Valve is shaped like a lance head (lanceolate) with beak-like ends (rostrate) and measures between 24 - 35 µm in length and 6 - 7 µm in width.
Raphid diatom: raphe (middle line) is straight and the striae (row of areolae) are transapical with 20 striae in 10 µm.
Benthic species found on exposed rocky shores.
* Information compiled by Mr Pumlile Cotiyane
References
Giffen, M. H. 1975 An account of the littoral diatoms from Langeban, Saldanha Bay Cape Province, South Africa.18:71-95
Kociolek, J. P.; Balasubramanian, K.; Blanco, S.; Coste, M.; Ector, L.; et al. 2019 DiatomBase. Achnanthes yaquinensis McIntire & Reimer, 1974. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=621484 on 2019-03-12