Description of Pallisentis thapari n. sp. and a re-description of Acanthosentis seenghalae (Acanthocephala, Quadrigyridae, Pallisentinae) using morphological and molecular data, with analysis on the validity of the sub-genera of Pallisentis.

One new species of Pallisentis Van Cleave, 1928 is described from Channa punctatus (Bloch) from Gomti River (tributary of the Ganga River), in Uttar Pradesh, Lucknow district, India. Pallisentis thapari n. sp. is characterized morphologically by individuals having a globular proboscis armed with rooted hooks in 4 circles of 8-10 hooks each, the first circle more than 100 long and hooks gradually declining in size posteriorly. The trunk is cylindrical, with collar spines comprised of 15-17 complete circles of spines, each ring with 12-22 spines. As common in members of the genus, a narrow spine-free zone lies in between the rings of collar and trunk spines. Field of spines extends posteriorly to half of the body length, ending above the level of testes in males and slightly past mid-body in females; trunk spines have an optically-dense Y-shaped core. The trunk is only slightly wider at the anterior end. The syncytial cement gland of males contained 23-30 nuclei. Individuals of Channa striatus Bloch from the same locality also were infected with the new species. A second species of Acanthocephala, Acanthosentis seenghalae Chowhan, Gupta, Khera, 1988, was found as a parasite of Puntius sophore (Hamilton) from the same locality. The proboscis is short, globular, with 3 circles of hooks each circle bearing 6 hooks. The trunk is broad in the middle and tapered at both ends, with the posterior end narrower than the anterior end. Twelve to 16 circles of spines, each with 21-40 spines, extend from anterior end to just past mid-body in males and only to mid-body in females. The syncytial cement gland of males contains 6-10 nuclei. The analysis of 18s rDNA identified two clades of a monophyletic Pallisentis and placed the isolate of P. thapari n. sp. within that clade; previously established subgenera were not supported by the results of the analysis.

Four New Species of the Genus Pallisentis (Quadrigyridae, Van Cleave, 1920) from Freshwater Fish in Uttar Pradesh, India.

AIMS: Four new species of genus Pallisentis (Van Cleave, in Records Indian Mus 30:147-149, 1928) are described from the state of Uttar Pradesh, India, infecting freshwater fish. METHODS: The detailed morphology of all four species was studied using light and scanning electron microscopy. RESULTS: They are: Pallisentis lucknowensis n. sp. from Channa punctatus (Bloch 1785); Pallisentis amini n. sp. from Channa striatus (Bloch 1785); Pallisentis meyeri n. sp. from Channa punctatus (Bloch 1785); and Pallisentis unnaoensis n. sp. from Glossogobius giuris (Hamilton 1822). CONCLUSION: All four Pallisentis spp. differed from other congeners because of the morphology of the proboscis hooks, size and shape of proboscis hooks, shapes, number and arrangement of trunk spine, size of cement gland, numbers of cement gland nuclei, lemnisci, size and position of testes, gonopore, etc. An updated key of genus Pallisentis of 33 species accepted as valid are provided. The present study extends the number of Pallisentis from 29 to 33 species.

On a new species of Neoechinorhynchus Hamann, 1892 (Neoechinorhynchinae Travassos, 1926) from Eleutheronema tetradactylum (Shaw, 1804) from Digha coast, West Bengal, India.

Neoechinorhynchus (Neoechinorhynchus) dighaensis n. sp. is described from the intestine of the fourfinger threadfin fish Eleutheronema tetradactylum (Shaw, 1804) from the Digha coast, West Bengal, India. Females were larger than males. In the male dorso-ventral lacunar canals well developed. Middle hooks in perfect circle, smaller than anterior hooks. Posterior hooks slightly smaller than middle hooks. Lateral anterior proboscis hooks larger than the others in same circles. Lateral posterior proboscis hooks equal to others in same circles. Lemnisci equal, longer reaching to testes in male. Male reproductive system usually occupies half of the total body length. Eggs were elliptical in shape with concentric membrane. Cement gland long, containing seven giant nuclei.