USE OF CEMENT FOR ATTACHMENT IN NEOCALCEOSTOMOIDES-BRISBANENSIS, A CALCEOSTOMATINE MONOGENEAN FROM THE GILL CHAMBER OF THE BLUE CATFISH, ARIUS-GRAEFFEI

The thin, weakly muscular, disc-shaped haptor of the calceostomatine m onogenean Neocalceostomoides brisbanensis is attached to surfaces in t he gill chamber of its catfish host by cement, It is unlikely that any suction is generated (there are no muscular loculi) and the hooks are reduced in size, Two distinctive secretions are associated with the h aptor: a finely granular secretion from glandular tissue within the ha ptor and anterior to it, which enters the dorsal haptor tegument near the periphery of the disc and spreads throughout the ventral haptor te gument; a coarser secretion produced in the peduncle and posterior reg ion of the body, which finds its way to gland openings near the hamuli via centrally situated large and small haptor reservoirs, It seems mo st likely that the tegumentary secretion is the cement, but other poss ibilities are discussed, It is suggested that the increasing importanc e of cement for haptor attachment in calceostomatines has led to the d evelopment of a weakly muscular, foliaceous haptor and a progressive r eduction of the hooks.