Kurixalus wangi, Wu, Shu-Ping, Huang, Chuan-Chin, Tsai, Chi-Li, Lin, Te-En, Jhang, Jhih-Jia & Wu, Sheng-Hai, 2016

Wu, Shu-Ping, Huang, Chuan-Chin, Tsai, Chi-Li, Lin, Te-En, Jhang, Jhih-Jia & Wu, Sheng-Hai, 2016, Systematic revision of the Taiwanese genus Kurixalus members with a description of two new endemic species (Anura, Rhacophoridae), ZooKeys 557, pp. 121-153 : 131-137

Taxon classification Animalia Anura Rhacophoridae

Kurixalus wangi sp. n. Figs 3B, 4B, 5B, 6B, 7C, D, 8; Table 1, Table S5, Table S6, Table S7

Material examined.

Holotype. ASIZAM 0055 (Figs 3B, 9, Table 1), adult male collected on Shouka timber trail , 400 meters above sea level, Pingtong County, Taiwan (Fig. 1, Blue dots, 22°14'41.12"N, 120°49'50.14"E), 9 February 2005 by Shu-Ping Wu .

Paratypes. NCHUZOOL 11161-62 , collected on 13 September 2005 by Sheng-Hai Wu at Shuan-Liu , Pingtung County (22°13'15.58"N, 120°49'21.92"E) ; NCHUZOOL 11314 , 11318 , 11321-32 , collected on 20 October 2005 by Shu-Ping Wu, on Shouka timber trail , Pingtung County , NCHUZOOL 11315 , collected on 8 December 2005 by Shu-Ping Wu at Nanjenshan , Pingtung County (22°05'08.32"N, 120°51'24.04"E) ; NCHUZOOL 11316-17 , 11319 , collected on 20 December 2005 on Shouka timber trail , Pingtung County ; NCHUZOOL 11334-35 , collected on 7 December 2005 by Shu-Ping Wu, on Shouka timber trail , Pingtung County ; NCHUZOOL 11441 (tadpoles and eggs), ASIZAM 0056 and NCHUZOOL 11445-47 , collected on 9-12 February 2006 by Shu-Ping Wu, on Shouka timber trail , Pingtung County .

Type locality.

Shouka timber trail, 400 meters above sea level, Pingtung County, Taiwan, Republic of China (Fig. 1, Loc. 21, 22°13'15.58"N, 120°49'21.92"E).

Diagnosis.

A small to moderate-sized Kurixalus . Females snout-vent length averaging about 34 mm (range: 30.8-37.1 mm); males averaging 30 mm (range: 28.6-31.6 mm). Iris golden-yellow. Two anterior horns of the X-shaped marking on back extending to eyelid. Webbing extensive on toes, extending to the toe disc on the inner margin of toe V. Belly and throat whitish. Anterior margin of tadpole dorsal fin extending to posterior body. Tadpole with almost no pigment on region of tail muscle. Upper lip of tadpole with shallow transverse furrow.

Etymology.

The epithet is named and dedicated to Mr. Ching-Shong Wang for his pioneering work and contributions to the herpetology of Taiwan ( Wang 1962). Mr. Wang discovered two rhacophorid frogs ( Rhacophorus taipeianus and Kurixalus idiootocus ) ( Liang and Wang 1963, Kuramoto and Wang 1987) in Taiwan and suggested, in the early 1980s, that some Kurixalus specimens collected near the type locality of this new species might be different from Kurixalus eiffingeri (personal communication). The name is used in the genitive case.

Description of holotype.

Habitus slender, body flat, small (SVL 29.3 mm), head wider than long, snout shape in dorsal view subovoid with pointed tip; profile acuminate, slightly protruding; canthus rostralis distinct, rounded; loreal region oblique, slightly concave; nostril oval and oblique; nostril closer to tip of snout than to eye; internarial distance equals nostril to eye distance; nostril to eye distance smaller than eye diameter; interorbital distance subequal to internarial distance and eyelid width; pupil horizontally oval; tympanum distinct, round, upper margin covered by curved supratympanic fold, which runs from posterior angle of eye to arm; angle of jaw at level of middle of tympanic ring; tympanum less than half of eye diameter; tympanum to eye distance greater than half tympanum diameter; premaxillary and maxillary teeth present; choana exposed; vomerine odontoid in oval patch, equal in diameter to choana; vomerine teeth present; tongue large, forked and shallowly emarginate; no lingual papilla; vocal slits long, near commissure of jaw on floor of mouth.

