Nidirana mangveni Lyu, Qi, & YY Wang, 2020

Lyu, Zhi-Tong, Dai, Ke-Yuan, Li, Yao, Wan, Han, Liu, Zhe-Yi, Qi, Shuo, Lin, Si-Min, Wang, Jian, Li, Yu-Long, Zeng, Yang-Jin, Li, Pi-Peng, Pang, Hong & Wang, Ying-Yong, 2020, Comprehensive approaches reveal three cryptic species of genus Nidirana (Anura, Ranidae) from China, ZooKeys 914, pp. 127-159 : 127

Nidirana mangveni Lyu, Qi, & YY Wang sp. nov. Figures 8 , 9 , 10

Chresonymy.

Nidirana adenopleura : Fei et al. 2009, 2012

Holotype.

SYS a006313 (Figs 8 , 9 ), adult male, collected by Jian Wang and Zhao-Chi Zeng on 1 August 2017 from Mt Dapan (28.9801°N, 120.5447°E; ca 860 m a.s.l.), Pan’an County, Zhejiang Province, China.

Paratypes.

Eight adult specimens. Males SYS a006311-12, SYS a006314/ CIB 107275, and female SYS a006310, collected by Jian Wang and Zhao-Chi Zeng at the same time from the same locality as the holotype; males SYS a006413-14 and female SYS a006416, collected by Jian Wang and Zhao-Chi Zeng on 3 August 2017 from Mt Longmen (29.8643°N, 119.9790°E; ca 540m a.s.l.), Fuyang District, Hangzhou City, Zhejiang Province, China; male SYNU 12050569 collected by Zheng-Yan Zhou on 8 May 2012 from Hangzhou Botanical Garden (30.2544°N, 120.1226°E; ca 100m a.s.l.), Xihu District, Hangzhou City, Zhejiang Province, China.

Etymology.

The species name mangveni refers to Professor Mangven L. Y. Chang (= Meng-Wen Zhang, 张孟闻), an outstanding zoologist born in Ningbo City of northern Zhejiang, who contributed mostly on Chinese herpetological taxonomy and natural history. He is also the author of Nidirana daunchina , a congener of this new species.

Differential diagnosis.

Nidirana mangveni sp. nov. is distinguished from its congeners by the following combination of the morphological characteristics: (1) body large and elongated, with SVL 53.6-59.7 (56.2 ± 2.5, N = 7) mm in adult males, and SVL 62.4 ± 3.8 (59.7-65.1, N = 2) mm in adult females; (2) disks of digits dilated, rounded; (3) lateroventral grooves present on fingers III and IV, and each toes; (4) relative finger lengths I <II <IV <III; (5) heels overlapping; (6) tibio-tarsal articulation reaching the anterior corner of eye; (7) week supratympanic fold present; (8) mid-dorsal stripe absent or present on posterior dorsum; (9) posterior of dorsal skin rough with dense tubercles; (10) developed supernumerary tubercles below the base of each finger, palmar tubercles prominent and distinct; (11) white horny spinules on the posterior or entire dorsum in males; (12) a pair of subgular vocal sacs present; (13) one single nuptial pad present on the finger I, nuptial spinules invisible; (14) suprabrachial gland large; (15) calling: 2-7 identical regular notes.

Comparison.

