Rhacophorus reinwardtii ( Schlegel, 1840 )

Fajri, Muhammad Ichsan, Tjong, Djong Hon & Hamidy, Amir, 2023, Identification and taxonomic status of a Sumatran population of Norhayati’s gliding frog (Anura: Rhacophoridae), Raffles Bulletin of Zoology 71, pp. 303-316 : 312

Rhacophorus reinwardtii ( Schlegel, 1840)

( Figs. 4B , 5 , 6A )

Hyla reinwardtii Schlegel, 1840: 105 , pl. 30 (figs. 1, 2, 4); Gasso Miracle et al., 2007: 44.

Hypsiboas reinwardtii Wagler, 1830: 200 .

Polypedates reinwardtii Siedlecki, 1909: 704 .

Rhacophorus reinwardtii Tschudi, 1838: 73 ; Dumeril & Bibron, 1841: 532; Dumeril et al., 1854: 403, pl. 89 (fig. 1); Gunther, 1858: 82; Boulenger, 1882: 88; Van Kampen, 1910: 43; Van Kampen, 1923; 264; Hamidy & Kurniati, 2015: 66 (appendix).

Material examined. One female ( MZB Amph 32626), two males ( MZUA 210115 , MZUA 210116 ), Mardingding , North Sumatra, Indonesia, 3.2360°N, 98.020417°E, 400 m asl, coll. M. Ichsan Fajri and Muhardika, 4 February 2020 .

Description of MZB Amph 32626. Morphometric measurements are in Table 3. (1) Head length 34% of SVL and width 34% of SVL; (2) Snout slightly pointed; (3) Canthus rostralis sharp; (4) Loreal slightly concave; (5) Nostrils not protuberant, closer to snout than to eye; (6) Eyes large, protuberant, shorter (9% of SVL) than eye-tosnout length (12% of SVL); (7) Tympanum distinct, and subcircular with diameter (6% of SVL), about two-third of eye diameter (9% of SVL); (8) Tympanum to eye distance (1% of SVL) about a quarter of tympanum diameter; (9) Supratympanic fold prominent.

(10) Forelimbs (20% of SVL) shorter than hands (31% of SVL); (11) Hands fully webbed except for the first finger with two phalanges free of webbing; (12) Webbing formula I 2 – 1 II 0 – 0 III 0 – 0 IV; (13) Relative finger lengths I<II<IV<III from shortest to longest; (14) Dermal fringe present along the edge of forearm; (15) Finger disc large with circummarginal and transverse ventral grooves; (16) Third finger disc (4% of SVL) slightly less wide than tympanum; (17) Subarticular tubercle between the penultimate and adjoining proximal phalange well developed and rounded; (18) Other subarticular tubercles present but indistinct; (19) Nuptial pad absent; (20) Prepollex prominent and oval; (21) Inner and outer palmar tubercles present, flat, and indistinct; (22) Supernumerary tubercles absent; (23) Hind limbs long; (24) Femur (46% of SVL) slightly shorter than tibia (54% of SVL); (25) Feet (49% of SVL) shorter than tibia; (26) Relative toe lengths I<II<III<V<IV from shortest to longest; (27) Feet fully webbed; (28) Dermal fringe present, extending around tarsus from the edge of the fifth toe to the heel, which has a slightly pointed flap; (29) Subarticular tubercles distinct and rounded; (30) Inner metatarsal tubercle present but indistinct; (31) Outer metatarsal and supernumerary tubercles absent; (32) Dorsal skin smooth; (33) Flanks, ventral, and lower surface of thighs coarsely granulated; (34) Dorsolateral fold absent; (35) Anal flap bilobed.

(36) Dorsal colour green with dark spots; (37) Colour of flanks orange with black and blue streak or spots; (38) Ventral colour orange or yellow, and mottled with black; (39) Webbing orange, partially covered with black and small blue spots and streaks on fingers II–IV and toes II–V ( Fig. 5 ).

Colour in preservation. The dorsal colouration is lavender. The green pigmentation turned lavender. The black pigmentation did not change. The orange pigment turned ivory white, while the blue pigment turned grey.

Natural history. In Mardingding, three individuals were found at night perched on tree branches. Neither tadpoles nor eggs were found. The location altitude is approximately 400 m asl.