Limbs moderately robust; forearm shorter than hand; tips of fingers expanded into discs with ventro-marginal and transverse grooves; disc of finger III about 2/3 of tympanum diameter; finger length I<II<IV<III; disc even, truncate, with indistinct transverse groove; size of disc I<II<III<IV; disc of finger I small, same width as phalanx width; phalanges emarginate with trace of webbing; subarticular tubercles prominent, rounded, globular; prepollex expanded, rounded; glandular skin associated with nuptial pad from base of disc I on medial and dorsal side of pollex; palmar tubercle double, oval, subequal in size; supernumerary tubercles small; outer margin of fourth finger with longitudinal flat tubercles connected into a weak flap.

Heels overlapping when adpressed; hind limb moderate in length; shank shorter than thigh and longer than foot; tips of toes expanded into discs with ventro-marginal and transverse grooves; relative length of toes I<II<III<V<IV; relative size of discs I<II<III<IV<V; disc on toe I same width as phalanx width; discs truncate and with indistinct transverse grooves. Webbing moderate on all toes; webbing formula I(1) –(trace)II(0.5)–(1.5)III(1)–(2)IV(1)– (0.2)V; weak dermal fringe on outer side of toe V, from posterior tarsus to base of disc V, formed by continuous elongated papilla; subarticular tubercles rounded, slightly conical; subarticular tubercle on proximal joint on toe IV smaller than the others; inner metatarsal tubercle oval, small; outer metatarsal tubercle absent; supernumerary tubercle absent; small white-tipped tubercle on heel.

Skin shagreen, tubercles not present on back; ventral surface slightly granular, white tipped dermal tubercles on posterior thigh. Series of tubercles near lateral margin of upper eyelids; skin smooth on flank; white tipped tubercles on lateral lower arm in ventral view.

Color. In preservative, dorsum grayish with black irregular spots; patches of dark brown markings on median eyelid, forming triangular X-shaped blotch; two posterior branches of the X marking terminated at middle of dorsum; two dark blotches on posterior back; flank with dark oblique irregular band demarcating grayish dorsum and whitish venter; dark irregular blotches on loreal region, antero-ventral corner of eye, and tympanum; black band from anterior eye angle, through nostril to tip of snout; gular region sprinkled with black spots; upper arm with three wide bands, thigh and shank with three bands; ventral surface orange, speckled with brown spots on gular region; vent with large dark brown blotch over cloacal opening, surrounded ventrally and dorsally by white tubercles (Figs 3B and 8).

Color in life, iris golden-yellow; dorsum dark brownish-green scattered with deep brown and black spots, with dark X marking on anterior half of dorsal surface; tympanic membrane light brown to milk-white; white and rounded tubercle located on outer fringe of heel (Fig. 3B).

Variation. Females were 14% larger than males (Table 1) (t-test, p <0.01). Males had longer hands than females. Sexual dimorphism is evident in the possession of nuptial pads and the hypertrophied upper and lower arms in males. Females possess supracloacal dermal flaps (absent in males). The dorsum color of both genders ranges from light brown with distinctly dark markings to almost uniformly light green. Webbing patterns between the two outer metatarsals vary. Among the 69 specimens examined, one was not webbed, and two were 2/3 webbed, and the rest of the specimens were half-webbed or less. Measurements of holotype and other type specimens are shown in Table 1.

Description of eggs and tadpoles.

Average diameter of eggs from 4 clutches was 3.37 ( ± 0.27) mm with capsule (n = 38) and 1.74 ( ± 0.09) mm without capsules; eggs were creamy yellow with developing embryos. The range of total length of ten tadpoles between stages 27-32 was 13.19-22.64 mm (Fig. 4B; Table S4).

