Simonsen 1974      Category: Symmetrical biraphid
TYPE SPECIES: Haslea ostrearia (Gaillon) Simonsen




Image Credit: Loren Bahls

CLASS: Bacillariophyceae
  ORDER: Naviculales
    FAMILY: Naviculaceae

  1. Valves lanceolate with acute apices
  2. Central costae thickened, forming a stauros-like structure
  3. Raphe sternum with asymmetric thickened area in the central valve
  4. Striae crossed by longitudinal strips

Valves are lanceolate with acute apices and a central raphe system. Two or three thickened transapical costae on either side of the valve center form a stauros-like structure. The raphe sternum is thickened on one side of the axial area and is fused to the central ribs, giving valves a cruciform appearance. Striae are uniseriate, containing rectangular or square poroids, and overlain externally by fine longitudinal strips, many of which may be continuous from pole to pole.

Haslea is primarily an epipelic and planktonic genus of marine habitats, but contains at least one species found in brackish inland waters: Haslea spicula (Hickie) Lange-Bertalot.

Cite This Page:
Bahls, L. (2012). Haslea. In Diatoms of the United States. Retrieved April 24, 2018, from http://westerndiatoms.colorado.edu/taxa/genus/haslea

Contributor: Loren Bahls - April 2012