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Rexlowea navicularis

Kociolek and Thomas 2010      Category: Symmetrical biraphid
BASIONYM: Navicula semen Ehrenb. 1841
SYNONYM(S): Placoneis navicularis  (Ehrenb.) E.J.Cox 2003 

Reimeria uniseriata


Rhoicosphenia abbreviata

LM scalebar = 10 µm = 40 pixels.


Contributor: Pat Kociolek - March 2011
Length Range: 44-132 µm
Width Range: 18–30 µm
Striae in 10 µm: 5–6 in the center, 20 at the apices


Valves are broadly lanceolate, with apices protracted to broadly rounded. The axial area is narrow and straight, forming a narrow, linear to ovoid central area. The raphe is lateral and undulate, with large, rounded external proximal ends and hooked external distal ends. Striae are radiate, with the 1st or 2nd stria at each apex parallel or, rarely, convergent. Within a stria, the marginal areola are large and coarsely arranged. The middle portion has areola comparatively smaller and rounded, and the areolae near the axial area form two rows per stria. The central area has large, round, isolated puncta. The smallest striae at the apices are multiseriate throughout their length.

Original Description

Basionym: Navicula semen
Author: Ehrenb. 1841
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Kociolek, P. (2011). Rexlowea navicularis . In Diatoms of the United States. Retrieved May 23, 2018, from

Species: Rexlowea navicularis

Contributor: Pat Kociolek

Reviewer: Sam Rushforth


Kociolek, J.P. and Thomas, E.W. (2010). Taxonomy and ultrastructure of five naviculoid diatoms (class Bacillariophyceae) from the Rocky Mountains of Colorado (USA), with the description of a new genus and four new species. Nova Hedwigia 90:195-214. 10.1127/0029-5035/2010/0090-0195

Krammer, K. and Lange-Bertalot, H. (1986). Bacillariophyceae. 1. Teil: Naviculaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Süsswasserflora von Mitteleuropa, Band 2/1. Gustav Fisher Verlag, Jena. 876 pp.

Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Rexlowea navicularis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 93028

Autecology Discussion