Compare

Eucocconeis laevis differs from Psammothidium rossii by having larger and often asymmetrical central areas on both valves and by wider valve ends. Psammothidium altaicum has rhomboid axial area on the rapheless valve and an elliptical symmetrical central area on raphe valve. In contrast to Eucocconeis spp., Psammothidium spp. have a convex raphe valve and concave pseudoraphe valve.

LM scalebar = 10 µm
Mo000019  Eulaev 1B Ed Gsn20110  Eulaevis 1A Ed Gsn23387  Eulaevis 1B Ed Gsn23387  Eulaevis 1A Ed Gsn20110  Eulaevis 3B Ed Gsn20110  Eulaevis 2A Ed Mo000019  Eulaev 1A Ed
Length Range
10-18 µm
Width Range
5.4-7.1 µm
Striae in 10 µm
25-35

Also compare to

Psammothidium altaicum

(V.S.Poretzky) Bukht. in Bukht. and Round

BioData Reference
Krammer and Lange-Bertalot 2/4 Pl 20 Fig 24-32

Psammothidium rossii

(Hust.) Bukht. and Round