Parapores

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Fig. 1. Fistulose chamberlets. All specimens from the Gulf of Aqaba, Red Sea, Recent. A-C: Sahulia kerimbaensis (Said). A: Detail of an edge view, SEM graph; B: side view, X-ray graph, black background removed. Note the narrowness and the irregularity of the fistulose chamberlets in this species. C: edge view, SEM graph. D-H: Spirotextularia floridana (Cushman). D: paraporous partition separating the chamber lumen from a fistulose chamberlet. SEM graph. E: Detail of sectioned paraporous partition. SEM graph. Note the organic lining that closes off the parapores from the chamber lumen. SEM graph. F: Shell fragment broken in a direction perpendicular to the shell axis, showing paraporous partition between the chamber lumen and the fistulose chamberlet. SEM graph. G: Lateral view, X-ray graph. H: lateral view of an entire specimen. SEM graph. Note the spiral arrangement of the nepionic chambers. a: aperture; af: apertural face; ch: chamber lumen; f: foramen; fis: fistulose chamberlet; OL: organic lining; pp: parapores; ppa: paraporous partition; pr: proloculus; pv: pavement; s: septum; (Hottinger, 2006; fig. 51)[1] CC/BY-NC-SA)
Fig. 2.Agglutination in foraminiferan walls; Gulf of Aqaba, Red Sea; Recent. A-C: Textularia sp. C in Hottinger et alii, 1993. A: Lateral view showing coarse grains producing a rugged shell surface exept on apertural face. SEM. B: axial thin section of the biserial test showing distribution of agglutinated grains within the shell walls. Light microscope, transparent light. C: Detail from another specimen showing parapore texture of wall and its relation to the agglutinated grains. Transmitted light. D-G: Agglutinella sp., an agglutinating, porcelaneous miliolid. D: lateral view showing coarse agglutination at the shell's suface. E: apertural view showing large aperture with a porcelaneous peristomal rim and a miliolid tooth. SEM. F-G: Schlumbergerina alveoliniformis (Brady), thin sections in the - and perpendicular to the - apertural axis, showing early growth stages without apparent agglutination and a very thin basal layer coating the rugged surface of adult chambers of the previous whorl. Transmitted light; a: aperture; bl: basal layer; f: foramen; mt: miliolid tooth; pp: parapores; pr: proloculus; s: septum; sut: (chamber) suture; tph: trematophore' (Hottinger, 2006; fig. 6)[2] CC/BY-NC-SA)


Definition

  • according to Hottinger (2006):

PARAPORES (canaliculi; pseudopores, pars auct.) is in agglutinated foraminifera: straight to tortuous tubular spaces, round to polygonal in section, more or less normal to the test surface, coated and closed off internally by the organic lining. May be branching and anastomosing and - usually - restricted to the inner wall-layer, thus ending blindly beneath an outer solid "pavement". No sieve-plate present. Parapores may be laterally interconnected. They may lead into irregular cavities or fistulose chamberlets between a paraporous wall-layer and the pavement. The partition between a main chamber lumen and a fistulose chamberlet, wherever present, is always paraporous. Compare: pores; pits.


See also


References

Hottinger (2006), Illustrated glossary of terms used in foraminiferal research. Carnets de Géologie, Memoir 2, ISSN 1634-0744.


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