Tetramphora ostrearia (Brébisson) Mereschkowsky (1903: 54)

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 : 138

Tetramphora ostrearia (Brébisson) Mereschkowsky (1903: 54) ( Figs 85, 86 )

References: Podzorski & Håkansson, 1987, Pl. 16, figs 1, 2; Witkowski et al., 2000, p. 146, pl. 170, fig. 23; Hein et al., 2008, pl. 21, figs 2, 7; pl. 22, fig. 1. (All as Amphora ostrearia Brébisson ex Kützing 1849: 94 ).

Features: Length 40–58 μm, width 8–10 μm, striae 14–16 in 10 μm on the dorsal side, 18–20 on the ventral side.

Description: valves dorsiventral, semi-eliptic with acutely rounded apices. Dorsal margin arched, ventral margin straight. Axial area narrow, central area expands towards dorsal margin forming narrow fascia. Raphe biarcuate, proximal endings bent dorsally. Striae on dorsal side distinctly punctate.

Remarks: Observed specimens appeared rather smaller with slightly denser striae than those reported from the Gulf (Al-Yamani & Saburova 2011) or elsewhere ( Witkowski et al. 2000). Several varieties of Amphora ostrearia have been described based on the number of striae bands on the ventral margin and the shape or structure of the stauros.

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

Figures

FIGURES 75–90. Marine benthic diatoms in coral reefs off Basra. Figs 75, 76. Amphora grevilleana, Figs 77, 78. Amphora janischii, Figs 79, 80. Amphora maletracta var. constricta, Fig. 81. Amphora marina, Fig. 82. Amphora mexicana, Figs 83, 84. Amphora ocellata, Figs 85,86. Tetramphora ostrearia, Figs 87,88. Tetramphora rhombica, Fig. 89. Amphora spectabilis, Fig. 90. Amphora sp.