Comparison. The Sumatran R. reinwardtii specimens have no morphological differences with the Javan population, with a hand webbing formula of I 2 – 1 II 0 – 0 III 0 – 0 IV, dorsal surface dark green with small dark spots, ventral surface orange with or without dark spots, flanks with dark pigmentation and blue streaks, and webbing colour yelloworange, black, with blue spots. Compared with R. reinwardtii var. lateralis , the specimens of Sumatran R. reinwardtii possessed more differences in morphological features such as less black pigmentation of flanks, presence of small black spots on dorsum (vs absence in R. reinwardtii var. lateralis ), less black colouration on webbing (vs dominantly black in R. reinwardtii var. lateralis ), and fewer black spots on ventral region and lower thighs ( Fig. 4 ). However, it is similar in having green dorsum colouration. The specimens also overlapped with the SVL range of the Javan population ( Table 4). Rhacophorus norhayatiae differs from R. reinwardtii in hand webbing formula I 1½ – 1 II 0 – 0 III 0 – 0 IV (vs I 2 – 1 II 0 – 0 III 0 – 0 IV in R. reinwardtii ), dorsum immaculate green (vs presence of dark spots in R. reinwardtii ), black demarcation on flanks extended from armpits to the thighs (vs flanks orange with black and blue streak or spots in R. reinwardtii ), presence of black spots on underside of thighs (vs absence in R. reinwardtii ), interdigital webbing black with blue spots or streaks (vs orange and partially covered with black, and small blue spots and streaks on fingers II–IV and toes II–V in R. reinwardtii ). Rhacophorus borneensis differs from R. reinwardtii in hand webbing formula I 1½ – 1½ II 0 – 0 III 0 – 0 IV (vs I 2 – 1 II 0 – 0 III 0 – 0 IV in R. reinwardtii ), dorsum green without spots or streaks (vs green scattered with black spots in R. reinwardtii ), black colouration on flanks is about half with yellow and blue spots (vs flanks orange with black and blue streak or spots in R. reinwardtii ), ventral surface yellowish-orange (vs orange sometimes scattered with black spots in R. reinwardtii ), and males have yellowish-orange posterior surface. Rhacophorus kio differs from R. reinwardtii by having a spine-like heel flap (vs absence in R. reinwardtii ), hand webbing formula I 1½ – 1 II 0 – 0 III 0 – 0 IV (vs I 2 – 1 II 0 – 0 III 0 – 0 IV in R. reinwardtii ), a dark green dorsum with white spots and greenish-white markings (vs green scattered with black spots in R. reinwardtii ), black pigmentation of flanks occurring as small black spot in the armpit (vs flanks orange with black and blue streak or spots in R. reinwardtii ), and webbing with a network of yellow-orange lines (vs orange and partially covered with black, and small blue spots and streaks on fingers II–IV and toes II–V in R. reinwardtii ), and having a larger SVL size ( Table 4). Rhacophorus helenae is distinguished from R. reinwardtii in having the webbing formula I 1½ – 1½ II 0 – 0 III 0 – 0 IV (vs I 2 – 1 II 0 – 0 III 0 – 0 IV in R. reinwardtii ), venter white without spots or marks (vs orange sometimes scattered with black spots in R. reinwardtii ), a bluish-green posterior surface of the thighs with pale yellow marbling (vs green in R. reinwardtii ), and a low, single-lobed supercloacal dermal ridge (vs absence in R. reinwardtii ), and having a larger SVL ( Table 4). Furthermore, R. nigropalmatus is distinguished from R. reinwardtii in having complete webbing (vs I 2 – 1 II 0 – 0 III 0 – 0 IV in R. reinwardtii ), dorsum green scattered with small white spots (vs green scattered with black spots in R. reinwardtii ), a white-yellowish ventral surface (vs orange sometimes scattered with black spots in R. reinwardtii ), and yellow colouration on the flanks with black veins (vs flanks orange with black and blue streak or spots in R. reinwardtii ), and having larger size of SVL ( Table 4).

Figures

Fig. 4. Comparison of black pigmentation on flanks between A, preserved Sumatran R. norhayatiae MZB Amph 32625 and B, R. reinwardtii MZB Amph 32626.

Fig. 5. Sumatran specimen of R. reinwardtii MZB Amph 32626. A, ventral view; B, dorsal view; C, dorsolateral view; D, webbing of hands. Scale = 10 mm.

Fig. 6. Comparison of dorsal view of webbings of A, R. reinwardtii, B, R. norhayatiae, and C, R. reinwardtii var. lateralis. The webbing colouration of R. reinwardtii var. lateralis is predominantly black which is most similar to R. norhayatiae rather than to R. reinwardtii. The figure of R. reinwardtii var. lateralis was modified from Werner (1900).