Vollenhovia emeryi

Japanese Name

Umematsu-ari

Wheeler, W.M. (1906) The ants of Japan. Bulletin of the American Museum of Natural History 22: 301-328.

Total length of workers around 2.5 mm. Body color reddish brown to dark brown; gaster darker; head with a blackish brown spot just above clypeus; legs yellowish brown. Head rectangular; head width/head length ratio 0.83. Mandibles with 6 or 7 teeth. Mesosoma flat in profile; metanotal groove weakly developed. Propodeum with dentiform processes; their apices acute. Subpetiolar process well developed, forming a large lamellate plate about 0.05 mm deep. Dorsal areas of head and mesosoma with many longitudinal rugae.

Vollenhovia emeryi has colonies of two types: Type 1 colonies are usually monogynous with alate females, the reproductive offspring of which are also alate females; Type 2 colonies are usually polygynous and have short-winged reproductive females, the reproductive female offspring of which are also short-winged. Type 1 colonies are found mainly in montain forests, nesting in decaying wood. Type 2 colonies are found in or near riverside forests, also nesting in decaying wood. These two colony types might represent two separate species, or might be products of genetic polymorphism within a single species, as suggested by Kubota (1984). We tentatively treat them here as conspecific, while indicating the need for further studies on their status. In both types the alate females and males hibernate within the nests. Vollenhovia nipponica is a parasite frequently found in Type 2 colonies of V. emeryi. This species is distributed from Hokkaido to Yaku Island. It has been recorded from Taiwan, but the record is questionable.

Hokkaido, Honshu, Shikoku, Kyushu, Yaku I., Kuchino-erabu I.