Glossary of terms

In this glossary, you find explanations of the descriptive terms used. The terms are sorted by subject (e.g., you will find the term 'trochospiral' in the subject 'chamber arrangement'). You can use the links below to jump to a specific subject.

apertural structures, chamber shape, chamber arrangement, coiling, distribution,

primary aperture, pores, secondary aperture, size, spines, test margin, test outline,

texture, water depth, whole chambers in last whorl

apertural structures	lip	elevated border of aperture, may be small and at one side of aperture or completely surround it.
	rim	imperforated thickening around the margin of the aperture.
	flap	extension of last chamber that partly or fully covers the aperture.
	bulla	blister-like structure that partially or completely covers apertures; may have one or more accessory apertures; often has different texture than test surface.
	tooth	projection in aperture of test, may be simple or complex.
	toothplate	internal, apertural modification commonly consisting of contorted plate that extends from aperture through chamber to previous aperture.
chamber shape	spherical	round, sphere-like chambers.
	angular	mostly triangular or tetrahedric, edgy chambers.
	rounded	round, but not really spherical, may be pillow-like or hemispherical.
	elongate	radially elongated chambers, may have flask, bottle or ampullate form.
chamber arrangement	trochospiral	spirally coiled chambers, evolute on one side of test (spiral side), more involute on opposite side (umbilical side).
	planispiral	coiled in a single plain.
	spherical	round, sphere-like.
	streptospiral	coiled like ball of twine in all directions.
	triserial	chambers arranged in three columns, high trochospiral with three chambers in each whorl.
	biserial	having chambers arranged in two rows.
coiling	left	trochospiral coiling direction to the left (umbilical view).
	right	trochospiral coiling direction to the right (umbilical view).
distribution	Climatic region, where this species is predominantly found. Ranges from polar to tropical. Also restriction of some species to the Pacific or Atlantic Ocean.
primary aperture	umbilical	aperture positioned around the umbilicus.
	extraumbilical	aperture located sutural midway between umbilicus and periphery.
	interiomarginal	aperture at margin of final chamber, along final suture.
	equatorial	broad interiomarginal, from one side of the test to the other.
	sutural	located along sutures of chambers.
pores	although the pore size may change with environmental conditions, the general pore size is characteristic for some species. Microperforate species have pores that are not visible under conventional light microscopes.
secondary apertures	one	one additional opening into chamber cavity, commonly located on spiral side of specimen.
	two	two additional opening into chamber cavity, commonly located on spiral side of specimen.
	multiple	multiple additional openings into chamber cavity.
size	give minimum size, e.g., sieve size (63 or 150 µm).
spines	spines are fine elongate solid projections on the surface of the test. Each spine commonly comprises a single calcite crystal. Spines are usually not preserved in fossil specimens, as they are very fragile. In addition, the spines are lost during reproduction.
test margin	rounded	having a rounded outline in side view, no keel.
	keeled	having an angular outline in side view, and a clearly developed, imperforate keel.
test outline	lobulate	having clearly incised sutures.
	compressed	having weakly incised sutures.
	spherical	round, sphere-like outline, sometimes consisting of only one spherical chamber.
	conical	high trochospiral chamber arrangement, resulting in conical outline.
	disc-shaped	often low trochospiral or planispiral chamber arrangement.
	lanceolate	often associated with biserial or triserial or highly trochospirally arranged chambers.
texture of test surface	coarse	rough test surface, showing pits, spine bases, and/or pustules.
	hispid	covered with fine short spines or pustules.
	smooth	plain, sometimes shiny test surface.
	crystalline	some species develop a coarsely crystalline test surface during a late stage of their ontogeny.
water depth	water depth, where living specimens of this species usually dwell.
whole chambers in last whorl	give minimum number; do not count half chambers.