Diagnoses and re-description of Coccinellid beetles, Stethorus rani Kapur and Stethorus aptus Kapur (Coleoptera: Coccinellidae) preying on tea red spider mite Oligonychus coffeae Nietner (Acari: Tetranychidae)

Abstract

Stethorus aptus Kapur and Stethorus rani Kapur are two important predatory ladybird beetles preying on red spider mite, Oligonychus coffeae Nietner infesting tea in South India. This study re-describes these two predatory beetles since it was found that the original descriptions were scanty. In this study, an attempt has been made on the diagnoses with a detailed description which is supplemented with current terminology, illustrations, coloured images, morphometrics and SEM images of both species. The morphometrics done in the study deals with the length and width of the egg, larvae, pupa and adult of both male and female. Body colour, setae, clypeus, eyes, antennae, scutellum, elytron, abdomen, legs and genitalia were re-described. The present study of the surface morphology with SEM puts forward the differences observed in the size of the punctures on pronotum of two species and the proportion of elytral length versus width as additional diagnostic characters of significance.