Navicymbula pusilla
(Grunow in A. Schmidt) Krammer 2003 Category: Asymmetrical biraphid
BASIONYM: Cymbella pusilla Grunow in Schmidt et al. 1875
SYNONYM(S): Navicella pusilla (Grunow) Krammer | Seminavis pusilla (Grunow) Cox and Reid
LM scalebar = 10 µm = 80 pixels.
Observations
Contributor: Marina Potapova - November 2011
Length Range: 16-33 µm
Width Range: 4.2-5.9 µm
Striae in 10 µm: 16-18 in the center valve, 19-20 at the ends
Description
Valves are moderately dorsiventral with an arched dorsal margin and flat, or slightly convex, ventral margin. The apices are not protracted. The axial area is narrow and widens in the valve center to form a small, lanceolate central area. The raphe is straight and weakly lateral, with external proximal ends and terminal fissures hooked to the dorsal side. Striae are radiate in the valve center, becoming convergent at the ends. Areolae are apically elongated and number 45-55 in 10 μm.
Original Description
Basionym: Cymbella pusilla
Author: Grunow in Schmidt et al. 1875
Length Range: µm
Striae in 10 µm:
Original Description
Original Images
Cite This Page:
Potapova, M. (2011). Navicymbula pusilla. In Diatoms of the United States. Retrieved May 23, 2013, from http://westerndiatoms.colorado.edu/taxa/species/navicymbula_pusilla
Species: Navicymbula pusilla
Contributor: Marina Potapova
Reviewer: Sarah Spaulding
Image Credit: Marina Potapova
- Valves dorsiventral
- Valves 4.2-5.9 μm wide
- Central area small, lanceolate
- Terminal raphe fissures turned to dorsal side
- External proximal raphe ends turned to dorsal side
Valves are moderately dorsiventral, with arched dorsal margin and flat, or slightly convex, ventral margin. The axial area is narrow; it widens in the valve center to form a small lanceolate central area. The raphe is straight and weakly lateral, with external proximal ends and terminal fissures hooked to the dorsal side. Striae are radiate in the valve center, becoming convergent at the ends.
Compare
Navicymbula pusilla can be distinguished from other diatoms with dorsiventral valves by its straight raphe with both terminal fissures and external proximal ends turned to dorsal side.
Citations
Cox, E.J. and Reid, G. (2004). Generic relationships within the Naviculineae: a preliminary cladistic analysis. M. Poulin (ed.), Proceedings of the Seventeenth International Diatom Symposium, Ottawa, Canada, 25th-31st August 2002. Biopress Limited, Bristol, U.K. pp. 49-62.
Krammer, K. (1997). Die cymbelloiden Diatomeen. Eine Monographie der weltweit bekannten Taxa. Teil 1. Allgemeines und Encyonema. Bibliotheca Diatomologica 36: 1-382.
Krammer, K. (2003). Cymbopleura, Delicata, Navicymbula, Gomphocymbellopsis, Afrocymbella. Diatoms of Europe. Diatoms of the European Inland Waters and Comparable Habitats 4: 1-530.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: 47309
Autecology Discussion
Navicymbula pusilla is found in waters of high mineral content.