Morphological description of the white grub Melolontha incana (Coleoptera: Scarabaeidae: Melolonthinae: Melolonthini)

Microsc Res Tech. 2021 May;84(5):921-928. doi: 10.1002/jemt.23653. Epub 2020 Nov 24.

Abstract

Melolonthinae are the largest subfamily of Scarabaeidae, considered as serious pests for their larvae attacking plant roots and tubers. The edaphic larvae are difficult to be identified because the study on larval taxonomy is far from satisfactory. In this study, multivoltine white grubs Melolontha incana (Motschulsky, 1853) were investigated using light and scanning electron microscopy, in order to provide more morphological characters for the pest identification. The white grubs are atypical for the epipharynx bearing 14 heli arranged in two rows; the mandible is furnished with a patch of minute granules; the maxilla is equipped with 18 acute stridulatory teeth arranged in line; each femur and tibiotarsus is furnished ventrally with a cluster of fossorial setae. The morphological comparisons with the other melolonthine species were provided. The adaptative relationship between the morphological feature and the multivoltine life history were briefly discussed.

Keywords: SEM; mandible; morphological adaptation; raster; stridulatory organ.

MeSH terms

  • Animals
  • Coleoptera*
  • Larva