Kurixalus berylliniris, 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 : 125-129

Taxon classification Animalia Anura Rhacophoridae

Kurixalus berylliniris sp. n. Figs 2, 3A, C, D, 4A, 5A, 6A, 7A, 7B, 8B; Table 1, Table S5, Table S6, Table S7

Material examined.

Holotype. ASIZAM 0053 , an adult male (Figs 2 and 3A, Table 1), collected on Ligia timber trail, 1250 m elevation, Taitung County, Taiwan (Fig. 1, Loc. 20, 22°49'26.79"N, 121°00'35.45"E), 15 September 2005 by Shu-Ping Wu .

Paratypes. NCHUZOOL 11311-13 collected on 2 August 2005 by Hui-Ming Huang at the type locality ; NCHUZOOL 11431 , ASIZAM 0054 collected on 15 September 2005 by Shu-Ping Wu at the type locality ; NCHUZOOL 11442 (eggs and tadpoles), collected on 7 February 2006 by Shu-Ping Wu at the type locality ; NCHUZOOL 11448 , collected on 16 February 2006 by Shu-Ping Wu at 425 meters above sea level, at Antong , Hualien County (Fig. 1, Loc. 19, 23°17'06.62"N, 121°21'44.82"E) .

Type locality.

Ligia timber trail, 1250 meters above sea level, Taitung County, Taiwan, Republic of China (Fig. 1, Loc. 20, 22°49'26.79"N, 121°00'35.45"E).

Diagnosis.

A moderate-sized Kurixalus . Females average about 41 mm snout-vent length (range: 27.6-46.3 mm); males average about 35 mm (range: 29.0-42.3 mm). Iris emerald to light green. Two dark brown spots on eyelids, separated from each other and from X-shaped blotch on dorsum. Subarticular tubercles on foot rounded and flat. Belly and throat white or faintly-speckled. Prepollex in males squarish, compressed and expanded. About half-webbed between two outer toes. Anterior margin of tadpole dorsal fin extending to body. Tadpole heavily dark brown to black pigmented in gular region and on tail muscle. Upper lip of tadpole with deep transverse furrow, and prominent ridge extending from upper lip to anterior margin of nostril (key of tadpole, 3).

Etymology.

The epithet berylliniris is a compound word formed from beryllin (L.), green-colored, and from iris (L.), iris of the eye, and is treated as a noun in nominative singular in opposition to the generic name.

Description of holotype.

Habitus moderately slender and somewhat flattened, size moderate (SVL 40.1 mm); head wider than long; tip of snout pointed; snout obtuse in lateral view; nostril barely visible from above; canthus rostralis curved, prominent; loreal region concave, oblique; interorbital distance 1.5 times wider than upper eyelid width; nostril oval, oblique, closer to tip of snout than to eye; internarial distance slightly longer than nostril-eye distance; eye diameter larger than nostril-eye distance; pupil horizontal; tympanic region oblique; diameter of tympanum approximately half of eye diameter; tympanum distinct, round; tympanum to eye distance smaller than half tympanum diameter; supratympanic fold from posterior tip of eye to base of arm; jaw angle almost to posterior rim of tympanum; premaxillary and maxillary teeth present; choana exposed; vomerine teeth present only on left side; tooth patch oval, about half of choana diameter. Vocal slits near commissure of jaw, slit-like.

Limbs slender; tips of all four fingers expanded into discs with ventro-marginal and transverse grooves; disc of finger III about 67% of tympanum diameter; relative finger lengths: I<II<IV<III; relative disc widths I<II<III<IV; disc on finger I small, slightly wider than phalanx width. Webbing more extensive on right hand; only trace of webbing on left hand between fingers III and IV; webbing formula on right hand: I(1.5) –(1.5)II(2)–(2)III(1)– (1.5)IV; subarticular tubercles rounded, elevated, larger under phalanges than at base of fingers; supranumerary tubercles present, smaller than subarticular tubercles; two palmar tubercles, outer longer but narrower than inner. Nuptial pad greatly expanded, proximal edge more flattened than at base; epidermal glands discontinuous, on lateral margin of nuptial pad, and on internal margin of finger I; outer margin of hand with series of longitudinal tubercles somewhat connected to weak skin folds.

Heels overlapping when adpressed; tips of toes expanded into discs with ventro-marginal and transverse grooves; relative length of toes: I<II<V<III<IV; relative width of toe discs: I<II<III<IV<V; disc on toe I small, truncated; disc widest on toe V, less than twice of width of phalanx; webbing formula: I(0.5) –(1)II(0.5)–(1.5)III(1)–(2)IV(1)– (0.5)V; subarticular tubercles rounded, elevated, those at base of toes III, IV, and V smaller than supernumerary tubercles; inner metatarsal tubercle flat, oval, median margin free; outer metatarsal tubercle absent; a series of tubercles on outer surface of tarsus to outer margin of toe V.

Dorsum granular with small tubercles; palpebral tubercles absent; flank and venter smooth or slightly shagreened.

