On an Aberrant Structure of the Aedeagus in Harpalus latus (L.) (Coleoptera, Carabidae)

Abstract

The aberrant structure of the aedeagus of a male of Harpalus latus (Linnaeus, 1758), found in northern Germany (Salzhaff, Mecklenburg-Western Pomerania), is described. The aberrant aedeagus looks as normal but differs markedly from that of other specimens in having the median lobe relatively shorter as compared with the body length, the basal bulb relatively larger, the apical orifice smaller, situated dorsally, the terminal lamella much longer, the internal sac lacking any sclerotized elements, the right paramere large, similar to the left one. It is hypothesized that the development of the aedeagus was stopped for some reason, for example, as a result of hormonal imbalance, at an early ontogenetic stage. The aberrant aedeagus is more plesiomorphic than the aedeagus of normal specimens in having a dorsal position of the apical orifice, in similar left and right parameres, and in the absence of any sclerotized elements in the internal sac.