Kurixalus lenquanensis, Yu, Guohua, Wang, Jishan, Hou, Mian, Rao, Dingqi & Yang, Junxing, 2017

Yu, Guohua, Wang, Jishan, Hou, Mian, Rao, Dingqi & Yang, Junxing, 2017, A new species of the genus Kurixalus from Yunnan, China (Anura, Rhacophoridae), ZooKeys 694, pp. 71-93 : 74-77

Kurixalus lenquanensis sp. n. Figs 4, 5, 6, 7

Holotype.

KIZ 170180Y (Figs 4-6), an adult male, collected at 20:35 on 5 May 2016 by Guohua Yu from Lenquan Village (23°12'52"N, 103°22'34"E, 1622 m elevation; Fig. 1), Mengzi City, Yunnan Province, China.

Paratype.

Thirteen adult males: KIZ 170175 Y– 170179Y and KIZ 170181 Y– 170182Y collected at 20:00-22:45 on 5 May 2016 by Guohua Yu from type locality, KISD 1506203-1506204 collected at 21:00-21:30 on 20 June 2015 by Jishan Wang from the same locality as the holotype, and KIZ 170183 Y– 170186Y collected at 20:00-22:30 on 6 May 2016 by Guohua Yu from Yangjiatian Village (23°20'5.35"N, 103°9'30.33"E; Fig. 1), Gejiu City, Yunnan Province, China.

Type locality.

Lenquan Village, Mengzi City, Yunnan Province, China.

Etymology.

The name lenquanensis refers to Lenquan Village, the locality where the new species was found.

Diagnosis.

The new tree frog species is assigned to the genus Kurixalus based on a combination of the following characters: tips of digits enlarged to discs, bearing circum-marginal grooves; small body size (adult males SVL range of 25.0-28.9 mm; Table 4); finger webbing poorly developed and toe webbing moderately developed; serrated dermal fringes along outer edge of forearm and tarsus; an inverted triangle-shaped dark brown mark between eyes; dorsal brown ") (" saddle-shaped or X-shaped marking maybe present; and coarse dorsal and lateral surfaces with small, and irregular tubercles.

Kurixalus lenquanensis sp. n. can be distinguished from its congeners by a combination of the following characters: smaller body size (mean SVL 27 mm in males); obtusely pointed snout with no prominence on tip; curved canthus rostralis; slight nuptial pad; brown dorsal color; rough dorsum; chin clouded with brown; absence of large dark spots on ventral surface; presence of vomerine teeth; gold brown iris; single internal vocal sac; dermal fringes along outer edge of limbs; rough flanks; and granular throat and chest.

Description of holotype.

A small rhacophorid (SVL 27.2 mm); HL 89.4% of HW; snout obtusely pointed, no dermal prominence on tip, projecting slightly beyond margin of lower jaw in ventral view; SL (3.7 mm) shorter than ED (4.1 mm); canthus rostralis blunt and curved; lore region oblique, slightly concave; nostril oval, slightly protuberant, closer to tip of snout than eye; IND (2.5 mm) narrower than IOD (2.8 mm) and slightly wider than UEW (2.3 mm); pineal spot absent; pupil oval, horizontal; tympanum distinct (TD 1.6 mm), rounded, less than half ED; supratympanic fold distinct, curves from posterior edge of eye to insertion of arm; vomerine teeth in two oblique patches touching inner front edges of oval choanae; tongue notched posteriorly; single internal vocal sac.

Limbs slender; relative length of fingers is I <II <IV <III. Tips of all four fingers expanded into discs with circum-marginal and transverse ventral grooves; disc on finger I small, slightly wider than phalanx width; disc width shorter than tympanum width; relative width of discs is I <II <III <IV. Nuptial pad slight; fingers webbed at base, webbing formula is I2 –2.5II2–3.5III3– 2.5IV following Myers and Duellman (1982). Fringe of skin on edge of all fingers; subarticular tubercles prominent and rounded, formula 1, 1, 2, 2; supranumerary tubercles present; two metacarpal tubercles, outer slightly narrower than inner; row of white warts forming serrated fringe along outer edge of forearm.

Heels overlapping when legs at right angle to body; relative length of toes is I <II <V <III <IV. Tips of toes expanded into discs with circum-marginal and transverse ventral grooves; toe discs smaller than finger discs; disc on toe I same with width as phalanx width; relative size of discs is I <II <III <IV <V. Webbing moderate on all toes, webbing formula is I2 –2.5II1.5–3III1.5–3IV2.75– 1.5V. Subarticular tubercles prominent and rounded, formula 1, 1, 2, 3, 2; supernumerary tubercles absent; inner metatarsal tubercle distinct, oval; outer metatarsal tubercle absent; series of tubercles forming serrated dermal fringe along outer edge of tarsus and fifth toe.