Color. In preservative, two dark brown spots on eyelids; dorsum at shoulder region with a large irregular X-shaped blotch; anterior horn of blotch not continuous with spots on eyelids; two brown blotches on lower back in groin region; flank white with large irregular blotches; dark blotches at cloacal opening, surrounded ventrally by white tubercles; loreal region with dark brown irregular spot; dark spots also present under eye, on posterior part of upper lip near jaw joint, and on supratympanic fold; arm with one thick cross bar on upper arm, two on forearm, one on outer palm; three transverse bars on thigh and on tibia; medial palm and foot white on dorsal surface; venter white; few irregular brown spots on chest, faintly maculated on gular region (Figs 2 and 3A).

Color in life. iris emerald to light green; dorsum dark green to deep tan with a black X-shaped and irregular blotches; tympanum light yellowish-brown with small dark spots; medial surface of hand and foot creamy white; venter cream sprinkled with minute black spots in gular region (Fig. 3A, C, D).

Variation. Sexual dimorphism was evident in the possession of nuptial pads and the hypertrophied upper and lower arms in males. Females were 10% larger than males (t-test, p> 0.05). Females possess a supra-cloacal flap (absent in males). The species has dark and white morphs. The dark morph is similar to the holotype (Fig. 3A). In the white morph, the dorsum is light emerald green, and the dorsal X pattern is obscured (Fig. 3C, D). Measurements of the holotype and paratypes are shown in Table 1.

Description of eggs and tadpoles.

Average diameter of the eggs was 4.55 ( ± 0.25) mm (n = 5) with capsule and 1.79 ( ± 0.09) mm (n = 8) without capsule. The eggs were creamy yellow with developing embryos. The range of total length of five preserved tadpoles between stages 26-33 was 17.64-30.00 mm (Fig. 5A; Table S4).

Dorsal surface of tadpoles dark brown; ventral surface white; tail fins almost transparent with many faint black flecks; region of tail muscle heavily pigmented, especially anteriorly; body ovoid in lateral view, compressed above, more rounded below; eyes dorsal, not visible from below; eyes on anterior 1/3 of body; nostril lateral, about half way between upper lip and eye; internarial distance 105% of interorbital distance; eye-nostril distance smaller than interorbital distance; a very prominent and elevated ridge extending from nostril to upper lip; a deep transverse groove present in posterior to upper lip; a longitudinal groove on either side of head from lateral rim of upper lip to level between nostril and eye (Fig. 5A). Oral disc terminal, opening anterodorsally; lateral half of upper lip with a single row of papillae; lower lip slightly protruding; a single row of short papillae on lower lip without median interruption. Tooth row formula 3(3)/1(1) or 3(3)/0 or 3(3)/1; the first and second tooth rows on upper lip long, traverse entire width of upper labium; the third upper tooth row only visible when entire upper lip is upturned, very short, abutting lateral-most edge of second row; lower labium teeth lost in most specimens. Upper and lower beak black; upper beak straight, with median notch and moderately long lateral process, upper beak with medial transverse ridge; lower beak serrated on inner surface. Spiracle sinistral, not tubular; opening at center of body, visible in ventral aspect.

Vent dextral, opening at proximal edge of ventral fin; tail moderately strong, deeper than body; dorsal and ventral fin depth equal, almost symmetrical (or slightly deeper on dorsal fin); origin of dorsal fin anterior to that of ventral fin, on posterior 1/5 of body (Figs 5A and 6A; Table S4).

Distribution and ecological notes.

Kurixalus berylliniris sp. n. occurs in eastern Taiwan (at 225 to 1250 meters above sea level). The highest recorded elevation was on the eastern slope of the Central Mountain Range (Taitung County, 1250 meters above sea level), and the lowest recorded elevation was on the western slope of the Coastal Range (Hwalien County, 225 meters above sea level). Specimens were collected near the canopy level in moist broad-leaf forests in Taitung and on forest edges in Hwalien. The northern border of the specimen’s distribution was near the Guangfu township of the central Hualien County (Fig. 1, Green stain).

Mating calls.

Mating calls were heard during the winter months from November through February. Both a slow call and a rapid call consisted of a single beeping sound. Slow calls recorded in the field had an average duration of 158 ( ± 56) ms (n = 30, equivalent thereinafter); rapid calls had an average duration of 103 ( ± 42) ms. Intervals between notes were 3195 ( ± 1060) ms (slow calls) and 1562 ( ± 1442) ms (rapid calls). For the slow and rapid calls, the maximum frequencies of calls were 2901 ( ± 89) Hz (slow calls) and 2961 ( ± 71) Hz (rapid calls); the minimum frequencies of calls were 2517 ( ± 106) Hz (slow calls) and 2518 ( ± 124) Hz (rapid calls). (Fig. 7A B; Table 2).

Eggs and tadpoles were found in the pooled water in decaying trunks of tree ferns, Cyathea spinulosa . The eggs were adhered together in a single layer by colloidal gel and attached to the inner roof and wall above the water. A total of 62 eggs were counted in one tree hole (Fig. 4A). Tadpoles collected at stages 31 and 33 had a creamy yellow stomach, suggesting the tadpoles might have ingested eggs recently.