Tetracyclus hinziae

Bishop and Spaulding 2015      Category: Araphid

Tetracyclus glans


Tetracyclus rupestris

LM scalebar = 10 µm = 40 pixels.


Contributor: Ian Bishop - December 2014
Length Range: 8-36 µm
Width Range: 5.6-14.0 µm
Striae in 10 µm: 20-27


Valves are lanceolate-elliptical, with rounded to cuneate ends. Costae number 1-3 in 10 µm. Striae are radiate. Areolae may, or may not, be visible in LM on larger specimens. Costae are heavily silicified. Each girdle band contains a septum, which alternates between poles in adjacent copulae. A single transversely oriented rimoportula is located between the first and second costae toward one end, near the sternum. Copulae in girdle view are relatively linear and only slightly overlap.

Original Description

Author: Bishop and Spaulding 2015
Length Range: 8.2-35.5 µm
Width Range: 5.6-14.0 µm
Striae in 10 µm: 20-27

Original Description

Original Images

Cite This Page:
Bishop, I. (2014). Tetracyclus hinziae. In Diatoms of the United States. Retrieved April 25, 2018, from http://westerndiatoms.colorado.edu/taxa/species/tetracyclus_hinziae

Species: Tetracyclus hinziae

Contributor: Ian Bishop

Reviewer: Eduardo A. Morales


Bishop, I.W. and Spaulding, S.A. (2015). Tetracyclus hinziae (Bacillariophyta), a new species from the central Cascade Mountains (WA, USA). Phytotaxa 205(3): 197-204. 10.11646/phytotaxa.205.3.7

Williams, D.M. (1985). Morphology, taxonomy and inter-relationships of the ribbed araphid diatoms from the genera Diatoma and Meridion (Diatomaceae: Bacillariophyta). Bibliotheca Diatomologica 8: 1-228.

Williams, D.M. (1987). Observations on the genus Tetracyclus Ralfs (Bacillariophyta) I. Valve and girdle structure of the extant species. British Phycological Journal 22: 383-399. 10.1080/00071618700650451

Williams, D.M. (1989). Observations on the genus Tetracyclus Ralfs (Bacillariophyta) II. Morphology and taxonomy of some fossil species previously classified in Stylobium Ehrenberg. British Phycological Journal 24: 317-327.

Williams, D.M. and Li, J. (1990). Observations on the diatom genus Tetracyclus Ralfs (Bacillariophyta) III. Description of two new species from Chinese fossil deposits. British Phycological Journal 25: 335-338.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

North American Diatom Ecological Database (NADED)


Autecology Discussion

Tetracyclus hinziae has been documented in several catchments in the Cascade Mountain Range, from shaded 1st order streams such as Mason Creek and Van Trump Creek, to wider, unshaded 3rd order rivers such as the South Fork Snoqualmie River. Tetracyclus hinziae is abundant in mossy splash zones and co-occurs with common araphids, including T. glans, Tabellaria flocculosa, Meridion circulare and Diatoma mesodon. It is likely often misidentified as the last of these (Bishop and Spaulding 2015).


Living cells of T. hinziae showing multiple chloroplasts. Scale bar is equal to 20 µm.

Credit/Source: Sarah Spaulding

Mason Creek, Washington

Credit/Source: Ian Bishop