Idiosomal setae analysis in Oligonychus peruvianus and Oligonychus perseae (Acari: Tetranychidae) from different hosts

Abstract

The phytophagous mites, Oligonychus peruvianus (McGregor, 1917) and Oligonychus perseae Tuttle, Baker and Abbatiello, 1976 are considered occasional pests in several tropical crops. Due to morphological similarities between them, both species are difficult to differentiate. In this study, morphometrical and chaetotaxic analysis were made to discriminate O. peruvianus from O. perseae. Idiosomal length and width and idiosomal chaetotaxy were measured in O. peruvianus females collected on Manihot esculenta Crantz or Persea americana L. trees from Venezuela and then compared to O. perseae specimens from avocado trees from Costa Rica. Principal Component Analysis (PCA) of the idiosomal chaetotaxy showed existence of three distinct groups, the first group represented by O. peruvianus individuals collected in avocado trees; the second by O. perseae from avocado and the third by O. peruvianus from cassava plants. Our results confirmed taxonomic value of chaetotaxy as a tool to discriminate these mentioned Tetranychidae species.