December 2007 - The Indian Society for Parasitology

C. leucas, a new species115rare species, Cathetocephalus leucas sp. nov isdescribed from the spiral valves of Carcharhinusleucas. The identification of the genus was done byfollowing the standard books like Yamaguti (1959),Schmidt (1986), Khalil et al., (1994) and recentliterature pertaining to the genus (Dailey andOverstreet, 1973; Schmidt and Beveridge, 1990;Pramanik and Manna, 2006)MATERIAL AND METHODSconventional techniques. Figures were drawn with theaid of camera lucida. Measurements are given inmillimeters, unless otherwise stated. A new and a rarecestode, Cathetocephalus leucas sp. nov wasencountered during the study from the spiral valve ofthe intestine.RESULTSClass: CestodaAbout 125 Carcharhinus leucas (Valenciennes, 1839)Sub-class: Eucestoda Southwell, 1925were examined thoroughly for the cestode parasites ina survey to study cestode parasitic fauna from theOrder: Tetraphyllidea Carus, 1863sharks at Visakhapatnam coast, Bay of Bengal. Spiral Family: Cathetocephalidae Dailey and Overstreet,valves of the intestine offer an excellent habitat to 1973cestode parasites. Spiral valves were separated intophysiological saline to remove excess mucus and wereGenus: Cathetocephalus Dailey and Overstreet, 1973cut open with a longitudinal incision. Parasites were Cathetocephalus leucas n. sp.carefully isolated from the spiral valves and collectedin petridishes filled with saline solution. Due care was Only four specimens were obtained from the spiraltaken to prevent the scolex as well as strobila of valve of a single bull shark, Carcharhinus leucasparasites from being damaged as scolex being the key (Valenciennes, 1839) and were found to be deeplyfeature for the identification of a cestode. Parasites embedded into the intestinal wall.were flattened between two slides or under theDESCRIPTION (Based on measurement of fourpressure of slide and a coverslip, post fixed in A.F.Aparasites, Plate-I, Figs.1-2): Parasites long, thin,(alcohol, 85 ml; formalin, 10 ml and acetic acid, 5 ml)creamy white and measure 7–8 cm in length. Wormsand stained with alum carmine. Permanent wholeslightly acraspedote and apolytic in nature. Scolexmount preparations were made by employing theCathetocephalus leucas n.spFig. 1. ScolexFig. 2. Mature Proglottid