PATEK, S.N.*; GOLDMAN, J.A.; University of California, Berkeley; American Institute of Biological Sciences: More than one way to sniff: a comparative analysis of palinurid lobster antennules

Lobsters �sniff� by flicking their antennular flagella. They discretely sample odors in the environment by rapidly closing the flagella, which permits water to flow through sensory hairs, and then slowly opening the flagella, which causes water to remain trapped in the sensory hairs. Panulirus argus is the model system in palinurid lobsters for studying chemoreception, but few studies have examined olfaction in other palinurid species. We conducted a comparative study of antennule morphology across 12 lobster genera in three families, including 13 species in the palinurid family. Using high speed video, kinematic analyses and morphometrics, we then compared antennule flicking in Palinurus elephas to published values for Panulirus argus. We found that Palinurus elephas flicks at rates an order of magnitude higher with flagella that are almost seven times shorter than those of Panulirus argus. When antennules were compared across lobsters, we found that Palinurus elephas is more typical of palinurid and other lobster families, whereas Panulirus species sample far larger areas of water per flick than any other lobster genus. Hence, while Panulirus argus is a highly informative model system in which to study chemoreception, the distinct anatomy and kinematics of their antennules suggests a unique strategy for detecting low odor concentrations in the environment.