Amphora cf. commutata Grunow, 1880

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 : 133-134

Amphora cf. commutata Grunow in Van Heurck (1880: pl. 1, fig. 14) ( Fig. 69 )

References: Witkowski et al. 2000, p. 134, pl. 169, figs 5–7; Sato et al. 2013, p. 229, Figs 5–12 .

Features: Length 70–95 μm, width 12–16 μm, striae 6–7 in 10 μm on the dorsal side.

Description: Valves linear lunate with ventrally bent rostrate apices. Dorsal margin weakly arched, ventral margin slightly curved. Raphe weakly arcuate, more close to ventral margin, proximal endings bent towards dorsal side. Central area absent.

Remarks: This species looks similar to the illustration of A. commutata presented in Witkowski et al. (2000), but slightly different in striae density (9–13 versus 6–7 in 10 μm for this species). In the observed specimens striae run deeper from the dorsal towards ventral margins. The same species was reported by Al-Kandari et al. (2009, pl. 66, fig. A) as Amphora sp.2 from Kuwait coastal water.

Ecology and Distribution: Amphora commutata is a brackish water species. Common in Basra corals.

Figures

FIGURES 62–74. Marine benthic diatoms in coral reefs off Basra.Fig. 62. Pleurosigma diverse-striatum, Fig. 63. Pleurosigma strigosum, Figs 64, 65. Plagiotropis lepidoptera, Fig. 66. Stauroneis sp., Fig. 67. Amphora arcuata, Fig. 68. Amphora arenaria, Fig. 69. Amphora cf. commutata, Fig. 70. Amphora cingulata, Fig. 71. Halamphora coffeaeformis, Fig. 72. Halamphora costata, Figs 73,74. Amphora graeffeana.

FIGURES 2–10. Marine benthic diatoms in the coral reefs off Basra. Fig. 2. Cyclotella striata, Fig. 3. Cyclotella stylorum, Fig. 4. Tryblioptychus cocconeiformis, Figs 5, 6. Podosira stelliger, Fig. 7. Paralia sulcata, Fig. 8. Coscinodiscus centralis, Fig. 9. Coscinodiscus marginatus, Fig. 10. Triceratium robertsianum.

FIGURES 11–20. Marine benthic diatoms in the coral reefs off Basra. Fig. 11. Actinocyclus curvatulus, Fig. 12. Actinocyclus octonarius, Fig. 13. Lyrella abrupta, Fig. 14. Lyrella clavata, Fig. 15. Lyrella hennedyi, Fig. 16. Lyrella hennedyi var. subcarinata, Fig. 17, Lyrella spectabilis, Fig. 18. Petroneis granulata, Fig. 19. Petroneis marina, Fig. 20. Petroneis sp.