Numerous small or large tubercles scattered on top of head, upper eyelids, dorsum, and flanks; patch of white tubercles below vent; white conical tubercle on tibiotarsal articulation; throat and chest finely granulated and abdomen coarsely granulated; dorsal surface of limbs tuberculate and ventral surface of thighs finely granulated.

Color of holotype in life.

Iris golden brown; dorsal surface grayish brown with dark brown saddle-shaped mark on dorsum, beginning behind eye; dark brown inverted triangle-shaped mark between eyes; lateral head and tympanic region brown with dark brown spot below canthus; broad dark brown bar along canthus rostralis; limbs dorsally brown with clear dark brown barring; rear, anterior, and venter of thigh light yellow with scattered brown spots, more spots on rear; rear of flank faint yellow with brown spots; chest and abdomen white, nearly immaculate; chin clouded with black.

Color of holotype in preservative.

In preservative (Fig. 4), dorsal ground color brown, pattern same as in life. Chest and abdomen white; chin clouded with dark brown; flank dirty white with dark brown spots; rear, anterior, and venter of thigh dirty white with scattered brown spots, more so on rear.

Variations.

Morphometric data are summarized in Table 4. Because the holotype and paratypes of the new species are all male, sexual dimorphism could not be determined. Differing from the nearly immaculate abdominal surfaces of the holotype and paratypes from the type locality, abdominal surfaces of three paratypes (KIZ 170183Y, 170184Y, 170186Y) from Yangjiatian, Gejiu are scattered with fine brown spots (Fig. 7). TL is longer than FL in the holotype and most paratypes, but TL is shorter than FL in paratype KIZ 170182Y (Table 4). Additionally, pattern of dark brown mark on dorsum varies among specimens. The holotype and most paratypes have a saddle-shaped dorsal mark, but the two paratypes KISD 1506203 and KISD 1506204 have an X-shaped dorsal mark and the paratype KIZ 170183Y has no obvious dark brown mark on dorsum.

Ecology.

At present, the new species is known only from the type locality, Lenquan Village, Mengzi City, Yunnan Province and Yangjiatian Village, Gejiu City, Yunnan Prov ince (Fig. 1). The holotype was found calling on a tree branch approximately 0.5 m above near a dry puddle in a fruit garden in Lenquan Village (Fig. 8). All other specimens were found on vegetation near the dry puddle in Lenquan Village or vegetation near a reservoir in Yangjiatian Village. Males began to call at about 19:30 when sky was getting dark and all specimens were encountered at night (20:00-22:45). Males called loudly, but no females or eggs were found. Hyla annectans (Jerdon, 1870), Kaloula verrucosa Boulenger, 1904, and Microhyla heymonsi Vogt, 1911 were also encountered at the type locality.

Comparisons.

The new species, Kurixalus lenquanensis sp. n., is morphologically similar to K. idiootocus in that it has a small body size (mean male SVL of 27 mm in new species versus mean male SVL of 27.5 mm in K. idiootocus ; Table 5). However, the new species can be distinguished from K. idiootocus by its obtusely pointed snout with no prominence on tip, absence of a pair of symmetrical large dark patches on chest, single internal vocal sac, and absence of supernumerary plantar tubercles (versus pointed snout with a small prominence on tip, presence of a pair of symmetrical large dark patches on chest, single external vocal sac, and small supernumerary plantar tubercles; Kuramoto and Wang 1987; Figs 9-10). In addition, besides that snout of the new species is shorter than that of K. idiootocus , the PCA analysis showed that the new species also differs from K. idiootocus by greater ratio of FL divided by SVL (Table 3 and Fig. 3).

Kurixalus lenquanensis sp. n. is distinguished from K. berylliniris by gold brown iris, obtusely pointed snout with no prominence on tip, smaller body size, tubercles on upper eyelid, slight nuptial pad, and coarsely granular abdomen (versus emerald to light green iris, pointed snout with a small prominence on tip, larger body size [mean SVL in males = 35 mm], lack of palpebral tubercles, greatly expanded nuptial pad, and smooth abdomen; Wu et al. 2016; Fig. 10).

