Entopyla ocellata (Arnott) Grunow, 1862

Al-Handal, Adil Y., Torstensson, Anders & Wulff, Angela, 2022, Revisiting Potter Cove, King George Island, Antarctica, 12 years later: new observations of marine benthic diatoms, Botanica Marina (Warsaw, Poland) 65 (2), pp. 81-103 : 89

Entopyla ocellata (Arnott) Grunow ( Figures 37, 38 , 109– 111 )

References: (Al-Handal and Wulff 2008b, p. 427, figs. 57– 62, 65; Desikachary 1988, p. 11, pl. 584, figs. 10, 11).

Description: Length 48–75 µm, width 10–16 µm, striae 4–6 in 10 µm.

Remarks: This species is characterized by having large and wide apical pore fields occupying two thirds of the concave valve face ( Figures 109, 110 ). A very narrow sternum (not visible under LM) runs from pole to pole. Two rimoportula open externally as small, elongated openings located centrally under each pore field and internally as large crescent-like openings located transversely with short stalks ( Figure 111 ) which are very characteristic for this species.

Ecology and distribution: A marine epiphytic or benthic species. Widely distributed as epiphyte in King George Island (Al-Handal and Wulff 2008b). Frequent in the present material.

Figures

Figures 27–38: Marine benthic diatoms in Potter Cove, King George Island, Antarctica, summer 2015. (27) Corethron pennatum. (28) Fragilaria striatula. (29) Synedropsis sp. (30) Licmophora antarctica. (31–32) Licmophora belgicae. (33) Licmophora gracilis. (34) Licmophora luxuriosa. (35) Thalassionema nitzschioides. (36) Rhabdonema arcuatum. (37, 38) Entopyla ocellata.

Figures 107–112: SEM images of the marine benthic diatoms in Potter Cove,King George Island, Antarctica,summer 2015.(107,108) Porosira glacialis, internal valve view showing the single marginal labiate process. (109–111) Entopyla ocellata, (109, 110) external valve view showing the wide and superficial apical porefield which occupies large area of valve face, (111) internal valve structure showing the narrow and crescent-like rimoportula openings (white arrows). (112) Navicula sp. 2.