Colony composition and morphological caste differentiation between ergatoid queens and workers in the ponerine ant genusLeptogenysin the Oriental tropics

摘要

Colony composition and morphological caste differentiation between queens and workers were studied in 14Leptogenysspecies collected in Malaysia and Indonesia. Ten species had ergatoid queens and four species reproduced by mated workers without morphologically distinct queens. Colonies of most species having ergatoid queens were monogynous, however, polygyny was found in two species. In contrast, all four species which reproduced by mated workers (= gamergates) were polygynous. Degree of caste differentiation between ergatoid queens and workers was conspicuous inL. myops. In the other species, the head width of ergatoid queens was almost the same as in their conspecific workers, although, the abdomen was generally wider in ergatoid queens than in workers. The workers of ergatoid species have almost the same number of ovarioles as their queens except forL. myops, however, spermathecae were remarkably reduced in length or missing. All workers in the four species that reproduced with gamergates had spermathecae which were smaller than those of ergatoid queens.