Spaulding, S.,
Edlund, M.
(2008).
Platessa.
In Diatoms of North America.
Retrieved September 07, 2024, from https://diatoms.org/genera/platessa
Monoraphid
Platessa
Frustules heterovalvar - one valve with a raphe, the other lacking a raphe
Valves nearly flat
Valves elliptic, linear-elliptic to elliptic-lanceolate
Striae mostly biseriate, sometimes uniseriate on raphe valve
Terminal raphe fissures absent
Frustules are heterovalvar, one valve possesses a raphe and the other valve lacks a raphe. Valves are elliptic, linear-elliptic or elliptic-lanceolate. Both of the valve faces are nearly flat, in contrast to other monoraphids that have convex and concave valve faces. Striae are mostly biseriate, but in some species the raphe valve face...