Karayevia nitidiformis

(Lange-Bertalot) Bukhtiyarova 2006      Category: Monoraphid
BASIONYM: Achnanthes nitidiformis Lange-Bertalot in Lange-Bertalot & Krammer 1989

Karayevia laterostrata

 

Karayevia oblongella

LM scalebar = 10 µm = 80 pixels.



Observations

Contributor: Megan Otu | Sarah Spaulding - March 2011
Length Range: 13.0-14.7 µm
Width Range: 4.2-4.3 µm
Striae in 10 µm: 19 on raphe valve, 19-21 on rapheless valve

Description

Valves are linear-elliptical with capitate apices. Axial area on raphe valve narrowly lanceolate; axial area on rapheless valve linear. Both valves lack a distinct central area. The raphe is straight. Striae on raphe valve are slightly radiate to parallel; each stria in the middle of the raphe valve consists of a transapically elongated areola. The striae on rapheless valve are slightly radiate to parallel; each stria consists of two transapically elongated areolae and the areolae are separated by a narrow longitudinal hyaline area on each side of the valve.

The specimens illustrated here (from high elevation lakes in Wyoming) represent the first verified record of K. nitidiformis in the US. These specimens have striae that are more parallel than the slightly radiate striae illustrated in the iconotype.



Original Description

Basionym: Achnanthes nitidiformis
Author: Lange-Bertalot in Lange-Bertalot & Krammer 1989
Length Range: 12-18 µm
Width Range: 4.5-5 µm
Striae in 10 µm: 21

Original Description

Valvae elliptico-lanceolatae apicibus protractis, capitatis, 12-18 μm longae, 4,5-5 μm latae. Raphovalva: Raphe recta filiformis, area axialis angustissima linearis, area centralis nulla. Striae transapicales radiantes, leviter in media parte et in finibus capitatis, magis sub apicibus, circiter 21/10 μm. Areovalva: Area axialis angustissima linearis sicut rapho-valva. Striae transapicales paulum aut modice radiantes, 21/10 μm, bilateraliter linea hyalina intermissae.

Schalen elliptisch-lanzettlich mit schmaler bis breiter vorgezogenen kopfigen Enden, Länge 12-18 μm, Breite 4,5-5 μm, R-Schale mit gerade verlaufenden, fadenförmigen Raphenästen und sehr enger, linearer Axialarea, Zentralarea fehlt. Str. in der Mitte schwächer, vor den kopfigen Enden stärker radial und polar wieder schwächer radial ver-laufend, um 21/10 μm. RL-Schale ebenfalls mit sehr enger, linearer Axialarea, Zentralarea fehlt. Str. schwach radial bis annähernd parallel, 21/10 μm, auf jeder Seite von einer feinen hyalinen Linie unterbrochen. Holotypus: Coll. Krasske 4795b (Fig. 74: 19-22) Fundort des Holotypus: Kilpisjärvi in Finnland, Grundschlamm

Vorkommen: mehrere Exemplare in verschiedenen Proben am Typen-habitat, ein weiteres Exemplar auf den Färöer-Inseln gefunden, eine weitere (fragliche) RL-Schale in einem Süβwasseraquarium. Das Wasser an den Fundorten ist aufgrund der Diatomeenflora als mäβig elektrolyt-arm, oligotroph, circumneutral zu charakterisieren.

Die Sippe zeigt Konvergenzen zu A. amoena (incl. der synonymisierten Sippen, insbesondere A. orientalis Hustedt), zur fragwürdigen A. nitida Cleve-Euler (siehe dort) und — was die Strukturen, nicht den Umriβ betrifft — auch A. suchlandtii. Ihre Merkmalskombination ist jedoch anders.

Original Images


Cite This Page:
Otu, M., and Spaulding, S. (2011). Karayevia nitidiformis. In Diatoms of the United States. Retrieved December 19, 2014, from http://westerndiatoms.colorado.edu/taxa/species/karayevia_nitidiformis

Species: Karayevia nitidiformis

Contributor: Megan Otu | Sarah Spaulding

Reviewer: Rex Lowe

Citations

Bukhtiyarova, L.N. (2006). Additional data on the diatom genus Karayevia and a proposal to reject the genus Kolbesia. Nova Hedwigia Beiheft 130: 85-96.

Lange-Bertalot, H. and Krammer, K. (1989). Achnanthes eine Monographie der Gattung mit Definition der Gattung Cocconeis and Nachtragen zu den Naviculaceae. Bibliotheca Diatomologica 18, 393 pp. Cramer, Berlin, Stuttgart.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Karayevia nitidiformis CAS

North American Diatom Ecological Database (NADED)

NADED ID: 125012

Autecology Discussion

To date, K. nitidiformis has been verified from Holly Lake, Grand Teton National Park, Wyoming. Several records at ANSP have been misidentified as K. nitidiformis, rather than K. amoena.

Images

Holly Lake, Grand Teton National Park

Credit/Source: S. Spaulding