In addition, the new species can be distinguished from K. wangi by a lack of prominence on snout tip, smaller body size, presence of tubercles on dorsum, coarse skin on flanks, and slight nuptial pad (versus pointed snout with small prominence on tip, larger body size [mean SVL in males = 30 mm], absence of tubercles on dorsum, smooth skin on flanks, and greatly expanded nuptial pad; Wu et al. 2016; Fig. 10) and from K. eiffingeri by smaller body size, slight nuptial pad, oblique loreal region, and curved canthus rostralis (versus larger body size [mean SVL of 31.1 mm in males], greatly expanded nuptial pad, vertical loreal region, and straight canthus rostralis; Wu et al. 2016).

Kurixalus lenquanensis sp. n. further differs from Kurixalus appendiculatus ( Günther, 1858) by smaller body size, absence of dermal prominence on snout tip, and tympanum less than half of eye diameter (versus larger body size [male SVL = 30-37 mm], presence of prominence on snout tip, and tympanum half eye diameter; Günther 1858, Inger et al. 1999); from K. baliogaster by smaller body size (SVL in males = 25.0-27.4 mm), absence of prominence on obtusely pointed snout tip, absence of large dark spots on ventral surface, tuberculated dorsal and lateral skin, presence of tubercles on eyelids, granular throat, and presence of dermal fringes on limbs (versus larger body size [male SVL = 33.0-33.3 mm], pointed snout with prominence on tip, large dark spots on ventral surface, smooth dorsal and lateral skin, absence of tubercles on eyelids, smooth throat, and absence of dermal fringes on limbs; Inger et al. 1999); and from Kurixalus banaensis (Bourret, 1939) by smaller body size, obtusely pointed snout being shorter than eye, presence of vomerine teeth, and tuberculate flanks (versus larger body size [mean SVL in males = 29.7 mm], markedly pointed snout being longer than eye, absence of vomerine teeth, and smooth flanks in K. banaensis ; Nguyen et al. 2014a, Nguyen et al. 2014b, Bossuyt and Dubois 2001).

The new species differs from Kurixalus viridescens Nguyen, Matsui, & Duc, 2014 by tuberculate dorsum, brown dorsal color, dark bands on dorsum and limbs, brownish clouded pattern on chin, and presence of vomerine teeth (versus nearly smooth dorsum, uniformly greenish dorsal color, no dark markings on dorsum and limbs, pinkish cream without marking on chin, and absence of vomerine teeth in K. viridescens ; Nguyen et al. 2014b); from Kurixalus ananjevae (Matsui & Orlov, 2004) by smaller body size, presence of vomerine teeth, presence of dermal fringes on limbs, and finely granular throat surface (versus larger body size [32 mm in one male], absence of vomerine teeth, absence of dermal fringes on limbs, and smooth throat surface; Matsui and Orlov 2004); and from Kurixalus motokawai Nguyen, Matsui, & Eto, 2014 by obtusely pointed snout tip, presence of vomerine teeth, and clouded chin with brown (versus pointed snout tip, absence of vomerine teeth, and small dark brown spots scattered on chin; Nguyen et al. 2014a)

Currently, two species of Kurixalus ( K. bisacculus and K. odontotarsus ) are recognized in Yunnan, China ( Yu et al. 2010). The new species can be distinguished from K. bisacculus and K. odontotarsus by smaller body size, absence of large black spots on belly, and obtusely pointed snout with no prominence on tip (versus larger body size [mean SVL in males at more than 33 mm], presence of large black spots on belly, and markedly pointed snout with a prominence on tip extending beyond lower jaw in K. bisacculus and K. odontotarsus ; Table 5; Fig. 9). Moreover, the PCA analysis revealed that the new species further differs from K. odontotarsus and K. bisacculus by smaller ratio of SL/SVL, smaller ratio of DNE/SVL, and bigger ratio of FL/SVL (Table 3 and Fig. 3).

Additionally, the new species differs from K. verrucosus found in Myanmar by smaller body size, snout shorter than diameter of eye, interorbital distance wider than upper eyelid, tympanum less than half of eye diameter, moderate toe webbing, granular throat and chest, and absence of large brown spots on belly and throat (versus larger body size [mean SVL in males = 29.9 mm], snout as long as diameter of eye, interorbital space as broad as upper eyelid, tympanum half eye diameter, nearly entirely developed toe webbing, smooth throat and chest, and presence of large brown spots on belly and throat; Boulenger 1893); and from Kurixalus naso (Annandale, 1912) by smaller body size, obtusely pointed snout with no dermal prominence on tip, moderately developed toe webbing, and absence of large dark spots on chest and belly (versus larger body size [male SVL at more than 30 mm], pointed snout with a dermal prominence on tip, almost completely developed toe webbing, and presence of large dark spots on chest and belly in K. naso ; Annandale 1912, Mathew and Sen 2008).