Phylogenetic relationships of Oraseminae (Hymenoptera : Eucharitidae)

Old World Oraseminae were revised recently and. a phylogeny proposed; howev er, nothing was known at that time about the biology or immature stages for genera other than Orasema. The immature stages, habits, and host associati ons of Timioderus and Orasemorpha are herein described, and a new species o f Orasema, O. monomoria, is described based. on material reared from a spec ies of Monomorium (Formicidae: Myrmicinae) in Madagascar. Using this new in formation, the relationships of Old World Oraseminae were reanalyzed. After successive weighting of 48 trees, a set of six trees (length 191, retentio n index 0.80) was found, that matched the earlier hypothesis. To better eva luate behavioral traits of Oraseminae, nine species groups of Orasema from the New World were characterized and included in a separate analysis, resul ting in 54 successively weighted trees (length 204 steps, retention index 0 .81). Results suggest that a host shift to Pheidole (Myrmicinae) and intern al parasitism of the host larva by the first-instar larva, with a later shi ft to external parasitism of the pupa, are derived for Oraseminae. All Oras eminae deposit eggs into punctures formed. in the plant tissue by the ovipo sitor, but the habit of laying single eggs is plesiomorphic for Orasema and laying multiple eggs is derived for Orasemorpha and Timioderus. The use of an intermediate host for gaining access to the ant host appears to have be en derived. twice within Oraseminae.