DECLINING FROGS OF THE WET TROPICS

Waterfall Frog/Torrent Frog (Litoria nannotis)

STATUS:

ENDANGERED; WELL PROTECTED. Declines in populations have been noted since 1990, from upland sites above 300 metres altitude.

DISTRIBUTION:

Found throughout the WTBR between Paluma and Cooktown.

HABITAT:

Fast flowing rocky streams in rainforest and wet sclerophyll forest at altitudes between 180 and 1300 metres. Usually found perched on boulders beside or behind waterfalls. Sometimes found perched on trees or leaf litter beside rocky streams.

DESCRIPTION:

Adult body length 45 - 65 mm. Dorsal surface with scattered tubercles; dull brown, slate or yellowish olive with irregular dark markings. No dorso-lateral skin fold present. Ventral surface granular. Ventral surface of males cream; throat dusty brown. Ventral surface of females cream, throat and ventral surface of thigh heavily pigmented with brown. Finger and toe discs large. Fingers with basal webbing, toes nearly fully webbed. Males with large black spinulated nuptial pad on proximo-dorsal side of thumb and accessory black-tipped spinules on upper chest. Prominent inner, small outer metatarsal tubercle. Tip of snout bluntly rounded. Tympanum indistinct.

CALL:

A repeated "crawk crawk crawk"; or a gentle, popping, slow growl-like sound, rarely heard above the sound of rushing water.

BREEDING AND LARVAE:

Eggs unpigmented, deposited in gelatinous egg mass under rocks in stream. Tadpoles grey/olive green. Tail musculature with scattered irregular dark or light grey flecks and blotches. Fins with slight dark and light grey flecks and blotches; faint venation. Sometimes dark pigmentation outlines posterior of tail fins. Intestine not visible, entirely covered by silver chromatophores. Branchial region partially visible. Silver chromatophores extend medially over branchial region covering half to two thirds. Oral disc completely surrounded by marginal and submarginal papillae. Submarginal papillae on upper labium anterior to row A- 1 in two or more complete, offset rows. Labial Tooth Row Formula: 2/3. Mouth suctorial, adapted for fast flowing water. Found predominantly in fast flowing sections of the stream, attached to rocks. Total length of tadpole up to

REFERENCES:

Description: Liem, 1974. Call: Liem 1974; McDonald, 1992. Larvae: Liem, 1974; Richards 1992. Miscellaneous: Dennis and Trenerry, 1984; Cogger, 1988; McDonald, 1991, 1992; Richards and James, 1992; Covacevich and McDonald, 1993; Richards et al, 1993; Trenerry et al., 1994.

Prepared by: J-M. Hero, Updated August 1, 1994. Dept. Zoology, James Cook University, QLD 4811.

zljmh@jcu.edu.au