Comparative egg morphology of six species of the Albimanus section of Anopheles (Nyssorhynchus) (Diptera:Culicidae).

Scanning electron micrographs were used to describe and compare structures of eggs obtained from wild-caught females of 6 species of the Albimanus section of Anopheles (Nyssorhynchus) from South America, which includes important regional vectors of human malaria. Among species from the Oswaldoi Complex, eggs of Anopheles oswaldoi (Peryassu) were not differentiated from those of its sibling Anopheles konderi Galvao & Damasceno, and eggs of the former species from Brazil, Ecuador, and Suriname showed no regionally distinguishing characteristics. Eggs of Anopheles dunhami Causey were recognized by the reticulate beadwork of outer chorion on the dorsal plastron, 1 of several egg characters separating this species from the related Anopheles trinkae Faran and Anopheles nuneztovari Gabaldon. In both species examined from the Strodei Complex, Anopheles strodei Root and Anopheles benarrochi Gabaldon, Cova Garcia & Lopez, the anterior frill forms a distinctive ventral crown separated from the floats. Anopheles triannulatus (Neiva & Pinto), collected from 4 geographicsites, differed in the occurrence of perforated mounds on the dorsal plastron, but these chorionic structures and the extent of overlap of floats varied among eggs from single females. Changes among related species in the structure of the anterior frill and dorsal plastron are described for phylogenetic and developmental inferences.