Asterigerinata mamilla (Williamson, 1858)

Camacho, S, Moura, D, Connor, S, Scott, DB & Boski, T, 2015, Taxonomy, ecology and biogeographical trends of dominant benthic foraminifera species from an Atlantic-Mediterranean estuary (the Guadiana, southeast Portugal), Palaeontologia Electronica 52 (4), pp. 1-37 : 24-25

Asterigerinata mamilla (Williamson, 1858)

Figure 5.2-5.3

1858 Rotalia mamilla Williamson : p. 54, pl. 4, figs. 109-111.

1971 Asterigerinata mamilla (Williamson) ; Murray, p. 141, pl. 59, figs. 1-6.

1974 Discorbis mamilla (Williamson) ; Colom, p. 124, fig. 21, f -i and o -s.

1995 Asterigerinata mamilla (Williamson) ; Lévy, Mathieu, Poignant, Rosset-Moulinier, Ubaldo and Lebreiro, p. 46, pl. 10, fig. 10.

2004 Eoeponidella pulchella ( Parker, 1952) ; Diz, Francés, Costas, Souto and Alejo, p. 273, pl. 2, fig. 14.

2012 Asterigerinata mamilla (Williamson) ; Milker and Schmiedl, p. 111, figs. 24.21-24.24.

Morphological description. Calcareous wall, test planoconvex, trochospiral and conical in peripheral view; spiral side is convex and evolute; umbilical side is involute; chambers increasing rapidly in breadth and becoming broad; sutures are curved and oblique; on the umbilical side only the five chambers of the final whorl are visible; sutures are slightly depressed; both sides are perforate with larger pores on the spiral; aperture is a low interiomarginal, umbilical arch at the base of the final chamber.

Occurrence. Common species (10-20%) in the biocenosis; more abundant at the lower estuary; higher densities during winter.

Figures

FIGURE 5. Scanning electron and light microscope micrographs of the foraminifera specimens. Scale bar equals 100 µm. 1- Lamarckina haliotidea (Heron-Allen and Earland, 1911) ventral view; 2-3- Asterigerinata mamilla (Williamson, 1858); 2- dorsal view; 3- ventral view; 4-5- Discorbis sp.; 4- dorsal view; 5- ventral view; 6-7- Helenina anderseni (Warren, 1957); 6- dorsal view; 7- ventral view; 8- Haynesina depressula (Walker and Jacob, 1798) side view; 9- Haynesina germanica (Ehrenberg, 1840) side view; 10- Elphidium advenum (Cushman, 1922) side view; 11- Elphidium excavatum (Terquem, 1875) side view; 12-15- Elphidium wiliamsoni Haynes, 1973; 12- side view in light microscope image; 13- side view in scanning electron image; 14- profile view in scanning electron image; 15- side view of a smaller specimen in scanning electron image; 16-18- side view of different size Elphidium gerthi Van Voorthuysen, 1957; 19-21- Elphidium oceanensis (d’Orbigny, 1826); 19- side view in scanning electron image; 20- profile view in scanning electron image; 21- side view in light microscope image; 22- Elphidium poeyanum (d’Orbigny, 1826) side view; 24-27- Ammonia sp1; 24- dorsal view; 25- profile view; 26- ventral view; 27- dorsal view in light microscope image; 28-31- Ammonia sp2 (Ammonia aberdoveyensis Haynes, 1973); 28- dorsal view; 29- profile view; 30- ventral view; 31- dorsal view in light microscope image; 32-35- Ammonia sp3 (Ammonia aberdoveyensis Haynes, 1973); 32- dorsal view; 33- profile view; 34- ventral view; 35- dorsal view in light microscope image.