Navicula directa (W. Smith) Ralfs

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 : 127-128

Navicula directa (W. Smith) Ralfs in Pritchard (1861: 906) ( Fig. 50 )

References: Hendey 1964, pl. 30, fig. 22; Poulin & Cardinal 1982, fig. 10; Stidolph et al. 2012, pl. 12, figs 91, 92; Witkowski et al. 2000, p. 275, pl. 129, fig. 1, pl. 133, figs 10–12,?13;

Features: Length 73–90 μm, width 8–10 μm, striae 8–11 in 10 μm.

Description: Valves linear lanceolate with apiculate apices. Raphe branches straight, ending centrally in simple pores, slightly deflected in the same direction. Axial area narrow, central area transapically dilated. Transapical striae parallel throughout.

Ecology and Distribution: A cosmopolitan marine species. Previously reported from Kuwait ( Hendey 1970; Al-Yamani & Saburova 2011) and from Southern Iraq ( Al-Handal 2009). Common in Basra corals.

Figures

FIGURES 38–51. Marine benthic diatoms in coral reefs off Basra. Fig. 38. Diploneis gemmatula, Fig. 39. Diploneis nitescens, Fig. 40. Diploneis smithii, Figs 41, 42. Diploneis weissflogii, Fig, 43. Diploneis sp., Fig. 44. Navicula arenaria, Fig. 45. Navicula cancellata, Figs 46–48. Navicula carinifera, Fig. 49. Navicula cf. cincta, Fig. 50. Navicula directa, Fig. 51. Navicula distans.