D. Bickford, field notes). BPBM 16931 was heard to call but was not recorded, having been captured by an ornithologist.

Etymology. The name is a masculine compound adjective from the Greek taxis, meaning line or row, and the Greek spilos, meaning spot. It refers to the tendency of the large, black dorsal warts to be arrayed in a few rows.

Range. Known from several localities along the southern versant of the Central Highlands and Owen Stanley Mts. from Central, Chimbu, and Gulf provinces ( Fig. 4 View FIGURE 4 ). Localities for the specimens from Chimbu Province are sufficiently precise that the elevational range of this species in that region can be calculated as 400–1020 m a.s.l. BPBM 16931 was reportedly collected at Kokoro ± 70 m a.s.l. Inasmuch as Kokoro stands at 50 m a.s.l. and it is many kilometers to get to a lower elevation but hills rise behind the village, this suggests that the specimen came from 50–120 m a.s.l. These data suggest that this species is likely to range from near sea level to a little more than 1000 m a.s.l. The less precise collecting localities of Moroka and the Astrolabe Range are both within this elevational range.

Ecological notes. The majority of specimens collected by Fred Parker (AMNH, CAS, and MCZ specimens) was taken in and under decaying debris and tree trunks, but the juvenile was found on a forest track at night (F. Parker, pers. comm.). USNM 581332–33 were taken on the forest floor (D. Bickford, field notes); BPBM 16931 was taken while calling from between the flanks of a tree buttress.

USNM 581332–33 secreted copious quantities of a sticky white exudate from the dorsal warts (D. Bickford, field notes), and BPBM 16931 probably did as well inasmuch as notes for the specimen stated that it was covered by “slime”.

One female (BPBM 16931) is immature at 82.2 mm, but other females are mature at 79.1, 84.5, and 86.6 mm, suggesting that females mature at approximately the size of 79–83 mm SV. Two males of 79.5 and 85.4 mm SV are both mature.

Remarks. A drawing of a specimen (AMNH 76462) of this species that well illustrates the linear array of sparse dorsal black warts was illustrated by Zweifel (1972, fig. 73).