Rhacophorus tunkui Kiew, 1987

Ming, Leong Tzi, 2004, Larval Descriptions Of Some Poorly Known Tadpoles From Peninsular Malaysia (Amphibia: Anura), Raffles Bulletin of Zoology 52 (2), pp. 609-620 : 616-617

Rhacophorus tunkui Kiew, 1987

( Figs. 8-11 , Table 6)

Larval microhabitat. – A developmental series was reared from a freshly deposited clutch of ova (unpigmented), encountered on the night of 4 Jan.2003 within lowland forest at the Gunong Panti foothills (1 51’N, 103 23’E), south east Johor (coll. T. M. Leong et al.). The foam nest (ca. 8 x 4cm) was attached to the underside of a leaf of a shrub in the middle of a flooded pool (ca. 5 x 2m, 80cm deep). At this site, adult males were seen and heard calling from vegetation overhanging the pool, of which voucher specimens were obtained (ZRC.1.10363-10374). Other anurans found here were Polypedates macrotis , Rhacophorus appendiculatus , Kaloula baleata , Microhyla borneensis , M. palmipes . Attention was initially drawn to the foam nest by the presence of a juvenile keelback snake ( Xenochrophis trianguligerus ; ZRC.2.5623, total length 28.2cm), which was observed to be probing for ova and feeding from the foam nest ( Fig. 8 ). The leaf was carefully removed to allow further embryological development ex-situ, with initial signs of hatching after ca. 36 hours. The hatching embryos were allowed to drop into a receptacle of water placed ca. 30cm beneath ( Fig. 9 ).

Larval diagnosis. – A small tadpole (maximum TL ca. 30mm); body and tail grayish green in life; tail muscle with two to three closely spaced, dark spots (actually ocelli when viewed under microscope) along midline immediately posterior to body-tail junction; LTRF 6(2-6)/3.

Larval morphology. – ( Fig. 10 ) Body elliptical, BL 1.72-1.85 of BW, mildly depressed dorsoventrally, BH 0.75-0.81 of BW; snout rounded, nostril nearer to snout tip than eye; eyes dorsolateral, IOD 2.38-2.42 of IND; spiracle sinistral, continuous with body wall, oval opening directed upwards and backwards, spiracle visible from above and below, snout-spiracle 0.61-0.65 of BL; vent dextral, tubular, fused with ventral fin, opening directed towards posterior. Tail originating from body-tail junction, rising to slight convex at midpoint and gradually descending to rounded tip, dorsal fin slightly deeper than ventral fin, TAL 1.42-1.83 of BL, MTH 0.24-0.27 of TAL. Naso-lacrymal groove and lateral line pores present.

Colour/Markings. – In life, body and tail grayish green; greenish tinge increasingly pronounced in later stages; distinct spots (ocelli) on tail muscle black.

Oral Disc. – Marginal papillae on anterior labium confined to lateral corners, continuous row of marginal and single row of infra-marginal papillae on posterior labium; margin of upper jaw sheath curved, lower jaw sheath with ‘V’ arch, both jaw sheaths keratinised and serrated at their margins; ODW 0.47-0.52 of BW.

LTRF. – 6(2-6)/ 3 in advanced larvae, 5(2-5)/ 3 in earlier stages; size of labial teeth in P-3 smallest.

Developmental changes. – The diagnostic tail spots already show from an early stage but the full set of three only becomes obvious in later stages. In the emergent, the pale jade green colour is reminiscent of the adult colouration, and its flesh is translucent, enabling some of its limb bones to be seen ( Fig. 11 ). The red markings on the webbing of its hindfeet are not developed as yet. The emergents did not exceed 11mm in SVL ( Table 6).

Figures

Fig. 8. In-situ ovophagy by a juvenile Xenochrophis trianguligerus (ZRC.2.5623, total length 28.2cm) on the freshly deposited ova (unpigmented) of Rhacophorus tunkui. Photographed by Andrew Tay (04 Jan.2003).

Fig. 9. Freshly hatched embryos of Rhacophorus tunkui dropping into receptacle of water provided for them below.

Fig. 10. Lateral (A) and dorsal (B) aspects of Rhacophorus tunkui larva (Stage 37). Note presence of three distinct dark spots on midline of tail muscle, immediately posterior to body-tail junction.

Fig. 11. Dorsal aspect of recent emergent of Rhacophorus tunkui (Stage 46).