Polyergus samurai

Japanese Name

Samurai-ari

Yano, M. (1911) A new slave-making ant from Japan. Psyche 18: 110-112.

Polyergus rufescens subsp. samurai Yano 1911, Polyergus samurai: Emery, 1925,

Total length of worker about 7 mm. Body color somewhat brownish black. Antennal insertions situated adjacent to posterior margin of clypeus. Posterior border of head narrowed. Promesonotum not especially protrusive; spiracles of mesothorax conspicuously raised. Posterodosal portion of propodeum slightly angulate and raised.

This species much resembles its slave Formica japonica Motschoulsky in size and color, but is distinguishable by its slightly larger size, more blackish body colour and sickle-shaped mandibles (versus subtriangular in F. japonica). Formica japonica is its main slave, and sometimes F. sp. (hayashi). A colony comprising three species, with both F. fukaii Wheeler and F. japonica as slaves, has been observed on Mt. Zao, Miyagi Prefecture (Sonobe, unpublished); this seems to be a rare occurrence. P. samurai nests in the soil and is seldom seen on the ground except when slave-raiding. Raids are carried out at around 3 to 4 pm during summer, when cocoons of slave species are to be found. Hasegawa & Yamaguchi (1995) reported the detailed ecology and raiding behavior of this species. Less common in Shikoku and Kyushu than elsewhere. Nuptial flights occur around July. Chromosome number n = 27 (Crozier, 1970).

Hokkaido, Honshu, Shikoku, Kyushu; Mainland China, Korean Peninsula.