Lasius plumopilosus

This subterranean ant nests under stones. Very little is known of this rarely-collected species. It is thought to be a social parasite of the social parasite Lasius claviger. Although such social hyperparasitism is rare among ants, it does occur among other European and Asian Lasius species. (Ellison et al., 2012)

Identification
All species in the claviger group smell like citronella when disturbed or crushed. The feather-tipped plumose hairs on the gaster and small body size of all castes of L. plumopilosus make this ant unmistakable.

Distribution
Lasius plumopilosus is an uncommon, patchily distributed species that has been collected from Iowa, Michigan, Minnesota, North Carolina, and Long Island. It has not yet been collected from New England, but based on its general habitat and distribution, it could occur in Connecticut, Rhode Island, Cape Cod, or the Massachusetts Islands. (Ellison et al., 2012)

Distribution based on Regional Taxon Lists
Nearctic Region: United States.

Biology
The type nest was under a stone on a hillside. Another colony from the type locality was collected from a stage 3 log in a basswood-maple forest. The North Carolina collection was from a rotten stump. Queens and males of the type series were collected on Sept. 13; those from North Carolina were taken sometime during August. Flights may occur during both of these months. Collections of mixed colonies are lacking for plumopilosus, yet the small size and peculiar hairs of the queens strongly suggest that they are parasites. (Wing 1968)

Nomenclature

 *  plumopilosus. Lasius (Acanthomyops) plumopilosus Buren, 1941: 231, fig. 1 (w.q.m.) U.S.A. Combination in Acanthomyops: Creighton, 1950a: 433; in Lasius: Ward, 2005: 13. See also: Wing, 1968: 132.

Worker
Wing (1968) - Standing body hairs fairly numerous, many with moderately plumose tips. Pubescence more or less sparse, body shining. Body and appendages yellow to brownish yellow.

Queen
Wing (1968) - Standing body hairs numerous, mostly with strongly plumose tips. Pubescence moderately sparse, body shining. Body color brown, legs lighter.

Male
Wing (1968) - Standing body hairs moderate to sparse, a few of which have weakly plumose tips and are confined chiefly to occiput and dorsum of alitrunk. Pubescence sparser than in the female castes, cuticle finely sculptured, body surface only moderately shining. Body color very dark brown, almost black.

Hybrids
Wing (1968) described a hybrid form of this species.

Lasius subglaber × Lasius plumopilosus hybrid
A single sample collected by R. Sanwald in Selden, Suffolk Co., New York, August 1961, in sandy area.

Worker
Similar to subglaber in general appearance and size, but with standing body hairs much coarser, strongly barbulate, and pubescence on antennal scapes conspicuously suberect.

Crest of petiolar scale moderate, often faintly emarginate. Pubescence moderate to moderately dense over most of body and appendages, but that on posterior dorsum of gaster dilute. Color yellow to brownish yellow.

Queen
Resembles a small subglaber specimen with exceptionally low HW. Standing body hairs strongly barbulate, coarser, and a little more numerous than in subglaber. Dorsum of gaster with pilosity somewhat irregularly distributeq, but chiefly • confined to posterior edges of tergites.

Antennal scapes with pubescence loosely appressed to decumbent. Body and appendages with moderately dense pubescence except on posterior dorsum of gaster where it is fairly dilute. Crest of petiolar scale moderately blunt, not emarginate. Color brown, more or less like that of darker claviger queens.

Male
Unknown.

Type Material
Wing (1968) - Type locality: Backbone State Park, Delaware Co., Iowa. Location of types: Holotype female, : paratypes In several collections including the.