Antennal sensilla of Cyclocephala barrerai (Coleoptera: Melolonthidae): morphology, sexual dimorphism, allometric relationships, and function.

This article focuses on the morphology, sexual dimorphism, and electrophysiological function of antennal sensilla in Cyclocephala barrerai Martínez, a scarab beetle species distributed in Mexico. The study identifies and classifies various sensilla types on the antennae, notably finding that males have larger antennal lamellae with more and larger placodea IV sensilla, which detect plant volatiles, cuticular hydrocarbons, and warm air, suggesting a role in mate and host plant location. Females exhibit a greater diversity of sensilla types but fewer total sensilla, possibly reflecting different ecological and reproductive roles. The research demonstrates positive static allometry in male placodea IV sensilla, indicating sexual selection influences the development of antennal structures to enhance reproductive success in this species.