Abstract
A detailed analysis of intraspecific morphological variation and sexual dimorphism was conducted for seven Nearctic species in the subgenus Gastrosema Fischer. Results from the analysis are presented as a complete description or redescription of each species. Two species of Nearctic Gastrosema recognized by Fischer (1977) are synonymized. Using knowledge of character stability gained through the analysis of intraspecific morphological variation, three previously unrecognized species groups are established. Each Nearctic species in Gastrosema is assigned to a species group, as well as the type species for Gastrosema. A discussion of Nearctic species in other subgenera that fall within the Gastrosema species groups is provided. A dichotomous key is presented to facilitate identification of Nearctic species in the subgenus Gastrosema treated by Fischer (1977) and two species previously unknown to science. Patterns of host utilization are assessed for species of Opius Wesmael attacking various species of Phytomyza Fallen mining the leaves of hollies. The results are presented as percentages of each parasitoid species reared from a particular host-host plant combination.
Kula, Robert R (2001). Revision of Neartic species in Opius (Gastrosema)(Hymenoptera:Braconidae:Opiinae). Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2001 -THESIS -K85.