Diploneis chersonensis (Grunow) Cleve (1894: 91)

Al-Handal, Adil Y., Thomas, Evan W. & Pennesi, Chiara, 2018, Marine benthic diatoms in the newly discovered coral reefs, off Basra coast, Southern Iraq, Phytotaxa 372 (2), pp. 111-152 : 124

Diploneis chersonensis (Grunow) Cleve (1894: 91) ( Fig. 36 )

References: Peragallo & Peragallo1897 –1908, pl. 19, fig. 9; Hustedt 1931 –1959, fig. 1088; Hendey, 1964, p. 227, pl. 32, figs 7, 8, 1970, p. 142, pl. 5, fig. 48; Witkowski et al. 2000, p. 184, pl. 86, fig. 10; Lobban et al. 2012, pl. 44, figs 1‒4.

Features: Length 50–78 μm, width 15–30 μm, striae 9–10 in 10 μm.

Description: Valves panduriform, constricted at the center with rounded apices. Raphe fissures straight with rounded central nodule. Axial area narrow with linear longitudinal canals. Transapical striae parallel at the center, strongly radiate near the apices.

Remarks: D. chersonensis is characterized by having a square central area bordered by four chambers on each side; the outer chambers are longer than the central ones. In the observed specimens, longer chambers are visible but the shorter ones are not but can be observed by changing focus of the microscope field.

Ecology and Distribution: Widely distributed marine species. Previously reported from the Gulf ( Hendey 1970, Al-Yamani & Saburova 2011). Frequent in Basra corals.

Figures

FIGURES 21–37. Marine benthic diatoms in coral reefs off Basra. Fig. 21. Mastogloia quinquecostata, Fig. 22. Cocconeis latecostata, Fig. 23. Berkeleya scopuloru, Figs 24, 25. Climaconei sp. Fig. 26. Parlibellus rhombiformis, Fig. 27. Parlibellus sp., Fig. 28. Biremis ambigua, Fig. 29. Fallacia forcipata, Fig. 30. Fallacia nummularia, Fig. 31 Fallacia sp., Fig. 32. Progonoia musca, Fig. 33. Caloneis elongata, Fig. 34. Caloneis liber, Fig. 35. Diploneis cf. interrupta, Fig. 36. Diploneis chersonensis, Fig. 37. Diploneis fusca.