Euplotes dammamensis, Chen & Zhao & Al-Farraj & Al-Quraishy & El-Serehy & Shao & Al-Rasheid, 2013

Chen, Xiangrui, Zhao, Yan, Al-Farraj, Saleh A., Al-Quraishy, Saleh A., El-Serehy, Hamed A., Shao, Chen & Al-Rasheid, Khaled A. S., 2013, Taxonomic Descriptions of Two Marine Ciliates, Euplotes dammamensis n. sp. and Euplotes balteatus (Dujardin, 1841) Kahl, 1932 (Ciliophora, Spirotrichea, Euplotida), Collected from the Arabian Gulf, Saudi Arabia, Acta Protozoologica 52 (2), pp. 73-89 : 74-76

Euplotes dammamensis n. sp. ( Figs 1–36 ; Tables 1, 2)

Diagnosis. Marine Euplotes with 10 conspicuous dorsal ridges, 100–170 × 80–120 μm in vivo. Adoral zone comprising about three-quarters of the total cell length, with about 48 membranelles; consistently 10 frontoventral, five transverse and two marginal cirri, and, generally, two or three caudal cirri, with second cirrus prolonged significantly; 11 dorsal kineties with about 16 dikinetids in mid-dorsal row. Macronucleus variable in shape, anterior part typically C-shaped with posterior part distorted.

Type location. Isolated from the Arabian Gulf (26°33′07″N, 50°01′30″E) on 16 December 2011. Salinity about 65‰ and water temperature about 17°C.

Type specimens. The slide (registration number: CXR- 20111216 -20-01) containing the holotype specimen ( Figs 8, 9 , 27, 28 ) and one paratype slide (registration number: CXR- 20111216 -20-02) with protargol-impregnated specimens have been deposited in the Laboratory of Protozoology , Ocean University of China, Qingdao .

Figures

Figs 1–9. Euplotes dammamensis n. sp. in vivo (1–7) and after protargol impregnation (8, 9). 1, 2 – ventral views of different individuals, arrows indicate the longest caudal cirrus; 3 – dorsal view, showing the conspicuous ridges; 4 – lateral view; 5 – frontoventral cirri, arrows indicate the cortical granules around the cirri; 6 – apical view of the cortical granules distributed on the dorsal side; 7 – lateral view of the cortical granules; 8, 9 – ventral and dorsal views of the same specimen, showing the general infraciliature and the micronucleus (arrow). AZM – adoral zone of membranelles, CC – caudal cirri, DK – dorsal kineties, FVC – frontoventral cirri, MC – marginal cirri, PM – paroral membrane, TC – transverse cirri, 1–11 – dorsal kineties. Scale bars: 50 μm.

Figs 10–18. Morphogenesis and macronucleus of Euplotes dammamensis n. sp. after protargol impregnation. 10–12 – different shapes of macronucleus; 13, 14 – ventral and dorsal views of the same specimen at an early stage of morphogenesis, showing the appearance of frontoventral-transverse cirral anlagen (arrowheads), the developing oral primordium (arrow) and the proliferation of basal bodies in the dorsal kineties (double-arrowheads); 15, 16 – ventral and dorsal views of the same specimen showing the marginal cirral anlagen (arrowheads) and the newly formed dorsal kinety anlagen (double-arrowheads); 17, 18 – ventral and dorsal views of the same specimen showing the migratory cirral anlage in the proter (arrowhead) and the longer dorsal kinety anlagen (double-arrowheads).

Figs 19–28. Photomicrographs of Euplotes dammamensis n. sp. in vivo (19–25) and after protargol impregnation (26–28). 19, 20 – ventral views of different specimens, arrowheads in (19) to show the ventral ridges; 21 – dorsal view, arrowheads point to the dominant dorsal ridges; 22 – lateral view; 23 – ventral view of the posterior end, arrowhead marks the longest caudal cirrus; 24 – detailed dorsal view, arrowheads point to the apical view of the granules around the dorsal brush; 25 – arrowheads to show the lateral view of granules around the dorsal brush; 26 – arrow indicates the curved C-shaped macronucleus; 27, 28 – infraciliature on the ventral and dorsal sides, arrowheads indicate the dorsal kineties. Scale bars: 50 μm.

Figs 29–36. Photomicrographs of Euplotes dammamensis n. sp. during binary division after protargol impregnation. 29, 32 – ventral and dorsal views of a specimen at an early stage of morphogenesis to show the frontoventral-transverse cirral anlagen (29, arrowheads) and denote the parental dikinetids (32, arrowheads); 30, 33, 34 – ventral and dorsal views of a specimen at a slightly later stage of morphogenesis, to show the frontoventral-transverse cirral anlagen developed and broadened (30), the newly formed dorsal kineties anlagen (33, arrowheads) and the marginal anlagen (34, arrowheads); 31, 35, 36 – ventral and dorsal views of a specimen at middle-stage to show the rightmost frontoventral-transverse cirral anlagen (31, arrowheads), the migratory cirral anlage in the proter (31, double-arrowhead), the marginal cirral anlagen (31, arrows), the dorsal kineties anlagen (35, arrowheads) and the replication bands (36, arrowheads).