Ciliophora

Sergeeva, Nelli G. & Mazlumyan, Sofia A., 2015, Deep - water hypoxic meiobenthic Protozoa and Metazoa taxa of the Istanbul Strait’s (Bosporus) outlet area of the Black Sea, Ecologica Montenegrina 2 (3), pp. 255-270 : 260-261

1.2. Ciliophora

Three species of commensal ciliates Cothurnia maritima Ehrenberg 1838 on oligochaete Tubificoides sp. ; Paracineta livadiana (Mereschkowsky 1881) and Corynophrya lyngbyi (Ehrenberg 1834) on harpacticoid copepods Amphiascella subdebilis (Willey 1935) , Haloschizopera pontarchis Por 1959 , Cletodes tenuipes Scott 1896 and Enhydrosoma longifurcatum (Sars 1909) were found in the Bosporus region of the Black Sea deep-water (200 and 248 m depths) under hypoxic/anoxic conditions ( Sergeeva & Dovgal 2014).

Vertical distribution of the free-living benthic Ciliophora in the Bosporus area at the depths from 120 to 300 m was characterized by two peaks of abundance at 103 and 250 m water depth ( Fig. 5).

In the Bosporus area Ciliophora was registered in all layers of the bottom sediment. The most inhibited are the upper layers (0–2 cm) of sediment ( Fig. 6 ). Ciliates abundance peaks can be connected with food accumulations. Different forms were present, including moving and attached forms, totally more than 30 species (morphotypes).

3 50

10 40

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indiv 30 20

, 10

N

0

75 82 88 103 122 162 190 250 300

De pth, m

It is known that the top peak of ciliates abundance usually was located in the region of the hydrogen sulfide border. The most number of benthic ciliates morphotypes was registered at the 250 m depth, in the region of lower peak of abundance.

0-1cm 1-2 cm 2-3 cm 3-4 cm 4-5 cm 5-7 cm Depth (m)

Earlier the bathymetric distribution of the benthic ciliates at depths from 120 to 2075 m near the Dnieper Canyon and the Sorokin Trough (eastern part of the Black Sea ) was described from samples of near bottom water, sediment surface detritus, and the upper layer (0–1 cm) of sediment. Hydrogen sulfide was registered beginning from 160– 170 m. The ciliates found in mentioned samples were the representatives of genera Chilodonella Strand 1928 , Trachelocerca Ehrenberg 1834 , Tracheloraphis Dragesco 1960 and Loxophyllum Dujardin 1841 . At the same time more than 30 morphological species were recognized among mentioned materials (Sergeeva & Zaika 2008 ). The peaks of ciliate abundances were registered at depths of 120, 160– 190, and 240 m in the same region (Sergeeva et al. 2008). Average abundance peak coincides with the depths of hydrogen sulfide appearance. Besides, according to the data available, at the same depths there are pelagic peaks of intensity of bacterial chemosynthesis and bacteria production. Therefore ciliates abundance peaks can be connected with food accumulations. The most number of ciliates morphotypes (8) was at the 240 m depth, in the region of the lower peak of abundance.

Figures

Figure 6. Proportion of the Ciliophora inhabiting different sediment layers along the depth gradient at the Bosporus outlet area of the Black Sea.