Spaulding, S.,
Edlund, M.
(2008).
Achnanthes.
In Diatoms of North America.
Retrieved May 01, 2026, from https://diatoms.org/genera/achnanthes?x-craft-preview=409442409a997390693ff24c7010fd6f1c96fb56f8f091fa016a63de9a54aaccecpiqubknd
Monoraphid
Achnanthes
Frustules heterovalvar - one valve with a raphe, the other lacking a raphe
Raphe valve usually possesses a fascia
Valves shallow and arched in girdle view
Rapheless valve with a narrow, excentric sternum
The frustules of Achnanthes are heterovalvar. The raphe valve usually possesses a central area of thickened silica, called a fascia. The rapheless valve has no such central area and the sternum may be positioned near the valve margin. In girdle view, the mantle of the rapheless valve appears to be more ornamented than that of the raphe...