The main error sources comparison
between similes pollen
In some pollens the nexine and the sexine become separated from one another in the
vicinity of the pores: the cavity so formed is called “vestibulum”; if the sexine is thickened
markedly around the pores, an “aspis” forms Vestibulum (pl. vestibula) (Potonié, 1934)
Betula
Vestibulum
Aspis
When the intine swells beneath the pores it forms the “onci”
Corylus
Oncus
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Handbook for laboratory technicians
Pollen without apertures: inaperturate
Populus
A sudden thinning of the sexine around a colpus (yellow arrows).
Fraxinus
The lumina of the reticulum become smaller towards the colpus edge and disappear at the
edge;
The sexine becomes gradually thinner towards the colpus edge (Salix).
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Handbook for laboratory technicians
Acer - Quercus
SIZE
20-30
Quercus
23-28
Acer negundo
Acer campestre 28-35
APERTURES
3 colpi
3 colpi
3 colpi
CAR. COLPI
Large short
Large long
Large long
EXINE
Scabrate
Regulate
Striate
SEASON
4-6
3-5
4-5
Ambrosia, Artemisia, Xanthium
SIZE
Ambrosia 18-20
Artemisia 21-23
Xanthium 21-24
APERTURES
3 colporate
3 colporate
3 colporate
ECHINE
Long
short
short
EXINE
Circul/polig
Circul/lobate
circulare
SEASON
7-9
7-10
6-10
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Handbook for laboratory technicians
Morus, Parietaria, Cannabis
SIZE
Morus
16-20
Parietaria 13-25
Cannabis 21-24
PORES
2-3 (4)
3 (4-5)
3 (4)
TYPE
Large long
Small, operculos
annulus
ONCI
Convex
Small convex
large
SEASON
4-5
7-10
6-10
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Handbook for laboratory technicians
Fraxinus, Salix, Sambucus, Platanus
Fraxinus
Salix
Sambucus
Platanus
SIZE
18-27
16-24
16-20
18-25
APERTURES
3 (4) colpi
3 colpi
3 colpi
3 colpi
CAR. COLPI
Sharp longe
Large longe
Large longe
Granulate
LUMINA
Sharp
Large margo
Reticulate
reticulate
SEASON
2-3
3-4
4-5
4-5
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Handbook for laboratory technicians
Casuarina, Betula, Corylus, Carpinus, Ostrya
SIZE
Casuarina 28-32
18-25
Betula
20-28
Corylus
Carpinus 30-353
20-25
Ostrya
PORES
3
3 (4)
3
(3) 4 (5)
3 (4)
TYPE
Aspidate
Vest aspidate
Large
Little aspidate
Little aspidate
ONCI
Large flat
Small convex
Large convex
Large convex
Large convex
SEASON
11-2
3-5
12-3
3-5
3-5
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Handbook for laboratory technicians