Apatite Particles in the Test Wall of the Large Agglutinated ForaminiferBathysiphon Major(Protista)

Abstract

In the North Atlantic, the tubular agglutinated foraminifer Bathysiphon major occurs at bathyal depths off the coasts of North Carolina and north-west Africa. Apart from its large size (up to almost 10 cm long), the most distinctive feature of this species is the appearance of the test wall which has a sooty black outer layer, about 20μm thick, overlying a much thicker layer, pure white in colour and consisting of sponge spicules and small quartz grains. The black layer is composed of irregularly shaped, plate-like particles, 1–25 (xm in size. The nature and composition of these particles has been studied using light and electron microscopy, x-ray microanalysis, electron diffraction analysis and infrared spectroscopy. The particles contain calcium and phosphorous and have electron diffraction patterns and infrared spectra consistent with a hydroxyapatite composition. Minor amounts of iron are probably responsible for their black colour. We believe that this represents the first report of apatite-like (phosphorite) particles occurring in the test of an agglutinated foraminifer. The particles are most likely to originate as phosphorite grains which are agglutinated by the foraminifer, although the possibility of authigenic precipitation cannot be eliminated. The function of the outer black layer is unknown.

Selective agglutination of tourmaline grains by foraminifera in a deep-water flysch environment (Eocene Hieroglyphic beds, Silesian Nappe, Polish Outer Carpathians)

“…On the other hand, Recurvoides, Trochamminoides and Paratrochamminoides, which oc cur in sim i lar num bers in the as sem blage, se lect tourma line grains much less of ten in spite of the fact that, be ing actively mo bile on the sur face and within sed i ment, they have eas ier ac cess to this test-build ing de tri tal com po nent. Also, rela tively low pro por tion of Bathysiphon in cor po rate tour ma line grains, but they ag glu ti nate in or ganic par ti cles and var i ous non-quartz min eral com po nents rel a tively of ten (Dick, 1928;Bruce et al, 1981;Gooday nad Claugher, 1989;Gooday et al, 1995bGooday et al, , 2002Cole and Val en tine, 2006).…”

“…Be sides quartz, the fol low ing in or ganic de tri tal com po nents are ob served in the foraminifera test walls: cal cite, ar agon ite, do lo mite, glauconite, feld spars, micas, pyroxene, hornblende, mag ne tite, py rite as well as other heavy min er als, e.g. to paz, il men ite, mag ne tite, rutile, zir con, min er als rep re sent ing the gar net group, ap a tite, amhibole, and phillipsite (e.g., Heron-Allen, 1915;Switzer and Boucot, 1955;Weston, 1984;Höfling, 1988;Gooday et al, 1995b;Bartholdy et al, 2005;Makled and Langer, 2009;Mancin et al, 2012 and ci tations therine). Also shocked di a mond grains (Kaminski et al, 2008) and vol ca nic glass frag ments (Switzer and Boucot, 1955;Hess et al, 2000) were spo rad i cally ob served among the ag gluti nated grains.…”

The Crystallography and Possible Origin of Barium Sulphate in Deep Sea Rhizopod Protists (Xenophyophorea)

“…Like some granellae, a few have a central hole. Some agglutinated Foraminifera are able to select particular mineral grains from the sediment and concentrate them in the test (Gooday et al, 1995). A similar process could account for the presence of barite crystals in the protoplasm of xenophyophores, although it is not obvious why they should be taken into the protoplasm rather than incorporated into the test.…”

Fractal analysis highlights analogies in arenaceous tubes of Sabellaria alveolata (Metazoa, Polychaeta) and agglutinated tests of foraminifera (Protista)

“…Grains are either selected or randomly picked from the water column or bottom sediment, then manipulated in three dimensions and cemented to form the agglutinated wall. This ability has been observed in unicellular organisms, such as tintinnids, testate amoebae and agglutinated foraminifera [e.g., [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], as well as in different multicellular groups, such as arthropods (tubicolous amphipods and tanaids, as well as caddisflies) and polychaete annelids [5,[21][22][23][24][25][26][27][28][29].…”