Redescription of Pallisentis (Brevitritospinus) Indica (Acanthocephala: Quadrigyridae) from Channa punctatus Bloch & Schneider (Channidae) in Aligarh, India with New Understandings of Old Structures.

Abstract

Pallisentis indica Mital and Lal, 1976 was originally described from Channa gachua Hamilton (Channidae) in Kali Nadi River, Aligarh, India. The parasite was later placed in the subgenus Brevitritospinus Amin, Heckmann, Ha, Luc, and Doanh, 2000 . Our collection from the spotted snakehead Channa punctatus Bloch & Schneider in another locality of the same stream in Aligarh produced many specimens with variable traits, revealing new structures that have never before been described in the Acanthocephala, especially relating to the ducted trunk spines. The proboscis has 4 circles of 10 hooks each, with hooks in the anterior 2 circles being considerably larger than those in the posterior 2 circles. Y-shaped trunk spines are ducted in 2 regions separated by a spineless zone. The anterior collar spines are in complete rings of 9-17 circles of crowded spines and the larger posterior trunk spines are in 1 (posterior) to 41 (anterior) circles extending to level of cement glands in males posteriorly. Considerable variations from the original description and new structures are reported for the first time.