Donkinia carinata (Donkin) Ralfs (1861: 921)

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 : 131

Donkinia carinata (Donkin) Ralfs (1861: 921) ( Fig. 61 )

References: Pritchard 1861, pl. 40; Peragallo & Peragallo 1908, pl. 36, fig. 15; Hartley et al. 1996, pl. 290; Hein et al. 2008, p. 54, pl. 29, fig. 2. Kim et al. 2017, figs 5I‒P.

Features: Length 80–120 μm; width 18–25 μm, striae fine, 22–24 in 10 μm.

Description: Valves linear- lanceolate with acutely rounded apices. Raphe branches sigmoid, raised as ridge upon valve margin. Central nodule small and rounded. Striae appear in equidistant oblique and transverse rows.

Remarks: Observed specimens appeared with striae slightly denser than previously reported from the Gulf ( Hendey 1970; Al-Yamani & Saburova 2011) who observed 18–20 in 10 μm.

Ecology and Distribution: A marine littoral species, mostly on muddy sediments. Frequent in Basra corals.

Figures

FIGURES 52–61. Marine benthic diatoms in coral reefs off Basra. Fig. 51. Navicula distans., Fig. 52. Navicula kariana var. frigida, Fig.53. Navicula transistantioides, Fig.54. Navicula sp., Fig. 55.Seminavis sp., Fig.56.Trachyneis antillarum, Fig.57.Trachyneis aspera, Fig. 58. Trachyneis clepsydra, Fig. 59. Trachyneis debyi, Fig. 60. Tracyneis velata, Fig. 61. Donkinia carinata.