Paracineta livadiana (Mereschkowsky, 1881)

Chatterjee, Tapas, Sautya, Sabyasachi, Dovgal, Igor & Gaikwad, Santosh, 2022, Report of suctorian ciliates (Ciliophora, Suctorea) as epibionts on meiobenthic nematodes in an oxygen minimum zone of the Arabian Sea, Indian Ocean, Zootaxa 5138 (4), pp. 492-500 : 494

Paracineta livadiana (Mereschkowsky, 1881)

( Fig. 2A, B )

Material examined: One individual found as epibiont on nematode host belonging to the genus Desmodora , from 202 m depth of Arabian Sea, Indian Ocean

Brief Description: Marine suctorian ciliate with a rounded body, almost covered with a stylotheca. The tentacles are arranged at apical body surface. Stylotheca with stem-like pseudostyle that does not widen until it transitions into the widened part of the stylotheca. The macronucleus is ellipsoidal, central.

Measurements from present specimen (in µm, based on one individual): Stylotheca length 32; lorica width 20; body length 21; body width 13; pseudostyle length 7; pseudostyle diameter 3; macronucleus length 5; macronucleus width 4; length of the tentacles 4–8.

Remarks: This is a marine or brackish-water species, that can settle on the surface of the body of invertebrates and other substrates. Mereschkowsky (1881) described this species as epibiont on hydroids Sertularia sp. from the Black Sea near Livadia (Yalta). The species was reported attached on hydroids Obelia commissuralis McCrady, 1859 and O. geniculata (Linnaeus, 1758) from Woods Hole, USA ( Root 1922). This species was found from Mediterranean Sea (Port Said, Egypt) and at the Atlantic coast of the USA ( Dovgal 2013). The species was registered in the Black Sea on algae Cladophora sp. near Sevastopol and on Cladophora sp. and crab Pachygrapsus marmoratus (Fabricius, 1787) from the coast of the Karadag Natural Reserve (Crimea) ( Dovgal 2013). It was observed from harpacticoid copepods Amphiascella subdebilis (Willey, 1935) , Haloschizopera pontarchis Por, 1959 , Cletodes tenuipes Scott, 1896 and Enhydrosoma longifurcatum Sars, 1909 in the hypoxic zone of the Black Sea by Sergeeva & Dovgal (2014).

This is the first report of this species from the Arabian Sea and the Indian Ocean.

Figures

FIGURE 2. A. Paracineta livadiana (Mereschkowsky, 1881) attached on nematode host (arrow indicating ciliate), B. Magnified view of Paracineta livadiana, C. Loricophrya bosporica Sergeeva & Dovgal, 2016 attached on nematode host (arrow indicating ciliate), D. Magnified view of Loricophrya bosporica.