Classification of the weevil tribe Lignyodini (Coleoptera, Curculionidae, Tychiinae), with revision of the genus Plocetes.By Clark, W.E.
Clark, W.E. 1982. Classification of the weevil tribe Lignyodini (Coleoptera, Curculionidae, Tychiinae), with revision of the genus Plocetes
. Transactions of the American Entomological Society 108(1/2): 11-151.
The 89 recognized species of Lignyodini are assigned to two genera, Lignyodes Dejean, with subgenera Lignyodes (13 species, Nearctic and Palearctic), Chionanthobius Pierce (3 species, Nearctic and Neotropical), and Neotylopterus (7 Nearctic species, 1 Neotropical species not seen), and Plocetes (65 species, 1 Nearctic, all others Neotropical). Diagnoses and discussions of relationships of the tribe Lignyodini and of the genus Lignyodes and its subgenera, and of the genus Plocetes, are presented, along with keys to the genera of Lignyodini and subgenera of Lignyodes. The species of Plocetes are diagnosed, described or redescribed, illustrated, and keyed, their known geographic distributions stated. All but one of the species of Plocetes, P. ulmi LeConte, are newly transferred to that genus from Lignyodes (or its synonym Thysanocnemis), newly named and described (42 species), or fall to Plocetes because their former genera, Hamaba Casey and Rosella Whitehead, are placed in NEW SYNONYMY under Plocetes. The species of Lignyodes are hypothesized to form a monophyletic group because of synapomorphies, including association with plants in the family Oleaceae (genera Chionanthus, Forestiera, Fraxinus, Ligustrum, Osmanthus, and Syringa). Similarly, the species of Plocetes have synapomorphies, including association with plants in the family Rubiaceae (genera Alceis, Cephalanthus, Macrocnemum, Rondeletia, and Sickingia). Lectotypes are designated for P. zonatus (Champion), P. minor (Champion), P. rufescens (Champion), P. seminiger (Hustache), P. singularipes (Hustache), P. obscurus (Champion), P. ornatus (Champion), P. suturalis (Champion), P. longirostris (Kirsch), P. subfasciatus (Kirsch), P. versicolor (Champion), and P. ulmi LeConte. The name P. laevirostris (Champion) is placed in NEW SYNONYMY under P. brevis (Champion).