Morphologically, Nidirana mangveni sp. nov. is unique when compared with all recognized congeners by the combination of the following characteristics: (1) large body size, SVL 53.6-59.7 mm in males and 59.7-65.1 mm in females vs. <53.0 mm in males or females in N. nankunensis , N. okinavana , N. daunchina , N. yaoica , N. chapaensis and N. hainanensis ; (2) relative finger lengths I <II <IV <III vs. II <I = IV <III in N. chapaensis ; vs. II <IV <I <III in N. leishanensis ; vs. II <I <IV <III in all other congeners; (3) absent of lateroventral groove on fingers I and II vs. absent on fingers and toes in N. pleuraden ; vs. absent or barely visible on fingers in N. daunchina ; vs. present on finger II in all other congeners; (4) tibio-tarsal articulation reaches at the anterior corner of eye vs. beyond the snout tip in N. lini ; vs. at the nostril in N. guangdongensis , N. nankunensis , N. daunchina , N. yaoica , N. chapaensis and N. hainanensis ; (5) week supratympanic fold present vs. absent in N. guangdongensis , N. adenopleura , N. nankunensis , N. daunchina , N. yaoica , N. hainanensis , and N. lini ; (6) white horny spinules on the posterior or entire dorsum in males vs. absent on dorsum or few above vent in N. nankunensis , N. okinavana , N. daunchina , N. yaoica , N. chapaensis , N. leishanensis and N. hainanensis ; (7) the presence of a single nuptial pad on finger I vs. absent in N. hainanensis ; vs. divided into two parts in N. chapaensis ; vs. two nuptial pads on fingers I and II respectively; (8) the presence of a pair of subgular vocal sacs vs. absent in N. okinavana .

Description of holotype.

SYS a006313 (Figs 8 , 9 ), adult male. Body large and elongated, SVL 54.0 mm; head longer than wide (HDW/HDL 0.87), flat above; snout rounded in dorsal and lateral views, slightly protruding beyond lower jaw, longer than horizontal diameter of eye (SNT/ED 1.22); canthus rostralis distinct, loreal region concave; nostril round, directed laterally, closer to the snout than to the eye; a longitudinal swollen mandibular ridge extending from below nostril through lower edges of eye and tympanum to above insertion of arm, where the ridge is intermittent, forming a maxillary gland and shoulder gland; week supratympanic fold present; interorbital space flat, narrower than internasal distance (IND/IOD 1.25); pupil elliptical, horizontal; tympanum distinct, round, TD/ED 0.73, and close to eye, TED/TD 0.31; pineal ocellus present; vomerine ridge present, bearing small teeth; tongue large, cordiform, notched behind; a pair of subgular vocal sacs present.

Forelimbs moderately robust, lower arm 0.18 of SVL and hand 0.26 of SVL; fingers thin, relative finger lengths I <II <IV <III; tip of each finger slightly dilated, forming rounded disks; lateroventral grooves on fingers III and IV, not meeting at the tip of disks; fingers free of webbing; presence of distinct lateral fringes on inner and outer sides of fingers II, III and IV, absent on finger I; subarticular tubercles prominent and rounded; developed supernumerary tubercles below the base of each finger; three elliptic, large, prominent and very distinct palmar tubercles; a single nuptial pad on the dorsal surface of first finger, nuptial spinules invisible.

Hindlimbs relatively robust, tibia 0.52 of SVL and foot 0.76 of SVL; heels overlapping when hindlimbs flexed at right angles to axis of body; tibio-tarsal articulation reaching the anterior corner of eye when hindlimb is stretched along the side of the body; toes relatively long and thin, relative lengths I <II <V <III <IV; tip of each toe slightly dilated with remarkable elongated ventral callous pad, forming long and pointed disk; well-developed lateroventral grooves on toes, not meeting at the tip of disks; webbing moderate, webbing formula: I 1½ - 2⅓ II 1⅓ - 2⅓ III 1½ - 3 IV 3⅓ - 1⅔ V; presence of lateral fringes on inner and outer sides of each toes, forming distinct dermal flap on the lateral edges of toes I and V; subarticular tubercles rounded, prominent; inner metatarsal tubercle elliptic, length triple the width; outer metatarsal tubercle indistinct, small and rounded; tarsal folds and tarsal tubercle absent.

Dorsal skin of head and anterior body smooth, posterior dorsum of body rough with dense tubercles with horny spinules; week intermittent dorsolateral fold from posterior margin of upper eyelid to above groin; upper flank with sparse tubercles; a large and smooth suprabrachial gland behind base of forelimb, not prominent; dorsal surface of upper arm smooth with sparse tubercles without spinules; the dorsal surfaces of thigh and tibia relatively rough with several weak longitudinal ridges and tubercles bearing spinules. Ventral surface of throat, body, and limbs smooth; large flattened tubercles densely arranged on the rear of thigh and around vent.

