Genus Affecauda Hall & Chambers, 1999

Emended Diagnosis: Body elongate, noticeably narrow posterior to gonads; pronounced curve dorsoventrally. Tegumental annulations present. Ventral sucker round, at posterior extremity of body, protuberant. Pharynx elongate, subterminal. Oesophagus long, sigmoid, sometimes with single loop, invested with glands along entire length; lining distinctive, thick. Oesophageal bulb ovoid, distinct. Intestinal bifurcation immediately posterior to oesophageal bulb; caeca terminate just posterior to level of genital aperture. Testes 2, entire, ovoid, tandem, in middle or posterior third of body. Seminal vesicle external, bipartite. Pars prostatica large, cylindrical, tapering posteriorly, surrounded by profuse prostatic gland cells which partially penetrate cirrus­sac. Cirrus­sac spherical, ventral to caeca. Ejaculatory duct short, simple, expanding distally. Genital atrium large, convoluted. Genital pore median, ventral to caeca. Ovary ovoid, inter­ or pretesticular. Vitellarium follicular; follicles largely restricted to anterior half of body, extend from posterior margin of pharynx to immediately anterior to anterior testis; dorsal, ventral and lateral fields confluent. Uterus entirely pre­ovarian. Opening of uterus unspecialised; metraterm absent. Excretory papilla prominent. Excretory vesicle globular. Primary collecting ducts arise laterally. Intestinal parasites of herbivorous marine fishes ( Acanthuridae and Siganidae only) in the Indo­West Pacific. Type­species Affecauda annulata Hall & Chambers, 1999 .