Diatoms of North AmericaDiatoms of North America
Return to overview

Compare Aulacoseira humilis

(A.Cleve) Genkal and Trifonova in Trifonova and Genkal 2001

Compare

Aulacoseira humilis is distinguished from Aulacoseira nivalis, A. nivaloides and A. tenella by its long, thin spines 3 µm long. The spines of the other species do not much exceed 1 µm in length. The striae of A. humilis also have a distinct appearance, because of double rows of fine areolae, which are almost unresolvable in LM. The striae are separated by prominent costae, giving valves a "striped" appearance, whereas the other species have distinct, larger areolae with no significant pervalvar costae between the rows of areolae. The concave/convex valve face of A. humilis distinguishes it from many other low-mantle Aulacoseira species except A. nivaloides, but this species has more closely space striae than A. humilis.

LM scalebar = 10 µm
Aulacoseira humilis LM6 Aulacoseira humilis LM4 Aulacoseira humilis LM5 Aulacoseira humilis LM1 Aulacoseira humilis LM2 Aulacoseira humilis LM7 Aulacoseira humilis LM3
Diameter
5-9 µm
Width Range
2-5 µm
Striae in 10 µm
24-40

Aulacoseira nivaloides

(Camburn) English and Potapova 2009

Aulacoseira nivaloides LM3 Aulacoseira nivaloides LM2 Aulacoseira nivaloides LM6 Aulacoseira nivaloides LM7 Aulacoseira nivaloides LM1 Aulacoseira nivaloides LM5 Aulacoseira nivaloides LM4
Diameter
4-11 µm
Width Range
4-7 µm
Striae in 10 µm
14-22

Aulacoseira tenella

(Nygaard) Simonsen 1979

Gsn97387 1B Gsn97387 1A Gsn97387 5A Gsn97387 3A Gsn97387 3B Gs024173 1A Gs024173 1B
Diameter
5-8.5 µm
Width Range
1.8-2.6 µm
Striae in 10 µm
21-25

Aulacoseira nivalis

(W.Sm.) English and Potapova 2009

Aulacoseira nivalis LM2 Aulacoseira nivalis LM1 Aulacoseira nivalis LM3 Aulacoseira nivalis LM6 Aulacoseira nivalis LM5 Aulacoseira nivalis LM4 Aulacoseira nivalis LM7
Diameter
6-18 µm
Width Range
2.5-6 µm
Striae in 10 µm
12-16