Tetramorium atratulum

Tetramorium atratulum
T. atratulum male
Conservation status
Vulnerable  (IUCN 2.3)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Genus:	Tetramorium
Species:	T. atratulum
Binomial name
Tetramorium atratulum (Schenck, 1852)

Tetramorium atratulum is a rare workerless socially parasitic ant from the Palaearctic region, which has even been introduced together with its host in North America. This extreme inquiline is represented only by female and pupoid type male individuals, whose morphology and anatomy indicate a highly specialized level of parasitism. The body of males is depigmentated, the cuticle is thin, the petiole and postpetiole are widely connected, and degenerate mandibles, palps, and antennae are observed. Female wing venation is reduced and the occipital region is narrowed. Mature females are typically physogastric and found in queenless host nests.^[2]

Since, unlike many other obligate social parasites, T. atratulum is never known to coexist with the host colony's fertile queen, every T. atratulum–Tetramorium sp. colony is doomed to survive only the lifespan of the youngest Tetramorium sp. workers. Thus, the parasitic queen has very limited scope for producing alates to secure the next generation, as this time span is often only 2–3 years or fewer. As a result, even within its well-established range, T. atratulum is very scarce, with only a tiny proportion of Tetramorium sp. colonies playing host to this parasite.^{[citation needed]}