05 | 13

Gyrosigma attenuatum (Kützing) Rabenhorst

Classification:
Empire Eukaryota
Kingdom Chromista
Phylum Ochrophyta
Class Bacillariophyceae
Subclass Bacillariophycidae
Superorder Bacillarianae
Order Naviculales
Family Pleurosigmataceae
Genus Gyrosigma

Pictures

click on thumbnail for larger version.

Central raphe fissures.. 18 Jul 2011. F.A.S. Sterrenburg. © F.A.S. Sterrenburg (fass@wxs.nl).

SEM. F.A.S. Sterrenburg. © F.A.S. Sterrenburg.

LM. F.A.S. Sterrenburg. © F.A.S. Sterrenburg.

SEM. F.A.S. Sterrenburg. © F.A.S. Sterrenburg.

Gyrosigma attenuatum (Kützing) Rabenhorst SEM

Publication details
Gyrosigma attenuatum (Kützing) Rabenhorst 1853: 47

Original publication: Rabenhorst, L. (1853). Die Süsswasser-Diatomaceen (Bacillarien.): für Freunde der Mikroskopie. pp. i-xii, 1-72. Leipzig: Eduard Kummer.
Download PDF

Type species
The type species (holotype) of the genus Gyrosigma is Gyrosigma hippocampus (Ehrenberg) Hassall.

Status of name
This name is of an entity that is currently accepted taxonomically.

Basionym
Frustulia attenuata Kützing

Origin of species name
Adjective (Latin), attenuate (Stearn 1973).

Homotypic Synonym(s)
Frustulia attenuata Kützing 1834
Sigmatella attenuata (Kützing) Brébisson & Godey 1835
Navicula attenuata (Kützing) Kützing 1844
Pleurosigma attenuatum (Kützing) W.Smith 1852
Scalptrum attenuatum (Kützing) Kuntze 1891
Gyrosigma attenuatum (Kützing) Cleve 1894

Heterotypic Synonym(s)
Gyrosigma attenuatum f. typica Rabenhorst
Navicula hippocampus Ehrenberg 1838
Gyrosigma hippocampus (Ehrenberg) Hassall 1845
Frustulia hippocampus (Ehrenberg) Jenner 1845
Pleurosigma hippocampus W.Smith 1852
Pleurosigma attenuatum var. hippocampus (Ehrenberg; W.Smith) H.Peragallo 1891
Gyrosigma attenuatum var. hippocampus (Ehrenberg; W.Smith) Schulz 1926

General environment
This is a freshwater species.

Description
Valve moderately sigmoid, narrowly lanceolate, gradually tapering to ±broadly rounded ends, 150-250 µm long, 22-26 µm wide. Raphe sternum with double curvature, becoming eccentric near the apex, raphe angle -2 to + 1°. Central raphe fissures only just projecting into the central area, variable in shape but always suddenly deflected and isomorphic (always deflected to the convexity of their raphe branch). Central area oval to more or less rhomboid, rotated. Terminal areas lateral, with an isolated lateral row of minute foramina, just visible in the LM, as a continuation of a row of coarse areolae that runs halfway around the apex. Striae transverse 14-16 in 10 µm, longitudinal clearly coarser, 10-12 in 10 µm.

Habitat
One of the most common, mainly benthic, Gyrosigma species in fresh and slightly brackish waters (including the Baltic), probably occurring worldwide, personally (Sterrenburg) observed throughout Europe, in the USA, South Africa and New Zealand.

Distribution by country

Detailed distribution with sources
(as Gyrosigma hippocampus (Ehrenberg) Hassall)
Europe: Britain (Whitton et al. 2003).

South America: Brazil (Eskinazi-Leça et al. 2010).

South-west Asia: Pakistan (Ghazala & Shakil 2010).

Australia and New Zealand: New Zealand (Harper et al. 2012).

(as Gyrosigma attenuatum (Kützing) Rabenhorst)
Europe: Poland (Zelazna-Wieczorek 2011).

North America: United States of America (Patrick & Reimer 1966).

(as Gyrosigma attenuatum (Kützing) Cleve)
Europe: Britain (Whitton et al. 2003), Romania (Caraus 2002, Caraus 2012), Spain (Álvarez Cobelas & Estévez García 1982, Aboal, Marín & Zafra 2003, Pérez, Maidana & Comas 2009), Turkey (Europe) (Ersanli & Gönülol 2006).

South America: Brazil (Eskinazi-Leça et al. 2010).

South-west Asia: Turkey (Asia) (Soylu & Gonulol 2006).

Australia and New Zealand: New South Wales (Day et al. 1995), New Zealand (Harper et al. 2012), Northern Territory (Day et al. 1995), Queensland (Day et al. 1995), Victoria (Day et al. 1995).

Nomenclatural notes
Ehrenberg arbitrarily renamed Kützing Frustulia attenuata as Navicula hippocampus (subsequently renamed Gyrosigma hippocampus by Rabenhorst), thus creating confusion that lasted for 150 years. However, the name Gyrosigma hippocampus remains the type of the genus, although it is illegitimate and may not be used for identification. - (5 Jul 2011) -

SAG Cultures
SAG Cultures may be viewed at http://sagdb.uni-goettingen.de/showstrains.php?genus=Gyrosigma&species=attenuatum

SCCAP Cultures
Cultures from the Scandinavian Culture Collection of Algae at the University of Copenhagen (SCCAP) and Protozoa may be viewed at http://www.sccap.dk/search/algaebase.asp?Genus=Gyrosigma&Species=attenuatum

NCBI Nucleotide Sequences

Created: 14 March 2009 by Salvador Valenzuela Miranda

Verified by: 06 July 2011 by M.D. Guiry

Accesses: This record has been accessed by users 842 times since it was created.

Linking to this page: http://www.algaebase.org/search/species/detail/?species_id=134445

Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 19 May 2013.

Algaebase taxon LSID: urn:lsid:algaebase.org:taxname:91868

Website Design : 249 Design Studio