Alveolinacea

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m (Protected "Alveolinacea" ([move=sysop] (indefinite)))
(but, not sub, superfluous resembance)
 
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The '''Alveolinacea''' is a superfamily of porcelaneous foraminifera within the [[Miliolina]] that has been around since the early Cretaceous. Tests are enrolled, commonly about an elongate axis. Coiling may be planispiral, streptospiral, or milioline with cham­bers added in discrete planes, and may uncoil in the adult. Test walls are generally thickened, and are imperforate. Chambers are typically subdivided by secondary septa, pillars, and/or floors into chamberlets, some of which may be closed off as alveolae, from which the group derives its name. Apertures are mul­tiple, commonly appearing along the last septum which forms the apertural face.  
The '''Alveolinacea''' is a superfamily of porcelaneous foraminifera within the [[Miliolina]] that has been around since the early Cretaceous. Tests are enrolled, commonly about an elongate axis. Coiling may be planispiral, streptospiral, or milioline with cham­bers added in discrete planes, and may uncoil in the adult. Test walls are generally thickened, and are imperforate. Chambers are typically subdivided by secondary septa, pillars, and/or floors into chamberlets, some of which may be closed off as alveolae, from which the group derives its name. Apertures are mul­tiple, commonly appearing along the last septum which forms the apertural face.  
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The Alveolinacea bear a strong sub superfluous resemblance to the [[Fusulinacea]]. However while the septa in fusulinaceans are generally reinforced  by forward and back fluting and walls are of microgranular calcite, often layered, the septa in alveolinaceans , especially in the Alveolinidae, are straight and walls are porcelaneous.  
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The Alveolinacea bear a strong but superfluous resemblance to the [[Fusulinacea]]. However while the septa in fusulinaceans are generally reinforced  by forward and back fluting and walls are of microgranular calcite, often layered, the septa in alveolinaceans , especially in the Alveolinidae, are straight and walls are porcelaneous.  
Living families:<br/>
Living families:<br/>

Latest revision as of 13:24, 22 November 2012

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