Cornuloculina sp.A

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Mynd: Guðmundur Guðmundsson

Cornuloculina sp.A (Plesiotypes 1 & 2 from sample Bioice3282: depth 1830 m; bottom water temp. 2,54°C; loc. 62,800°N, -16,256°W Dec.Degr.)

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Mynd: Guðmundur Guðmundsson

Dreifing tegundar eftir dýpi, seltu og sjávarhita, innan þess breytileika sem allar sýnatökustöðvar ná yfir, sýnt sem heildarspönn lóðréttra ása. Gögn úr botndýraverkefninu „BIOICE“. (ENGLISH – Occurrence zone of the species within the range of water depth, temperature, and salinity, spanned by the "Bioice" samples; demarcated by respective y-axes.)

Almennt

Cornuloculina sp.A

Description: Test is thin and semi-transparent. The embryonic apparatus consists of a globular proloculus and planispirally coiled undivided tube of about 2-3 windings (cornuspiran stage), followed by 9 - 10 tubular, planispiral chambers (spiroloculine stage), each of about a half to one coil in length; later the tubular chambers become successively shorter and wider, resulting finally in several flaring chambers. The inner margin of the chambers is lined with a thin semi-translucent flange, shown as a shaded area in the figure; the flange is greatly reduced in the flabelliform chambers. The aperture is a simple round opening in the initial spire, and an elongated slit in the flabelliform chambers, confined to the outer margin only, i.e. not extending to the inner spire as in Cornuspira. Seventeen specimens and fragments of this species were picked from one of the 1031 BIOICE samples that were checked for forams. In addition the species has been found in one additional sample, located outside the enclosed map further south on the Reykjanes Ridge.   

Diagnosis: Resembles superficially some Cornuspira species in general shape, but differs in having an early spiroloculine stage and a flange separating successice worls.

Gudmundur Gudmundsson, IINH (gg@ni.is)

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Útbreiðsla Cornuloculina sp.A (Bioice samples, red dots; miscellaneous IINH samples, blue dots)

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