Anchispirocyclina

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Anchispirocyclina
Temporal range: Late Jurassic–Early Cretaceous
Anchispirocyclina henbesti.jpg
Anchispirocyclina henbesti
Scientific classification
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Anchispirocyclina

Jordan and Applin, 1952

Anchispirocyclina is a genus of agglutinated discoidal forams known from the upper Jurassic (lower Kimmeridgian) to the lower Cretaceous (lower Valanginan) of Europe, north Africa, USA (North Carolina) and Cuba.

The test of Anchispirocyclina is discoidal, thin and often slightly undulating. The early stage is close coiled, later flaring some becoming circular in outline. Walls are microgranular to finely agglutinated. Chambers have complex interiors produced by a network of rafters and beams. Those near the median plane have an irregular labyrinthic structure produced by radial pillars or buttresses extending from septum to septum between adjacent apertural openings.

Spirocyclina , Haurinia and Martiguesia are related genera.

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<span class="mw-page-title-main">Textulariida</span> Order of single-celled organisms

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<span class="mw-page-title-main">Lagenida</span> Order of single-celled organisms

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Spirocyclinidae is a family of foraminifera included in the order Loftusiida.

<span class="mw-page-title-main">Cyclamminidae</span> Family of single-celled organisms

Cyclamminidae is a family of Foraminifera in the order Loftusiida, ex textulariid subfamily Cyclammininae in the Treatise on Invertebrate Paleontology Part C, Protista 2.

Spirocyclina is a genus of large forams, with a flat test as much as 10mm in diameter. Coiling is planispiral to slightly asymmetric and mostly involute, some becoming uncoiled with a straight final stage. The final whorl, or stage, has about 25 strongly arcuate chambers. Composition is of agglutinated matter, the outer layer of the wall imperforate. Chambers are subdivided into secondary chamberlets by internal structures. The aperture consists of a double row of pores on the apertural face. Anchispirocyclina and Martiguesia are among related genera.

Haurania is a genus of elongated, finely agglutinated benthic foraminifera included in the Spirocyclinidae. The test is free, starting with a brief planispiral coil followed by a straight uncoiled stage. The exterior is imperforate, the interior divided by radial septula or beams, perpendicular to the septa and outer wall. The aperture is cribrate, a series of openings on the terminal face.

Martiguesia is a genus of agglutinated benthic forams from the Upper Cretaceous (Santonian) of France. The test is free, the early stage planispirally coiled, becoming nearly straight during later growth. The agglutinated wall is externally imperforate, the interior with a coarse alveolar network. Chambers are subdivided and almost completely filled by irregular radial pillars. The aperture, cribrate.

Pseudospirocyclina is a genus of large planispirally coiled agglutinated benthic forams with a complex interior known from the upper Jurassic (Kimmeridgian) of Portugal and Morocco.

Saudia is a genus of large discoidal to reniform forams, with a relatively thick test and complex interior, composed of agglutinated matter, or microgranular calcite. Saudia is known from the Paleocene to middle Eocene of Saudi Arabia, Iraq and the balkans. Related genera include Vania, Sornayina, and Haurania.

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