Adetomyrma

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Adetomyrma

Scientific classification

Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Amblyoponinae
Tribe:	Amblyoponini
Genus:	Adetomyrma

Species

A. venatrix Bolton, 1995
A. sp. mad-01 (undescribed)

Adetomyrma is an endangered ^[1] genus of ants endemic to Madagascar. First described in 1993, the genus did not attract much scientific attention until the discovery of an entire colony in 2001.

Otherwise nondescript ants, Dracula ants are named after their unusual feeding habits; queens and workers practice a form of "nondestructive cannibalism", chewing holes into and feeding on the haemolymph (insect "blood") of the colony's own larvae. This behaviour is thought to represent a precursor to the social feeding behaviour typical of more derived ant species, which use their larvae to digest their food (with the larvae later regurgitating it for the adults — which are unable to digest their own food — to eat).

Dracula ants are also notable for their seemingly ancestral morphology; unlike other ants, which have two or three joints between the thorax and abdomen, Adetomyrma species have just one. This single joint may indicate the Dracula ant to be an evolutionary "missing link" between ants and wasps which have similar abdomens.

The colonies, the first of which was found in a rotting log, may contain as many as 10,000 workers, winged males and several wingless queens (unusual, as most ant queens are winged). The workers use venom to stun their prey which are brought back to the colony for the larvae to feed upon. The colour of the winged males, a darker orange than the workers, suggests they disperse by flying to other colonies before mating.

Larva haemolyph as a food source has been reported in one other genus (to which the Dracula ant is not closely related), Leptanilla. However, in Leptanilla the larvae secrete haemolymph from special glands; no incision is necessary.

[edit] References

^ Social Insects Specialist Group (1996). Adetomyrma venatrix. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 10 May 2006. Listed as Critically Endangered (CR B1+2c v2.3)