Myrmecina ryukyuensis

Japanese Name

Kogata-kadofushi-ari

Terayama, M. (1996) Taxonomic studies of the Japanese Formicidae, part 2. Seven genera of Ponerinae, Cerapachyinae and Myrmicinae. Nature and Human Activities, 1, 9-32.

Total length of workers around 2 - 2.5 mm. General body color black; mesopleuron, petiole, mandibles, clypeus and antennae reddish brown; legs yellowish brown. Eyes small, each consisting of around 5 facets; the longest diameter shorter than the length of the 10th antennal segment. Bases of antennal scapes simple in structure, without covering lamellae. Median process on anterior margin of clypeus low. Propodeal spines directed backwards, each longer than its width. Subpetiolar process variously developed, but generally directed forwards. Head and mesosoma longitudinally rugulose, but the rugulae somewhat slender and obscure, their interspaces punctate; the spaces between the eyes and the ventral extensions of the longitudinal carinae extending from the occipital region punctate.

Although the species is distributed in the Nansei Islands, specimens from the Sakishima Group are slightly different from those collected on Amai-oshima I. and Okinawa I., in having smaller body size, less intense sculpturation, and smaller eyes. These differences need to be assessed as to whether they indicate infraspecific variation or the presence of several species. Found on the floor of broadleaf forests nesting under stones.

Nansei Is (Amami-oshima I., Okinawa I., Miyako I., Ishigaki I., Iriomote I., Yonaguni I.).