|dc.description.abstract||This work is directed at defining and elucidating some of the basic problems in the phylogenetic classification of the Opomyzoidea. (chapter 1).
In chapter 2, I present a quantitative phylogenetic analysis of the Asteioinea (Opomyzoidea). The ingroup and outgroup samples accommodate differing hypothesis of relationships by authors since Hennig. A total of 49 exemplar species and 123 morphological characters are analyzed under six combinations of character coding and weighting methods. The results support the monophyly of the Opomyzoidea and Asteioinea sensu J. F. McAlpine (1989), with the exception that the Odiniidae is separated from the Opomyzoidea by several outgroup nodes. The outgroup consistently nearest the Opomyzoidea is the family Chyromyidae (Sphaeroceroidea). Within Asteioinea, Asteidae + Xenasteidae are consistently grouped with Aulacigastridae, and Neminidae + Neurochaetidae + Periscelididae are consistently grouped together. The position of the Teratomyzidae is uncertain. The genera Stenomicra, Cyamops and Planinasus consistently grouped with the Periscelididae. The sister-group of Aulacigaster is an undescribed genus from Malaysia, and I propose to expand the definition of the Aulacigastridae to include that taxon.
In chapter 3, I revise the World species of the genus Aulacigaster Macquart, now numbering 42. New species are described for the Neotropical (28 spp) and Oriental (1 sp) regions, and the genus is divided into six species groups, of which five are new. Keys to species, diagnoses, detailed distributional data, notes on the biology and illustrations are provided to assist species identification. Based on a quantitative phylogenetic analysis, I provide evidence for the monophyly of the Aulacigaster, and the included species groups
In chapter 4, I describe the internal female reproductive tract of six species of Opomyzidae, representing three of the four known genera of the family, which I compare with the female tract of other opomyzoid families. The following structures of the female genital tract may prove informative within the context of phylogenetic analyses of the Opomyzoidea: the presence/ absence of multiple chambers in the ventral receptacle; the degree of sclerotization and shape of the ventral receptacle; and the presence of a ring-shaped sclerotization on the wall of the vagina, posterior to the ventral receptacle.||en_US