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The amphibian fauna of Sri Lanka comprises 120 species, including 107 (~90.0%) endemic species. They belong to five families: Bufonidae, Dicroglossidae, Ichthyophiidae, Microhylidae, and Rhacophoridae. Based on distribution, we recognized five zoogeographic zones for them, Central Hills, Dry Zone, Knuckles Range, Lowland Wet Zone, and Rakwana Hills. Fifty three species were reported from the Central Hills (48 endemics [90.6%] and 42 [79.2%] threatened species). 47 species were recorded from the Lowland Wet Zone, including 36 (76.6%) endemics and 28 (59.6%) threatened species. The Knuckles Range had 25 species, of which, 19 (76.0%) were endemics and 15 (60.0%) are threatened species. 19 species were reported from Dry Zone including seven endemics (36.8%) and four threatened species (21.1%). Out of 29 species, which inhabited in the Rakwana Hills, 26 were endemics (~89.7%) including 24 (82.8%) threatened species. Species diversity along the elevational gradient was also observed with the highest species richness in the mid-elevational localities. Family Ichthyophiidae can be considered as the least studied family. Recent rediscoveries and studies have helped to reduce the number of extinct species from 21 to 18. It is speculated that some of the other extinct species have to be rediscovered or probably were misidentified as other species. About 90% of Sri Lankan amphibians occur in the regions with the highest human populations where there are established agricultural lands. Loss of habitats, competition due to anthropogenic species and invasive species, pollution (cause for malformations, parasites, and other diseases), and climate change appear to be major threats.

This study was aimed to develop captive breeding and nurture the young of stonesucker (Garra ceylonensis, Bleeker), a small threatened freshwater fish species endemic to Sri Lanka. Breeding of stonesucker was possible under indoor conditions without hormonal stimulation. They were single spawners having a fecundity of 562±176 eggs per fish (total length of 7.9±0.6 cm) with an egg size of 770–1877 μm. Duration of development stages were, egg to hatchling 36–48 h, hatchling to postlarva stage 3–4 days, postlarva to juvenile stage 5–64 days and adult stage in 300–365 days at 26–28°C. Juveniles exhibited bottom dwelling habit in 70–75 days. Postlarva fed with formulated feed exhibited the highest growth (P<0.05) compared with live diets, Artemia and microworm (Anguillula sp.). Although the juveniles revealed a significantly high growth performance (P<0.05) with swine liver diet up to day 45 compared with formulated feed and combination of detritus and plankton, formulated feed exhibited an increase in growth from day 50. Therefore, formulated feed could be used for rearing of postlarva and juvenile stages without any live feeds.

ABSTRACT. Fish represent a major source of animal protein in the Sri