Abstract
Foraminiferans with soft, flexible tests have been recorded rarely in deep-sea environments. However, detailed examination of meiofaunal samples from 1330 m in the Porcupine Seabight (southwest of Ireland) has revealed an abundant and diverse assemblage of these forms, many of which are unilocular with a flask-like morphology. Two groups are distinguished by the nature of the test wall. This is either transparent and almost completely proteinaceous (suborder Allogromiina) or more or less translucent and composed of a thin organic layer overlain by agglutinated particles (suborder Textulariina, superfamily Astrorhizacea, family Saccamminidae). Together, these groups make up 9–27 % of the total foraminiferal fauna and are represented by > 40 putative species. Individual subsamples of 3.46 cm2 surface area yielded 16–28 species. Only one species, Nodellum membranacea (BRADY), has been identified; the remainder are undescribed. The assemblage is dominated by small individuals; most allogromiids are < μm long and most saccamminids < 200 μm long. It seems likely that these delicate organisms are more abundant in deep-sea environments than has been recognized hitherto.
