Navicula cryptocephaloides

Hustedt 1937      Category: Symmetrical biraphid
BASIONYM: Navicula cryptocephaloides Hustedt 1937

REPORTED AS: Navicula ammophila (Witkowski, Lange-Bertalot, and Metzeltin 2000) 

Navicula cryptocephala

 

Navicula cryptofallax

LM scalebar = 10 µm = 40 pixels.



Observations

Contributor: Loren Bahls - November 2011
Length Range: 25-54 µm
Width Range: 7.3-9.7 µm
Striae in 10 µm: 13-14

Description

Valves are lanceolate with narrow, weakly protracted and acutely pointed to obtusely rounded apices. The axial area is narrow and the central area is small and irregularly rounded. The raphe is filiform. Proximal raphe ends are small, close together and nearly straight. Terminal raphe fissures are bent toward the secondary side of the valve. Striae are weakly radiate in the middle and become weakly convergent near the valve ends. Areolae are distinct and number about 24 in 10 µm.



Original Description

Basionym: Navicula cryptocephaloides
Author: Hustedt 1937
Length Range: 30-40 µm
Width Range: 7-9 µm
Striae in 10 µm: 14

Original Description

Schalen linear-lanzettlich mit wenig konvexen bis fast parallelen Seiten und leicht geschnabelten, nicht kopfigen Enden, 30-40 microns lang, 7-9 microns breit. Raphe gerade, Axialarea eng, Zentralarea quer verbreitert, unregelmassig begrenzt. Transapikalstreifen im mittleren Teil wenig radial, an den polen schwach konvergent, 14 in 10 microns, deutlich liniiert, Linien 28-30 in 10 microns. Taf. XVIII, Fig. 1, 2.

Original Images


Cite This Page:
Bahls, L. (2011). Navicula cryptocephaloides. In Diatoms of the United States. Retrieved April 23, 2014, from http://westerndiatoms.colorado.edu/taxa/species/navicula_cryptocephaloides

Species: Navicula cryptocephaloides

Contributor: Loren Bahls

Reviewer: Marina Potapova

Citations

Hustedt, F. (1937). Systematische und ökologische Untersuchungen über die Diatomeen-Flora von Java, Bali und Sumatra nach dem Material der Deutschen Limnologischen Sunda-Expedition. Archiv für Hydrobiologie, Supplement 15: 187-295.

Schmidt, A. (-). (1874-1959). Atlas der Diatomaceen-Kunde, von Adolf Schmidt, continued by Martin Schmidt, Friedrich Fricke, Heinrich Heiden, Otto Muller, Friedrich Hustedt. Reprint 1984, Koeltz Scientific Books, Konigstein, 480 plates.

Simonsen, R. (1987). Atlas and Catalogue of the Diatom Types of Friedrich Hustedt. J. Cramer, Berlin & Stuttgart 1: 525 pp.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Navicula cryptocephaloides CAS

North American Diatom Ecological Database (NADED)

NADED ID:

Autecology Discussion

There are 21 records of Navicula cryptocephaloides in the Montana Diatom Collection, all from streams in the Northwestern Great Plains Ecoregion of Montana, South Dakota, and Wyoming. Here it prefers warm, muddy, and brackish waters (mean conductivity = 18731 µS/cm). One of the MDC records is from Salt Creek, a small stream in northeastern Wyoming that is fed by salt springs. Here the conductivity measures 45700 µS/cm and chloride content is 13200 mg/L. Common diatom associates of Navicula cryptocephaloides in Salt Creek are Mastogloia pumila, Haslea spicula, and Nitzschia pararostrata. This taxon was described from salt springs in Java.

Images

Salt Creek, Weston County, Wyoming: home of Navicula cryptocephaloides.

Credit/Source: Photo courtesy Wyoming DEQ