Unveiling soil ciliate diversity: Taxonomy of two novel hypotrich ciliates (Alveolata: Ciliophora) from agricultural soil in Mathura, India

The present study investigates the morphology of two novel hypotrich ciliates, Pseudourosomoida kadamberiae gen. et sp. nov. and Neoholosticha vikali gen. et sp. nov., using live observation and protargol staining. These species were isolated from a soil sample collected from a pumpkin field in Mathura, India. Pseudourosomoida kadamberiae has an ellipsoid body (~58 × 21 μm in protargol preparations), two macronuclear nodules, no micronucleus, colorless to yellowish cortical granules, four dorsal kineties, an adoral zone composed of 17–30 membranelles, and no caudal cirri. Its morphogenesis begins with the development of an oral primordium near the leftmost transverse cirrus, similar to that in species of the genus Urosomoida Hemberger in Foissner, 1982. Neoholosticha vikali has a body size of ~115 × 31 μm in protargol preparations, yellowish-green cortical granules, ~85 ellipsoidal macronuclear nodules, one or two micronuclei, three frontal cirri, one buccal cirrus, two transverse cirri, about 45 cirri in the left and 48 in the right marginal rows, an adoral zone with ~32 membranelles, 6–8 dorsal kineties, and 7–12 caudal cirri. The study provides a detailed taxonomic account of both species, contributing to the understanding of soil ciliate diversity from India.