Barcoding pest species in a biodiversity hot-spot: the South African polyphagous broad-nosed weevils (Coleoptera, Curculionidae, Entiminae).

Steffan Hansen,Laure Benoit,Julien M Haran,Pia Addison

doi:10.3897/bdj.9.e66452

Abstract

Polyphagous broad nosed weevils (Curculionidae: Entiminae) constitute a large and taxonomically challenging subfamily that contains economically significant agricultural pests worldwide. South Africa is a hot-spot for biodiversity and several species of indigenous and endemic genera of Entiminae have shifted on to cultivated plants, with some being phytosanitary pests. The sporadic pest status of many species (where the species has an occasional economic impact on the agricultural industry, but is not encountered often enough that is is readily recognisable by researchers and agricultural extension workers) and the presence of pest complexes and cryptic species represent an identification challenge to non-specialists. Furthermore, no comprehensive identification tools exist to identify immature stages that may be found in crops/soil. In this paper, a curated barcoding database with 70 COI sequences from 41 species (39 Entiminae, 2 Cyclominae) is initiated, to assist with the complexity of identification of species in this group.

Highlights

Curculionidae Latreille, 1802 is a hyperdiverse family of beetles (Coleoptera), containing approximately 17 subfamilies and more than 51000 described species (Oberprieler et al 2007, Bouchard et al 2011, Leschen and Beutel 2014)
South African crops may contain complex assemblages of species of PBNW for which species identification is challenging for non-specialists and an issue compounded by the presence of cryptic species in some taxa (Haran et al 2020)
This study reveals some challenges with the application of this approach to PBNW in South Africa

Summary

Introduction

Curculionidae Latreille, 1802 is a hyperdiverse family of beetles (Coleoptera), containing approximately 17 subfamilies and more than 51000 described species (Oberprieler et al 2007, Bouchard et al 2011, Leschen and Beutel 2014). The adults have deciduous mandibular cusps that are used to dig their way out of soil after pupation and are actively lost while feeding, leaving a distinctive scar (Thompson 1992, Marvaldi 1997, Marvaldi and Lanteri 2005) These deciduous cusps or the related scars in adult entimines are a commonly-used synapomorphy that establishes the monophyly of the subfamily; it should be noted that it is not an autapomorphic feature, as it is shared by other subfamilies, possibly having evolved several times in Curculionidae or being secondarily lost by some taxa classified within Entiminae (Marvaldi 1997, Thompson 1992). The first two larval features are considered the most important synapomorphies for the monophyly of the Entiminae and are autapomorphies for the subfamily (Marvaldi 1998, Oberprieler et al 2007, Marvaldi et al 2018)

Methods

Results

Discussion

Conclusion