The morphology of Laparocerus undatus Wollaston, 1864 and considerations on the tribe Laparocerini Lacordaire, 1863 (Coleoptera, Curculionidae, Entiminae)

Publication Type:Journal Article
Authors:A. Machado
Date Published:julio-diciembre
:Cyrtozemia, Laparocerini, Laparocerus, Laparocerus undatus, Merimnetes, Neomerimnetes

This morphological study of Laparocerus undatus Wollaston, 1864 covers the external and internal anatomy of the imago, including the alimentary canal, the central nervous system and the reproductive system. The anatomy of the larva and pupa, unknown in this genus, is also described. Laparocerus are Entimin weevils that bear some primitive characters, not frequent in the group. The justification of a tribe Laparocerini, not revised since it was established by Lacordaire in 1863, is considered. Similarities of adult and preimaginal characters with those of other genera and tribes are discussed, and genetic relationships are researched using partial sequences of the 16SrRNA gen obtained from GenBank for some twenty tribe represen- tative species. Laparocerus has important singular characters or a combination of them and is clearly separate from the other Entiminae studied. It has possibly a basal phylogenetic position within the group. Some combined diagnostic characters for Laparocerini are proposed, in particular: presence of a dehiscent mandible process (or its scar), phanerognatus mouth parts, long scape, eyes and antennal scroba not dorsal, suture of ventrites 1-2 arcuate at middle, ventrite 2 as long as 3 and 4 together, femora unarmed, tibiae mucronate with open corbels, claws connate, and VIII sternite of male membranaceous bearing a short spiculum relictum; in the larvae, antennae are cushion shaped with an oval base and the mala has five ventral setae; the pupa lacks mandibular setae. These and other characters are used to evaluate the other genera traditionally assigned to Laparocerini. Recent exclusion of some of these genera by other authors is corroborated and the removal of Merimnetes, Neomerimnetes and Cyrtozemia is here proposed. Asmaratrox and Straticus from Africa remain as Laparocerini, pending confirmation. Finally, the convenience of splitting Laparocerus into several genera or keeping it as a single genus with many subgenera is discussed in a biogeographical context.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith