A new species of copepod (Siphonostomatoida: Caligidae) parasitic on the tiger shark Galeocerdo cuvier (Péron & Lesueur) from Western Australian waters.

A new species of sea-louse (Caligidae, Siphonostomatoida), Caligus oculicola n. sp., is described from the eye surface of the tiger shark Galeocerdo cuvier from off the northwestern coast of Australia. This copepod is distinguished from its congeners by a combination of characters that include: (i) a bifid, dentiform process of the maxillule; (ii) a sternal furca with a box longer than wide and diverging, truncate tines; (iii) terminal spines 1 to 3 on the last segment of leg 1 exopod, each with serrate margins and an accessory process (accessory process on the spines extending beyond the tip of the spine itself); and (iv) a two-segmented exopod of leg 4 with an armature formula of I-0; III. This is the first description of a caligid copepod collected from a shark host in Western Australian waters. The host-parasite relationships between Caligus oculicola and its elasmobranch host are discussed.