The Life Cycle of Ctenothrips distinctus (UZEL, 1895) (Insecta: Thysanoptera) and its Influence on the Host Plant Convallaria majalis L.

Abstract

In this paper, we describe the morphological characteristics of the preimaginal stages of Ctenothrips distinctus, as well as its life cycle in temperate climate conditions. We also revise the key characters of the second larval instar of C. distinctus, which were previously confused with those of Taeniothrips picipes (Zetterstedt, 1828). The morphological characteristics of the C. distinctus propupa and pupa represent their adaptations to moulting in the soil, not on the host plant. The study of the biology of C. distinctus is supplemented by an analysis of the impact of the foraging by this insect on its host plant Convallaria majalis. Based on the morphological, anatomical and histological analyses of Lily of the Valley leaves, we show that both adults and larval instars feed on the epidermal cells of both the upper and lower sides of the leaf blade in C. majalis. However, the assimilation parenchyma cells located immediately below the epidermis at the feeding site retain their shape.