Variation in the Female Frenulum in Tortricidae (Lepidoptera). Part 2. Olethreutinae

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This paper, treating the tortricid subfamily Olethreutinae, represents the second in a proposed three-part series examining variation in the number of bristles in the frenulum of female tortricid moths. Based on an examination of 6,333 individuals of 1,464 species representing 188 genera of Olethreutinae, the number of bristles in the female frenulum varies from one to six, and it is sometimes asymmetrical on the same specimen (7.5% of individuals examined). A three-bristled frenulum is the most common condition in Microcorsini, Endotheniini, Bactrini, Gatesclarkeanini, Olethreutini, Enarmoniini, and Eucosmini, with varying degrees of intraspecific variation in number within each tribe. However, in both Eucosmini and Enarmoniini several genera have a predominantly or exclusively two-bristled frenulum (e.g., Gypsonoma Meyrick, Herpystis Meyrick, and Rhopalovalva Kuznetsov in Eucosmini; Hystrichophora Walsingham, Neoanathamna Kawabe, and Pseudacroclita Oku in Enarmoniini). In Grapholitini, two- and three-bristled frenula occur in nearly equal frequency, suggesting that this character may be of some phylogenetic significance, but an overall pattern is not immediately obvious. In contrast to the situation in Chlidanotinae, where the distribution of the two- and three-bristled frenulum corroborates previously proposed phylogenetic hypotheses, we conclude that variation in the number of bristles in the frenulum in Olethreutinae is not phylogenetically informative at higher levels (e.g., tribes, subtribes) owing to the high degree of intrageneric and intraspecific variation. However, the number of bristles may be of phylogenetic significance at the generic level, particularly in Eucosmini and Grapholitini.