FOREGUT MICROSPINES IN 4 FAMILIES OF COCKROACHES (BLATTARIA)

The microspines of the cockroach foregut were investigated in order to determine their fine structure, variation, patterns of distribution, and possible functions. The following were studied: Blaberidae (4 spec ies), Blatellidae (3 species), Blattidae (2 species), and Cryptocercid ae (one species). Elongate microspines (over 30 mum), usually several attached to a basal plate. were found in the buccal cavity and anterio r and posterior pharynx of blaberids and blattids, whereas moderate (1 5-20 mum) to short (1-5 mum) miscrospines were found in 2 regions in t he blattellid and cryptocercid cockroaches. Short microspines (1-5 mum ) individually attached to a basal plate occurred in the esophagus, cr op, proventriculus and stomodeal valve regions in all families studied . Microspines appear to be useful in understanding systematics and evo lution of cockroaches. The possible role of elongate microspines in re taining food particles during regurgitation behavior is postulated.