An Australian Ant of the Genus Leptothorax Mayr

Leptothorax is supposed to. have a cosmopolitan distribution, if we except Australia, Papua and New Zealand, from which no species of this large genus has ever been described. A few species range well up into the north temperate zone, both in North America and Eurasia, while others occur as far south as southern Brazil, the Cape of Good Hope and Sumatra. Several subgenera have been recognized but one is inclined to agree with Emery that the characters on which they are based are rather illusive and unimportant. Furthermor.e, Leptothorax is not sharply differentiated in tropical America from the genus Macromischa Roger. It now appears that Leptothorax is represented in the Australian fauna by at least one species. The late Mr. A. M. Lea of Adelaide, South Australia, sent me many years ago a large, miscellaneous collection of ants which he made in various parts of the island continent. Among the specimens, two. workers which he took in the Cairns District, Queensland, unquestionably belong to the genus Leptothorax and combine the elongate petiolar peduncle of a group of species (rottenbergi group of Emery), peculiar to the Mediterranean Region, with the epaulate pronotum of the subgenus Goniothorax, to which Emery has assigned the Ethiopian, South African, Malagasy, Sumatran and Neotropical species. Since, however, a similar’ combination of characters occurs in at least one South African Leptothorax (L. (G.) ltinodis Mayr) I am placing the Australian ant in the subgenus Goniothorax.