A Description of the Developmental Stages of Aploderus caelatus (Gravenhorst, 1802) (Coleoptera: Staphylinidae)

Abstract

The egg, three larval instars, prepupa and pupa of Aploderus caelatus (Grav.) are described for the first time. Also given is a completed description of its adult. The eggs occur in clusters, a micropyle absent. The particular larval instars differ between one another in size of the body, degree of sclerotisation of head and tergites, as well as in colour and microsculpture. There are also significant differences with regard to chaetotaxy. The number of setae on most sclerites of L1 is smaller than in L2 and L3. The chaetotaxy of the last two instars is identical. Among the known common coprophagous larvae of Oxytelinae the described larva is most similar to that of Oxytelus piceus (L.). The differences mainly pertain to the structure of the mouthparts, some cuticular forms and general view of the body. The pupa is a exarata type, with relatively sparse setae. It differs from the pupae of other coprophagous Oxytelinae known so far in: lack of setae on most body sclerites, length of antennae and general view. Its characteristic is the occurrence of a pair of setae close to the eyes divided into three branchs, and the structure of spiracles. Distinctly marked sexual dimorphism of the pupa, which is discernible in the structure of the terminal sternites of the abdomen, has been found. In the case of the adults sexual dimorphism is marked by the structure of the head, terminal sternites of the abdomen and body size (the width of the head and pronotum, the length of the body).