Compare

Brachysira ocalanesis is more narrow than B. microcephala. Brachysira microcephala also differs from B. vitrea by its narrower valve and coarser striae. In SEM, B. microcephala valves have blunt papillae compared to the longer, pointed papillae of B. vitrea. Brachysira silvicola (from New Caledonia) has truncated apices, a broader hyaline region between the axial area ribs, and fewer striae than B. microcephala. Brachysira hofmanniae (from Europe) has undulating valve margins and truncate to capitate apices.

LM scalebar = 10 µm
Ansp 15991A 13 Na Brachysira microcephala LM5 Brachysira microcephala LM2 Brachysira microcephala LM1 Brachysira microcephala LM4 Brachysira microcephala LM3 Brachysira microcephala LM6
Length Range
17-30 µm
Width Range
3.5-7 µm
Striae in 10 µm
30-36

Brachysira ocalanensis

Shayler and Siver 2004

Brachysira ocalanensis LM1 Brachysira ocalanensis LM2 Brachysira ocalanensis LM3 Brachysira ocalanensis LM4 Brachysira ocalanensis LM5 Brachysira ocalanensis LM6 Brachysira ocalanensis LM7
Length Range
19.0-38.6 µm
Width Range
4.0-5.7 µm
Striae in 10 µm
32-34, more closely spaced towards the apices

Brachysira vitrea

(Grunow) R.Ross in B.Hartley 1986

Brachysira Vitrea 1 Brachysira Vitrea 2 Brachysira Vitrea 3 Brachysira Vitrea 4 Brachysira Vitrea 5 Brachysira Vitrea 6 Brachysira Vitrea 7
Length Range
12.4-25.4 µm
Width Range
4.3-5.9 µm
Striae in 10 µm
32-36

Also compare to

Brachysira silvicola

Lange-Bert. in Lange-Bert. and Gerd Moser

Brachysira hofmanniae

Lange-Bert. in Lange-Bert. and Gerd Moser