Key To Species

la. Cell wall coarsely silicified, valve face between elevations evenly inflated 2

lb. Cell wall weakly silicified, middle part of valve face shaped in various ways 3

2a. Valve wall with shorter or longer spines, elevations robust, slightly divergent O. litigiosa16 (Van Heurck) Hoban in Hoban et al.

2b. Valve wall coarsely areolated with no spines, elevations obtuse, inflated at base, divergent O. aurita (Lyngbye) C. A. Agardh

3a. Processes at a fair distance from the elevations 4

3 b. Processes close to slender elevations, valve face between processes flat or concave O. sinensis16 (Greville) Grunow

4a. Elevations prominent, valve face flat or concave or bulging in the middle 5

4b. Elevations inconspicuous, often more than two processes, divergent in direction, valve face flat or evenly convex

O. weissflogii16 (Janisch) Grunow

5a. Processes close together on a narrow, bulging middle part of valve face, external tubes diverging, elevations in pervalvar direction

O. longicruris16 (Greville) Hoban

5 b. Middle part of valve face flat or slightly concave, external tubes of processes and elevations diverging O. mobiliensis16 (Bailey) Grunow

Distribution:

O. aurita—cosmopolitan?, "usually in long chains attached to a substratum" (Hendey, 1964).

O. litigiosa and O. weissflogii—southern cold water region.

O. longicruris—warm water region to temperate.

O. mobiliensis, O. sinensis, and O. regia—cosmopolitan? How to identify: The species may be identified in water mounts.

" Basionyms: Biddulphia litigiosa Van Heurck, Biddulphia sinensis Greville, Biddulphia weissflogii Janisch, Biddulphia longicruris Greville, Zygoceros (Denticella?) mobiliensis Bailey, respectively. Synonyms: Biddulphia mobiliensis (Bailey) Grunow in Van Heurck and Biddulphia striata Karsten ( = 0. weissflogii), respectively.

Remarks: Odontella regia (Schultze) Simonsen (basionym: Denticella regia

Schultze) is close to O. mobiliensis. The Antarctic species have resting spores or appear in various phases (Hoban et al., 1980).

Was this article helpful?

0 0

Post a comment