(Agardh) Silva et al. 2013 Category: Asymmetrical biraphid
BASIONYM: Gloionema leibleinii Agardh 1830
REPORTED AS: Encyonema prostratum (Diatoms of the US)
Contributor: Elizabeth Alexson - June 2014
Length Range: 40-65 µm
Width Range: 16-23 µm
Striae in 10 µm: 7-10
Valves are semi-lanceolate and dorsiventral. The dorsal margin of valve is highly arched. The ventral margin of the valve is slightly convex. Valve apices are broadly rounded and becoming rostrate in larger valves and usually ventrally bent. The narrow, straight axial area runs the length of the valve. The central area is circular. The raphe is simple. Proximal raphe ends curve slightly to the dorsal margin. Distal raphe ends deflect ventrally and do not reach the valve margin. Striae are punctate. Dorsal striae are radiate throughout, while ventral striae radiate at the valve center and become parallel, or even convergent, near the valve apices. Areola density 16-20 in 10 µm.
Note that Patrick and Reimer (1975) report the maximum length of this taxon (as Cymbella proxima) as 80 µm.
Examination of type material (Silva et al. 2013) led to determination that the name E. leibleinii has priority over E. prostratum (Berkeley) Kützing, which was previously used on this page (see UPDATE tab).
Basionym: Gloionema leibleinii
Author: Agardh 1830
Length Range: µm
Striae in 10 µm:
filis abbreviatis, granulis uniseriatis fuscis
Cite This Page:
Alexson, E. (2014). Encyonema leibleinii. In Diatoms of the United States. Retrieved March 22, 2017, from http://westerndiatoms.colorado.edu/taxa/species/encyonema_leibleinii
Species: Encyonema leibleinii
Contributor: Elizabeth Alexson
Agardh, C. A. (1830). Conspectus Criticus Diatomacearum. Part 2. Lundae. Litteris Berlingianis. pp. 17-38.
Berkeley, M.J. (1833). Gleanings of British algae; being an appendix to the supplement to English Botany. C.E. Sowerby, London, 50 pp., 20 pls.
Kützing, F.T. (1844). Die kieselschaligen Bacillarien oder Diatomeen. Nordhausen. 152 pp., 30 pls.
Patrick, R.M. and Reimer, C.W. (1975). The Diatoms of the United States, exclusive of Alaska and Hawaii, V. 2. Monographs of the Academy of Natural Sciences of Philadelphia 13.
Round, F.E., Crawford, R.M. and Mann, D.G. (1990). The Diatoms. Biology and Morphology of the Genera. Cambridge University Press, Cambridge, 747 pp.
Silva, W.J., Jahn, R., Ludwig, T.A.V. and Menezes, M. (2013). Typification of seven species of Encyonema and characterization of Encyonema leibleinii comb. nov. Fottea, Olomouc 13(2): 119–132.
Colonies were found in a plankton tow of the wave zone in Silver Lake, Dickinson County, Iowa. Other specimens were found in episammon, epilithic, and dredge samples from West Lake Okoboji, Dickinson County, Iowa. The genus Encyonema is commonly colonial and grows in mucilage tubes that attach to substrate. They are found in many freshwater communities and are most common in lentic systems (Round et al., 1990).
Cells of growing within a mucilage tube, its typical growth habit. Cells of the blue-green alga Planktothrix surround the diatom colony.
Credit/Source: Kalina Manoylov
From 1 August 2014 to 14 March 2016, the specimens on this page were presented as Encyonema prostratum (Berkeley) Kützing 1844. Silva et al. (2013) examined the type material of a number of species of Encyonema and stated that E. prostratum, E. paradoxum and E. leibleinii are synonomous. The epithet of E. leibleinii, however, has priority and here becomes the name on this page. - S. Spaulding