Amphiraphia J.-Y.Chen & H.-Z.Zhu, 1983

Holotype species: Amphiraphia xizangensis J.-Y.Chen & H.-Z.Zhu

Original publication and holotype designation: Chen, J. & Zhu, H. (1983). Amphiraphisales, a new order of the pennatae, Bacillariophyta. Acta Phytotaxonomica Sinica 21(4): 449-457.

Description: Cells epiphytic, sometimes free-floating. Frustules in girdle view conspicuously arcuate with convex epitheca and concave hypotheca, heterovalvate. Valves naviculoid with rounded apices, symmetrical in valve view. The epivalve with a raphe composed of numerous slit-like openings, the central nodule more or less reduced and the polar nodules absent. The hypovalve with a straight, filiform raphe and well developed central and polar nodules. Two laminate chromatophores. Cells epiphytic, sometimes free-floating. Frustules in girdle view conspicuously arcuate with convex epitheca and concave hypotheca, heterovalvate. Valves naviculoid with rounded apices, symmetrical in valve view. The epivalve with a raphe composed of numerous slit-like openings, the central nodule more or less reduced and the polar nodules absent. The hypovalve with a straight, filiform raphe and well developed central and polar nodules. Two laminate chromatophores.

Information kindly contributed by M.C. Amspoker but may now be outdated.

Taxonomic status: This name is currently regarded as a synonym of Caloneis.

Most recent taxonomic treatment adopted: Mann, D.G. (1989). On auxospore formation in Caloneis and the nature of Amphiraphia (Bacillariophyta). Plant Systematics and Evolution 163: 43-52.

Comments: The unique structure of the raphe on the epivalve separates Amphiraphia from other genera. Chen and Zhu (1983b) erected a new order, Amphiraphidales, to include Amphiraphia and Rhoicosphenia, genera having 2 valves dissimilar in rapheal type. Amphiraphia was collected from Tibet in marshes, rivers and ponds at altitudes in excess of 4100 m.

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Contributors
Some of the descriptions included in AlgaeBase were originally from the unpublished Encyclopedia of Algal Genera, organised in the 1990s by Dr Bruce Parker on behalf of the Phycological Society of America (PSA) and intended to be published in CD format. These AlgaeBase descriptions are now being continually updated, and each current contributor is identified above. The PSA and AlgaeBase warmly acknowledge the generosity of all past and present contributors and particularly the work of Dr Parker.

Descriptions of chrysophyte genera were subsequently published in J. Kristiansen & H.R. Preisig (eds.). 2001. Encyclopedia of Chrysophyte Genera. Bibliotheca Phycologica 110: 1-260.

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Citing AlgaeBase
Cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 30 October 2016. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. https://www.algaebase.org; searched on 25 April 2024