The Australian species of the genus Ibacus (Crustacea: Decapoda: Scyllaridae), with the description of a new species and addition of new records

A new species of scyllarid lobster, Ibacus chacei, from eastern Australia is described and illustrated. The new species can be distinguished from all other known Ibacus species by the shape of the third maxilliped. Ibacus brevipes Bate, 1888 is recorded from Australia for the first time. Seven out of the eight known species of Ibacus are now recorded from Australia. Colour descriptions, and updated distributions for all Australian Ibacus species are included, plus further comments on the type locality of Ibacus peronii Leach, 1815. Colour illustrations and a key to the eight known species of Ibacus are also provided.