Tephritid Olfaction: Morphology of the Antennae of Four Tropical Species of Economic Importance (Diptera: Tephritidae)1

Abstract

Four types of sensilla are present on the antennal surface of four tropical tephritid species of economic importanc—the Mexican fruit fly, Anastrepha ludens (Loew); the Mediterranean fruit fly, Ceratitis capitata (Wiedemann); the melon fly, Dacus cucurbitae Coquillett; and the oriental fruit fly, D. dorsalis Hendel. Three types of porous sensilla occur only on the funiculus. Two types of multiporous pitted sensilla (MPS)—thick-walled and thin-walled—house dendritic branches, and both are probably chemoreceptors. Electrophysiological recordings from cells associated with a thick-walled MPS in C. capitata showed that it responds to trimedlure, a known attractant. Multiporous grooved sensilla also occurring on the funiculus were, however, too small for recordings. No-pore sensilla are found only on the scape and pedicel, and electrophysiological recordings show them to be mechanoreceptors.