First report of Melanterius inconspicuus (Coleoptera: Curculionidae: Cleogonini) from KwaZulu-Natal, South Africa, with observations of its development in black wattle

Abstract

Melanterius is a large genus of small weevils that primarily feed on the seeds of Acacia species occurring in their native range in Australia. In the latter part of the 20th century, five seed-feeding Melanterius species were released against several weedy Acacia species in South Africa as biological control agents. In early 2024, Melanterius weevils were detected damaging the vegetative plant tissues of trees in a commercial black wattle (Acacia mearnsii) compartment in the KwaZulu-Natal, South Africa. Morphological identification and DNA sequencing revealed that the weevils represent the species Melanterius inconspicuus, which is not one of the five species introduced in South Africa. This finding represents the first record of this Melanterius species outside of its native range in Australia and infesting black wattle, as well as the first record of a Melanterius species infesting vegetative tissues.