description of pallisentis (brevitritospinus) punctati n. sp. (acantho¬cephala: quadrigyridae) from channa punctatus in ba¬reilly, uttar pradesh, india

background: the genus pallisentis is an endoparasitic acanthocephalan inhabit­ing the intestinal walls. hooks and spines of the worm are significant taxonomical and adaptive tools. methods: the parasites were fixed, dehydrated and examined under olym­pus bx 53 microscope with dic attachment, digital camera and cellsens imag­ing system [light microscopy (lm)] and fixed in 2% glutaraldehyde in 0.1 m cacodylate buffer, dehydrated, rotary-coated with gold palladium in neocoater 100-240v and examined in neo jcm-6000 [scanning electron microscopy (sem)]. results: p. punctati n. sp. (prevalence 65.51%; mean intensity 3-6 par/host) is de­scribed. females almost twice as large as males; proboscis hooks small; collar spine rows similar [16] and constant in both sexes but number of spines per row greater in females [22] than males [14]; trunk spine rows 28-39 (spines per row 14-18) in females and 20-26 (spines per row 10-12) in males. spine length of females almost twice as long as males, spines extend up to posterior testis in males and ¾ of total body length in females, saefftigen’s pouch present, nuclei in cement gland 10-11, seminal vesicle, bursa and egg size small. sem indicated lack of micro sculptures, and spines embedded on pre-trunk and trunk. sex-based differences apparent (hook sizes, greater number of spines per row and longer spines in pre-trunk and trunk of females). male trunk spine was narrower and of lateral spine with characteristic hooked appearance. conclusion: a new species of pallisentis based on lm and sem is described, sexual diversity in hook and spine structure is reported.