Immature stages of Euchirinae (Coleoptera:Scarabaeoidea): genera Cheirotonus and Propomacrus with comments on their phylogeny based on larval and adult characters
We report the discovery of the larvae of Propomacrus bimucronatus (Pallas, 1781) in their natural habitat; providing notes on their biology based on field observations and laboratory-bred specimens. We give a detailed description of Cheirotonus formosanus Ohaus, 1913 and P. cypriacus Alexis & Markis, 2002 larvae as well as a redescription of the immature stages of P. bimucronatus and present the first diagnosis of larval Euchirinae. Based on 105 morphological and ecological characters of adults and larvae in 24 taxa of Scarabaeoidea, we discuss the phylogenetic relationships of Euchirinae within the group. Our results corroborate Euchirinae monophyly, supported by two larval synapomorphic characters; however, no adult autapomorphic characters were detected. The results of 15 separate phylogenetic analyses (differing in the set of terminalia, characters and in the optimality criteria) indicate a possible sister group relationship between Euchirinae and a clade comprising Melolonthinae + Rutelinae + Dynastinae, with Cetoniinae being a sister group to the whole clade. Larval characters represent a valuable source of information for the systematics of Scarabaeoidea; however, special effort should be paid to improve the still unsatisfactory sampling of immature data.