Master Key to Pollen Types
1. Grains single
2. Grains with apertures
3. Structure expanded consisting of depressions surrounded by tall in often complex geometric patterns, echinate sculpture on top of walls, some depressions with apertures in bottom
Fenestrate
3’ Structure more compact, apertures on surface of grain
4. Apertures elongated furrows, may also have internal pores
5. Furrows with internal pores or shorter furrows
6. Three apertures
Tricolporate
6’ More than three apertures
7. Some furrows without pores
Heterocolpate
7’ All furrows with pores
Stephanocolporate
5’ Furrows simple, without pores or transverse furrows
8. One aperture
9. Aperture fused into a Y-shaped
10. Aperture restricted to one hemisphere
10’ Aperture the fusion of three bands that are continuous across both hemispheres (Syncolpate)
Pedicularis canadensis?
9’ Aperture not branched, a single furrow on a usually elongate grain
11. Grain without a casing, evidence of columellae or exine stratification
Monocolpate
11’ Grain encased in a loose usually sculptured casing, wall of grain structureless and without columellae
8’ Two apertures
Dicolpate
8’’ Three apertures
Tricolpate
8’’’ More than three apertures
12. Furrows arranged around equator of grain
Stephanocolpate
12’ Furrows scattered around entire surface of the grain
Pericolpate
4’ Apertures round or oval (pores)
13. One pore
Monoporate
13’ Three pores
13’’ Four or more pores
14. Pores arranged around equator of grain
Stephanoporate
14’ Pores scattered around entire surface of the grain
2’ Grains without apertures
15. Grains with attached bladders, often with a different sculpture pattern than the body
15’ Grains without bladders
1’ Grains in clusters
16. Clusters of four grains
Tetrad
16’ Clusters of many more than four grains
Polyad
