Descriptions of the developmental stages and notes on biology of Timarcha rugulosa lomnickii Mill. [Coleoptera: Chrysomelidae]

Egg, larval instars I—III, prepupa and pupa of Timarcha rugulosa lomnickii Miller, 1867 are described and illustrated for the first time. Some details of the adult stages are also given. The life history of the species is presented. The larval instars differ from one another in terms of body size, body mass and in the intensity of colour of some structures as well as in the morphological structure of antennae, mouthparts (labrum, mandible) and microstructure of the head capsule surface. A characteristic feature of larval instar I is the presence of egg bursters. Pupal size and urogomphi are important sex-differentiating features. The adult stage shows variation mainly in respect of body size, the colour of cuticula reflection, the intensity and depth of microstructure on the head and pronotum surface. T. rugulosa lomnickii under the climatic conditions of Poland is a monovoltine species. The wintering stages are adult and egg. Oviposition occurs twice a year - in spring and autumn. Spring eggs develop without diapause, while autumn ones undergo diapause and larvae do not hatch before the spring of the following year.