Meeting Abstract

P2.116  Saturday, Jan. 5  Cricket antennae shorten when bending (Acheta domesticus (L.)) BUSTAMANTE, JR., J.*; LOUDON, C.; Univ. of California, Irvine; Univ. of California, Irvine cloudon@uci.edu

Insect antennae are important mechanosensory and chemosensory organs. Insect appendages, such as antennae, are encased in a cuticular exoskeleton and are thought to bend only between segments or subsegments where the cuticle is thinner and more flexible (intersegmental membrane). Antennae will bend or deflect in response to forces, and the resulting bending behavior will affect the sensory input of the antennae. In some cricket antennae, such as in Acheta domesticus, there are a large number (>100) of subsegments of variable length, and yet these antennae bend in a continuous smooth curve without kinks. We evaluated whether these antennae bend only at the joints between subsegments, which has always been assumed but not tested. In addition we questioned whether an antenna undergoes a length change as it bends, which could result from some patterns of joint deformation. Using constrained live crickets and a high-magnification dissecting microscope, we took photos of antennal flagella when straight and when bent, and digitized the images to analyze the morphological reconfiguration. Measurements were conducted with both male and female adult crickets (Acheta domesticus) with bending in four different directions: dorsal, ventral, medial, and lateral. Bending did occur only at the joints between subsegments, and antennae shortened during bending, regardless of gender or bending direction. Antennal shortening during bending would prevent stretching of antennal nerves and may promote hemolymph exchange between the antenna and head.