Coloration of holotype.

In life (Fig. 8 ), dorsal surface brown; pineal ocellus yellowish; mid-dorsal stripe unclear; dorsolateral fold dark brown; upper flank olive brown; lower flank creamy white; suprabrachial gland white. Dorsal limbs brown; a longitudinal black stripe on the anterior surface of the forelimb; three dark crossbars on the thigh, three on the tibia and three on the tarsus. Loreal and temporal regions dark, tympanum light brown; upper ⅓ iris brownish white and lower ⅔ iris reddish brown; maxillary gland and shoulder gland white. Throat white tinged with pink, but two subgular vocal sacs flesh colored; ventral surface of body and limbs creamy white; rear thigh tinged with pink; ventral hand flesh colored; ventral foot brown.

In preservative (Fig. 9 ), dorsal surface became darker; mid-dorsal stripe unclear; white spinules more distinct; pineal ocellus more distinct; crossbars on limbs became clearer; flanks and ventral surface faded.

Variations.

Measurements of type series are given in Table 7 . All specimens were similar in morphology. Females (62.4 ± 3.8 mm, N = 2) (Fig. 10 ) are relatively larger than males (56.2 ± 2.5 mm, N = 7), and more smooth than males. Pineal ocellus invisible in SYS a006310, 6311; dorsal surface light brown in SYS a006310, 6311; a short mid-dorsal stripe on the posterior dorsum in SYS a006311, 6416; spinules on the entire dorsum in SYS a006413.

Distribution and ecology.

Currently, Nidirana mangveni sp. nov. is known from Mt Dapan, Mt Longmen, and Hangzhou Botanical Garden, all situated in northern Zhejiang, suggesting the Nidirana populations in northern Zhejiang might belong to this species. This frog inhabits natural or artificial swamps, ponds, and paddy fields. The adult males do not construct nests and calls at the water surface or the bank from May to August. The male individual SYNU12050569 which was found in early May bears indistinct nuptial pads but processes the suprabrachial gland, indicating the breeding season of this species begins from early May. The tadpoles of this species remain unknown.

Vocalization.

The advertisement call (N = 108) of Nidirana mangveni sp. nov. contains 2-7 repeated, identical, regular notes. The three-note call has a duration of 515.0-741.0 (684.0 ± 50.9, N = 26) ms; the four-note call has a duration of 722.5-1044.6 (907.0 ± 82.9, N = 40) ms; the five-note call has a duration of 898.1-1341.7 (1087.1 ± 108.5, N = 20) ms; the six-note call has a duration of 1332.0-1427.0 (1377.9 ± 26.4, N = 15) ms. The notes last 89.0-203.0 (136.9 ± 23.2, N = 462) ms with the rise time 4.1-148.6 (79.5 ± 26.9, N = 462) ms, and the intervals last 59.3-192.7 (116.4 ± 20.8, N = 354) ms.

Figures

Figure 8. Morphological features of the adult male holotype SYS a 006313 of Nidirana mangveni sp. nov. in life. (A) dorsolateral view; (B) ventral view; (C) right hand; (D) left foot; (E) close-up of head showing the week supratympanic fold; (F) close-up of posterior dorsum and hindlimb showing the horny spinules.

Figure 9. Morphological features of the adult male holotype SYS a 006313 of Nidirana mangveni sp. nov. in preservative. (A) dorsal view; (B) ventral view; (C) lateral view; (D) right hand; (E) right foot.

Figure 10. (A), (B), and (C) dorsolateral view, ventral view, close-up of head showing the week supratympanic fold of adult female paratype SYS a 006310 of Nidirana mangveni sp. nov.; (D) adult female paratype SYS a 006416.