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Inbreeding, genetic load and morphometric variation in natural populations of Dryers iulia (Lepidoptera, Nymphalidae)

Karen Luisa Haag^I; Aldo Mellender de Araújo^II

^IDepartamento de Genética, UFPR, Caixa Postal 19071, 81531-970 Curitiba, PR, Brasil
^IIDepartamento de Genética, UFRGS, Caixa Postal 15053, 91501-970 Porto Alegre, RS, Brasil. Send correspondence to A.M.A.

ABSTRACT

Because of their wing color pattern homogeneity throughout its range, Dryas iulia populations are thought to be large and uniform. In the present paper we attempted to verify this hypothesis, analysing six samples from distinct places in Southern Brazil (state of Rio Grande do Sul) by different approaches. We estimated the mean inbreeding coefficient (F) and the genetic load of populations, using a regression between the rates of non-eclosion of eggs and the inviability of individuals from progenies on f. We also made morphometric analyses, using the forewing length. These approaches revealed that populations show a high level of inbreeding (0.07 < F < 0.12), with a genetic load of three lethal equivalents per gamete when egg to adult survival is considered. The wing length means significantly differed among samples from some localities. Males also showed significantly longer forewings than females. Comparing these results with the hypothesis of uniformity of populations, we conclude that they are not as homogeneous as they formerly were thought to be.

Keywords: inbreeding; genetic load; morphometric; natural populations; Dryers iulia.

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