Superfamily Ammodiscacea

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Superfamily Ammodiscacea

• It range from Early Cambrian to Recent times.
• All would be considered smaller benthic
  foraminifera although Astrorhiza can be up to 10
  mm in diameter.
• Saccammina (Silurian-Recent) is a simple globular
  form with a terminal aperture. Irregularly
  arranged chambers of similar type are found in
  the multilocular Sorosphaera (Silurian-Recent).
• In Technitella (Oligocene-Recent), the test is
  fusiform and built of selected sponge specules.
• Tubular tests have several apertures and may be
  simple and unbranched as in Bathysiphon
  (Cambrian, Ordovician-Recent), branched as in
  Rhyzammina (Recent) or radiating from a central
  point as in Astrorhiza (M. Ordovician-Recent).
• Planispiral coiling is seen in Ammodiscus
  (Silurian-Recent) and glomospiral coiling (like a
  skein of wool) in Usbekistania (Jurassic-Recent).

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Superfamily Lituolacea

• Tests of the Lituolacea are more complex than
  those of the Ammodiscacea.
• The simplest of the smaller benthic forms are
  commonly straight uniserial (e.g. Reophax) or
  biserial (Textularia).
• Traiserial tests are also common in the group
  (Verneuilina) and Miliammina is coiled like a
  miliolid.
• Coiled growth plans are also common, as in the
  planispiral Cyclammina and the trochospiral
  Trochammina.
• A combination of planispiral and uniserial growth
  is seen in the uncoiled test of Ammobaculites
• The larger agglutinated foraminifera have tests
  mostly constructed of calcareous particles with a
  mineral cement.
• Examples in the Lituolidae are found in rocks
  formed in warm shallow facies of Jurassic and
  Cretaceous age.
• Spirocyclina and its relatives had almost
  planispiral, compressed tests and labyrinthic
  walls.
• Loftusina resembles the more ancient fusulines in
  having planispiral fusiform test with a
  labyrinthic wall, irregular septa and chamberlets.

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