Sexual dimorphism in morphology and development of the pest chigger, Eutrombicula cinnabaris (Acari: Trombiculidae)

Abstract

Sexual differences in duration of postlarval life stages and morphology of larval, deutonymphal, and adult stages were examined in the pest chigger, Eutrombicula cinnabaris (Ewing). Multivariate analyses were used to test for differences between the sexes and to identify characters that could separate the sexes. Statistically significant differences were found between sexes in the postlarval life history and morphology of adults. Sexual differences were not found in the morphology of larval or deutonymphal stages. Accurate identification of gender was accomplished independently by use of 2 life history characters and by 9 adult morphological characters.

Key words :

• Acari
• Trombiculidae
• chigger mites
• sexual dimorphism