Operculina discoidalis d’Orbigny, 1826

Symphonia, Tabita K. & Senthil, Nathan D., 2019, Taxonomic notes on Recent Foraminifera from the Continental Shelf-Slope Region of Southwestern Bay of Bengal, East Coast of India, Palaeontologia Electronica (55 A) 22 (3), pp. 1-89 : 45-46

Operculina discoidalis d’Orbigny, 1826

Figure 12.11

1826 Nummulina (Assilina) discoidalis d’Orbigny , p. 296, no. 88.

2011 Operculina discoidalis (d’Orbigny) ; Hohenegger, p. 659, fig. 2a.

2012 Operculina discoidalis (d’Orbigny) ; Debenay, p. 228.

Description. Test very flat, discoidal, wall calcareous, finely perforate, surface distinctly ornamented with granular pustules; chambers not separate; coiling involute initially, later nearly evolute; periphery rounded with a distinct keel, sutures slightly raised, limbate, marked with rows of pustules, slightly depressed at the periphery.

Figures

FIGURE 12. 1-2, Lobatula lobatula (Walker and Jacob, 1798) in dorsal view (scale equals 400 μm) (1) and in ventral view (scale equals 100 μm) (2). 3-4, Cymbaloporetta bradyi (Cushman, 1915) in dorsal view (scale equals 200 μm) (3) and in ventral view (scale equals 300 μm) (4). 5, Riminopsis asterizans (Fichtel and Moll, 1798) in dorsal view (scale equals 200 μm). 6-7, Hansenisca soldanii (d’Orbigny, 1826) in dorsal view (scale equals 200 μm) (6) and in ventral view (scale equals 100 μm) (7). 8, Operculina ammonoides (Gronovius, 1781) in dorsal view (scale equals 1 mm). 9, Operculina bartschi Cushman, 1921 in dorsal view (scale equals 1 mm). 10, Operculina complanata (Defrance, 1822) in dorsal view (scale equals 500 μm). 11, Operculina discoidalis d’Orbigny, 1826 in dorsal view (scale equals 500 μm). 12, Operculina elegans Cushman, 1921 in dorsal view (scale equals 1 mm). 13, Operculina granulosa Leymerie, 1846 in dorsal view (scale equals 500 μm). 14, Operculina hardiei d’Archiac and Haime, 1853 in dorsal view (scale equals 500 μm). 15, Heterostegina depressa d’Orbigny, 1826 in dorsal view (scale equals 300 μm). 16, Planostegina operculinoides (Hofker, 1927) in dorsal view (scale equals 1 mm). 17-19, Pileolina patelliformis (Brady, 1884) in dorsal view (scale equals 200 μm) (17); in lateral view (scale equals 100 μm) (18); and in ventral view (scale equals 100 μm) (19). 20, Planogypsina acervalis (Brady, 1884) in dorsal view (scale equals 500 μm). 21, Sphaerogypsina globulus (Reuss, 1848) in dorsal view (scale equals 300 μm).