Morphological and physiological characteristics of the antennular short hair sensilla of the blue crab,Callinectes sapidus

Abstract

The four short hair sensilla (SHS) on the proximal antennular segments of Callinectes sapidus consist of a tapered shaft covered on all but the inner surface with unbranched hairs. Waterborne mechanical stimuli do not excite the SHS, whereas antennular movement evokes high amplitude activity in afferent fibers. Phasic sensory elements from the anteriormost sensillum respond primarily to anteroventral deflection, while the other three sensilla contain sensory elements which respond to posteroventral deflection. The similarity of SHS to the Type I long hair sensilla of the cockroach trochanteral plate suggest they perform a comparable movement‐limiting function. The SHS may also interact with afferent activity from the statocysts.