Glossary of Pollen Terminology
Amb – outline of a pollen grain seen in polar view. Usually, but not always, the same as equatorial outline.
Annulus – ring-like structure surrounding the pore, sharply differentiated from surrounding exine.
Aperture – opening or thin part of exine, usually associated with germinal apparatus.
Aperturate – with furrows, pores, or opening of some kind.
Apolar – grain without distinct polarity.
Aspidate - pores protruding.
Atectate – lacking a tectum. Used for primitive angiosperms lacking columellae.
Baculate –sculpturing containing rods or pillar-like processes, usually arising from the foot layer and often supporting the tectum.
Baculum – rod-like sculpturing element, with equal thickness throughout length.
Bilateral – pollen with a single plane of symmetry.
Bisaccate – pollen bearing two bladder-like sacci.
Bladders – the wing-like sacs in bisaccate pollen grains.
Circular – shape round in outline
Clavate – sculpturing elements with club-shaped swollen tips, thicker toward the apex.
Colpate – with at least one colpi, an elongated groove or furrow.
Colporate – aperture containing pores.
Colpus – elongated aperture shaped like a furrow, more than twice as long as broad.
Columellae – rod-like elements of the pollen wall extending from the foot layer to the tectum, supporting either a tectum or caput (expanded head of columella).
Costate – pollen with rib-like appearance of furrow edge.
Dicolpate – with two colpi, furrows.
Dimorphic – with two forms.
Diporate – with 2 pores.
Dyad – two pollen grains adhering together and dispersed as a unit.
Echinate – spiny sculpturing, with pointed processes > 1 μm high.
Elliptical – longer than wide.
Equator – plane halfway between proximal and distal poles, encircling the grain.
Eurypalynous – taxonomic group in which the pollen is variable between species.
Exine – the resistant outer wall of pollen grain.
Fenestrate – with large window-like opening (fenestrae) on the surface in a regular arrangement.
Foot layer – innermost layer of the outer pollen wall.
Fossulate – surface with grooved sculpturing pattern.
Foveolate – surface surface pitted, pits at least 1 μm in diameter.
Fusiform – spindle-shaped.
Fusiform - tapered at each end.
Gemmate – surface with bead-like sculpturing pattern, elements (gemmae) ball-shaped with constricted bases.
Heterocolpate – with two kinds of furrows on one pollen grain.
Heteropolar – poles dissimilar in shape, pattern, or arrangement of apertures.
Heteropolar – pollen asymmetrical, often with pores concentrated in one hemisphere.
Inaperturate – lacking apertures; no apparent furrows, pores or opening of any kind (or nearly so).
Isopolar – poles symmetrical, indistinguishable, with pores equally distributed in each hemisphere.
Lacunae – window-like opening in fenestrate pollen grain.
Lobate – with a lobed shape in polar view.
Lophate – surface with large window-like openings (lacunae), the tectum continuous across.
Monad – pollen grain appearing single.
Monocolpate – with one colpus, a single furrow.
Monoporate – surface with one pore.
Muri – wall-like raised portion of reticulate sculpturing.
Oblate – grain distinctly flattened at poles, wider at equator than at poles.
Octad – eight pollen grains adhering together and dispersed as a unit.
Operculate – aperture provided with lid covering aperture, separate from surrounding exine.
Ovate – longer than wide, broad at one base.
Pentacolpate – with five apertures.
Pericolpate – colpi distributed more or less evenly over surface of spheroidal grain..
Pericolporate – pollen with numerous furrows with pores.
Periporate - numerous pores distributed more or less evenly over spheroidal pollen grain.
Polar view – view in which the polar axis is directed towards the observer.
Pollenkitt – sticky material produced by the tapetum which may hold pollen together during dispersal.
Pollinium – waxy clump of pollen grains adhering together and dispersed as a unit.
Polyad – more than 8 pollen grains adhering together and dispersed as a unit.
Porate – with pore-like apertures in exine.
Prolate – pollen grain longer in polar axis than equatorial axis, longer than wide..
Psilate – surface smooth, with no visible features
Quadrangular - 4-angled.
Quinquangular - 5-angled.
Reticulate – surface with net-like sculpturing pattern, composed of muri enclosing lumina.
Rugulate – surface with irregularly distributed strips at least twice as long as broad.
Scabrate – surface with small isodiametric rough spots, less than 1 μm diameter.
Semi-tectate – partially tectate exine, tectum broken up in irregular pattern.
Size Classes – length of longest axis
Size Minute - <10 μm
Size Small - 10-25 μm
Size Medium - 25-50 μm
Size Large - 50-100 μm
Size Very large - 100-200 μm
Size Gigantic - >200 μm
Spheroidal – more or less spherical.
Spinulose – pattern composed of many spinules.
Stenopalynous – a group in which the pollen is very similar among species.
Stephanocolpate – with four or more furrows centered on equator.
Stephanocolporate – pollen with four or more equatorial furrows, each with a pore.
Stephanoporate – pollen with four or more equatorial pores.
Striate – surface with parallel ridges and striae (groove between ridges).
Sulcus – latitudinal elongated aperture, not orientated toward the poles.
Syncolpate – pollen grain with furrows extending to poles and fusing with other furrows, sometimes forming spiral, or circular pattern.
Tectate – exine with a tectum, an outermost layer often covered with sculpturing.
Tetrad – four pollen grains adhering together and dispersed as a unit.
Triangular - 3-angled.
Tricolpate – with three colpi, furrows.
Tricolporate – pollen with three furrows containing pores.
Triporate – with 3 pores.
Tuberculate – covered with knobby projections.
Verruculate – surface with wart-like pattern, covered with small non-constricted projections (verrucae).
Vesiculate – pollen with two bladders or wings.
Viscin threads – thread-like hairs attached to pollen, resistant to acetolysis, characteristic of Onagraceae.
Zonoaperturate – apertures situated only at equator.
Zonoporate – pores situated only at equator
