Quinqueloculina
Introduction '''''Quinqueloculina''''' is a genus of foraminifera in the family Miliolidae.As with all miliolids the test of ''Quinqueloculina'' is composed of imperforate, porcelaneous calcite, often giving them a yellowish tint. As with the Miliolidae, the chambers are arranged in various planes, with two chambers per whorl. In ''Quinqueloculins'' the chambers are in planes set 72 degrees apart, but successive chambers are in planes separated by 144 degrees. The name ''Quinqueloculina'' comes from ''quinque'', the Latin for five. In ''Quinqueloculina'' five chambers are exposed to view on the outside, although the earlier three are sandwiched between the later two, one on one side, two on the other. Chambers are generally long and tubular, normally without integral floors, that function made by the underlying chamber.Some 30 or more species of ''Quinqueloculina'' have been named. ''Quinqueloculina'' is found in abundance around the coasts of the UK. High concentrations of one species of ''Quinqueloculina'' within the Celtic Sea are interpreted as a seasonal indicator of strong vertical mixing in that water body.In an experiment, trends in diversity, abundance and taxonomic composition of live foraminiferal assemblages were analyzed to replicate corer samples collected at the Porcupine Abyssal Plain over a thirteen-year period. Conclusions found that the miliolid ''Quinqueloculina'' sp. was virtually absent in multicore samples from 1989 to 1994, peaked in September 1996 (22%) when degraded phytodetritus was present on core surfaces, was less common in March 1997, and thereafter was relatively uncommon. However, horizontally sliced box-core samples revealed that large specimens were more abundant in March 1997, and also were concentrated in deeper sediment layers, than in September 1996.It is suggested that ''Quinqueloculina'' sp. migrated to the sediment surface in response to a 1996 flux event, grew, and reproduced, before migrating back into deeper layers as the phytodetrital food became exhausted. Overall, the abyssal time-series revealed decadal-scale changes among shallow-infaunal foraminifera, more or less coincident with changes in the megafauna, as well as indications of shorter-term events related to seasonally-pulsed phytodetrital inputs.
See also * List of prehistoric foraminiferans
References * Cushman Joseph A 1950  Foraminifera, their classification and economic use (4th ed)  Harvard University Press, Cambridge Mass * Alfred R. Loeblich Jr and Helen Tappan, 1964.Sarcodina Chiefly "Thecamoebians" and Foraminiferida; Treatise on Invertebrate Paleontology, Part C Protista 2.Geological Society of America and University of Kansas Press. * ____ 1988.Forminiferal Genera and their Classification. E-book
Further reading
External links *  Quinqueloculina on www.biolib.cz*  Quinqueloculina on www.foraminifera.eu