Dorsal surface of tadpoles dark brown; ventral surface white; pigment on tail confined mostly to upper half of tail muscle; tail fins transparent; body ovoid in lateral view, flat and sloping above, rounded below; eye dorsal, not visible from below, located on anterior 1/3 of body; nostril lateral; distance from nostril to upper lip much shorter than to eye; internarial distance subequal to interorbital distance; eye-nostril distance less than internarial distance. Face with slightly elevated ridge, from rostrum to upper lip (Fig. 5B). Oral disc terminal, opening anteriorly; lower lip slightly protruding; lateral half of upper lip with a single row of papilla; a single row of short papil lae on lower lip without median interruption. Tooth row formula 3(3)/2(1); the first and second rows on upper lip long, traverse entire width of upper labium; the third upper tooth row only visible when the entire upper lip is upturned, very short, confined to the lateral-most edge of the upper labium. The first tooth row on lower labium interrupted medially by a gap half the width of the lower jaw, the second tooth row short, less than half of oral disc width. Lower beak visible only in youngest tadpoles, black in color, upper beak straight, with very short lateral processes, upper beak ridged in middle; lower beak serrated on inner surface; older tadpoles all have broken upper beaks, lower beak white; spiracle sinistral, not tubular; opens at center of body, visible in ventral aspect. Vent dextral, opening at lower edge of ventral fin; tail deeper than body at center; dorsal and ventral fin equal in depth, tail muscle moderately strong. Dorsal fin origin on posterior body (Figs 5B and 6B).

Distribution and ecological notes.

Kurixalus wangi sp. n. is distributed in the southern part of Pingtung County in southern Taiwan below 500 meters above sea level (Fig. 1, Blue dots). All specimens were collected in the shrubs of secondary forests or lowland broad-leaved forests at low altitudes.

Mating calls.

Mating calls were heard in bushes or on tree branches up to 3 m above the ground between September and March, peaking in December. A slow call and a rapid call were identified. Both types of call consisted of a single beeping sound. Slow calls recorded in the field had an average duration of 99 ( ± 19) ms (n = 30, equivalent hereafter) and rapid calls had an average duration of 57 ( ± 15) ms. Intervals between notes were 1122 ( ± 230) ms (slow calls) and 115 ( ± 22) ms (rapid calls). For the slow and rapid calls, the maximum frequencies of calls were 3185 ( ± 194) Hz (slow calls) and 3072 ( ± 47) Hz (rapid calls); the minimum frequencies of calls were 2399 ( ± 122) Hz (slow calls) and 2565 ( ± 62) Hz (rapid calls). (Fig. 7C, D; Table 2). The diagrams of all Kurixalus species’ calls from Taiwan are illustrated in Fig. 7 and detailed in Table 2.

Eggs were discovered in tree hollows, plastic pipes embedded in retaining walls on slopes (Fig. 4B), and discarded plastic cups on the forest floor. Eggs of some clutches adhered in a single layer to the walls above water; others were submerged in water. The average clutch size was 70 (n = 7, range: 56-104). Tadpole stomachs contained yellow yolky substances, suggesting that the tadpoles might have ingested eggs recently.

Morphological comparisons.

Within-species comparisons showed that the body size was differentiated by sex in Kurixalus eiffingeri and Kurixalus wangi sp. n., but not in Kurixalus berylliniris sp. n. (Table 1, Table S5). Among-species comparisons indicated that males were significantly different in body size (p <0.001, Table S5). ANCOVA tests showed that the three species were significantly different in all morphometric characteristics. For the ANCOVA of male morphometric data, all characters differed significantly, and 17 characteristics exhibited significant variation in size-adjusted means (Table S6). In females, all characteristics also differed in slopes, and eight characteristics exhibited significant variation in size-adjusted means. A repeated ANOVA comparing the two new species and Kurixalus eiffingeri showed that all morphometric characteristics differed significantly among species between males and females (Table S6).

In the PCA, after eliminating the effect of size by using a normalizing ratio (measurements divided by SVL) and omitting the five non-normal morphometric characteristics (HL, EN, TAD, D3L, TL), 23.98% of the variation was associated with body size (Table S7). The large-sized Kurixalus berylliniris sp. n. was separated from the other three species, while Kurixalus idiootocus and Kurixalus wangi sp. n. overlapped considerably (Fig. 9A). In the plot of two shape components (Fig. 9B, Table S7), Kurixalus berylliniris sp. n. and Kurixalus eiffingeri are clearly differentiated from the other two species Kurixalus idiootocus and Kurixalus wangi sp. n.

Mating call comparisons.

The calls of the two new species and of Kurixalus eiffingeri were found to be different in maximum frequency, single note duration, and time interval between notes of mating calls. The minimum frequency among the three species was not different (Table 3).