Systematic and ecological studies of the <i>Apodemia mormo</i> complex (Lepidoptera: Riodinidae) in southern Arizona and southern New Mexico

TitleSystematic and ecological studies of the Apodemia mormo complex (Lepidoptera: Riodinidae) in southern Arizona and southern New Mexico
Publication TypeThesis
Year of Publication1981
AuthorsForbes GS
Number of Pages83
Date Published1981
UniversityNew Mexico State University
CityLas Cruces, New Mexico
Thesis TypeM.S. Thesispp
Call Number00068
KeywordsApodemia,ecology of, Apodemia,phenotypic variation, butterfly,SEE <LEPIDOPTERA>, dissertation, dissertations, invertebrate, Apodemia,systematics, Lepidoptera,Apodemia, theses, thesis
AbstractPopulation samples of the polytypic riodinid butterfly Apodemia mormo from the southwestern United States and northern Mexico were studied to determine the distribution of phenotypic variation. In all, 1,813 specimens from 103 locales were examined; 464 specimens were used in cluster and discriminant analysis procedures. The study revealed a highly diverse assemblage consisting of latitudinal and attitudinal clines, polytopic races, complex intergrade zones, and extensive individual variation. Variation present in the study area (southern Arizona to western Texas) was compared with variation patterns on California, Colorado, and Baja California populations. Intergrade zones are interpreted as possibly the result of local intermediacy in selective factors rather than physical contact of adjoining races. Gene flow appears to be greatly restricted among neighboring populations in the region of intergradation. Variation in A. mormo may be determined by such factors as thermoregulation, cryptic coloration, and foodplant associations. The role of historical selective factors is also acknowledged, as is the possibly nonadaptative nature of the color patterns due to pleiotropy. The polytopic nature of the insect, in which distant populations produce the some phenotypes, is evidence against the complex consisting of more than one species throughout most of the range. In a few cases, it is possible that local temporally or ecologically isolated populations (such as those seperated by foodplant preference) may be reproductively isolated species or sibling species.