Descriptions of the third instars of pristerophora picipennis (Solier) and schizochelus modestus Philippi (Coleoptera: Scarabaeidae: Melolonthinae: Macrodactylini) from Southern Chile

摘要

The third instars of Pristerophora picipennis (Solier) and Schizochelus modestus Philippi (Scarabaeidae: Melolonthinae: Macrodactylini) are described and illustrated. The descriptions are based on larvae reared from eggs laid by adults in the laboratory and on larvae collected in the field. These are the first descriptions of larvae of Macrodactylini that live and feed in the root zone of pastures in southern Chile. The larvae of the two species can be distinguished easily by the presence (S. modestus) or absence (P. picipennis) of palidia. Also, setae on the dorsum and the dorsal anal lobe are sickle-shaped in S. modestus and short, slender, straight, and acute in P. picipennis.