Pukapuka Atoll, Cook Islands

April 2004. Assistance was requested with the identification of insects from Pukapuka Atoll, Cook Islands.

The following were suggested, but need confirmation:

1. Chalcid
2. ?Sapromyzidae
3. Asilidae
4. Dolichopodidae

1. ?Ephydridae/Agromyzidae
2. Tribe CLYTINI – named in New Zealand collection
3. Chironomidae

The parasite was thought to be Aprostocetus (Tetrastichodes) hagenowii (Ratzeburg). Diagnostic characters include: mesoscutum uniformaly covered with setae; fore coxa dark, hind coxa yellow; first segment of hind tarsus long – about 1.5 times longer than second segment. This species is known from tropical and subtropical regions throughout the world. It is a parasitoid of cockroach oothecae (primarily Periplaneta, Blatta and Blatella), and rarely as a hyperparasite on Evania appendigaster. Further information is given by Graham (1987) Bull. Brit. Mus. Nat. Hist, Ent., 55: 1-392 – p.89-91). Graham treated the genus Tetrastichodes (which contains hagenowii) as a subgenus of Aprostocetus. Biological information on this species is summarised by LeBeck (1991) Entomophaga 36: 335-352). Check the Universal Chalcidoidea Database website by John Noyes for information, references http://www.nhm.ac.uk/entomology/chalcidoids/.