The bird-dropping spider (Ornithos catoides) in Johor
This brief note by H. N. Ridley reports the discovery of a species of the bird-dropping spider genus Ornithoscatoides on Gunong Panti in Johor, which he considers probably distinct from Forbes’ O. decipiens from Java and Sumatra (p. 173).
Summary
Ridley describes the spider’s remarkable mimicry of a piece of bird’s dung on a leaf, a behaviour previously documented by H. O. Forbes and the Rev. O. Pickard Cambridge in Wanderings of a Naturalist. The genus spins a thin web on a leaf to represent the watery portion of excreta, then lies on its back on the web, held by strong spines on the legs, to ambush butterflies that alight on the supposed dropping (p. 173). Ridley’s specimen had left its web—a thin circular white film on a wild plantain leaf—to feed on a captured red bug. On comparison with Forbes’ description, he notes differences in body colouring and several structural points, leading him to conclude it is likely a new species (p. 173).