Holotype species: Anaulus scalaris Ehrenberg
Original publication and holotype designation: Ehrenberg, C.G. (1844). Einige vorläufige Resultate seiner Untersuchungen der ihm von der Südpolreise des Captain Ross, so wie von den Herren Schayer und Darwin zugekommenen Materialien über das Verhalten des kleinsten
Lebens in den Oceanen und den grössten bisher zugänglichen Tiefen des Weltmeeres. Bericht über die zur Bekanntmachung Geeigneten Verhandlungen Der Königl. Preuss. Akademie Der Wissenschaften zu Berlin 1844: 182-207.
Taxonomic status: currently recognized as a distinct genus.
Most recent taxonomic treatment adopted: Fourtanier, E.J. & Kociolek, J.P. (2009). Catalogue of diatom names: Part II: Abas through Bruniopsis. Occasional Papers of the California Academy of Sciences 156(II): 1-231, 2 figs, 1 table.
Description: There is doubt about the typification of this genus - A. scalaris is a large diatom and require re-investigation. Drebes & Schulz (1981) cultured and described a new species A. creticus and our description is based on material of that species kindly supplied by Dr. G. Drebes. The cells occur singly or in short chains attached at the poles and centres of the valve and leaving narrow spaces between the adjacent valve faces. Plastids single and lobed. Marine planktonic or perhaps associated with sediments. Valves narrowly ovoid in valve view (slightly indented at the pseudosepta) with two conspicuous pseudosepta crossing the valve. In girdle view cells oblong with short apical processes and a central rimoportula having an external tube of variable length. Valve surface areolate except in the regions of the pseudosepta. Areolae with delicate vela. Areolae are scattered on the valve face and in vertical rows on the mantle. The apical processes terminate in ocelli with no obvious porellar plate; Schulz et al. (1984) record fine granular material at the base of the ocellus in sections observed in TEM. The rimoportula is tubular both externally and internally (see Drebes & Schulz, 1981, figs 10 & 19). The pseudosepta are internal thickenings of the valve. The cingulum is composed of several (5-7) open areolate copulae.The most recent alteration to this page was made on 5 Apr 2015 by M.D. Guiry.
Comments: Until the type species and others are investigated (VanLandingham lists 19 spp.) it is not possible to comment in further detail. Drebes & Schulz consider that it is a heterogeneous group at the moment. Anaulus has been placed either in a family Anaulaceae (Hendey, 1964; Round & Crawford, 1988) or in the Biddulphiaceae (Simonsen, 1979).
Numbers of names and species: There are 32 species names in the database at present, as well as 4 infraspecific names. Of the species names, 9 have been flagged as accepted taxonomically on the basis of the listed literature under the species name. In some instances, opinions on taxonomic validity differ from author to author and users are encouraged to form their own opinion. AlgaeBase is a work in progress and should not be regarded as a definitive source only as a guide to the literature..
Names: ('C' indicates a name that is accepted taxonomically; 'S' a homotypic or heterotypic synonym; 'U' indicates a name of uncertain taxonomic status, but which has been subjected to some verification nomenclaturally; 'P' indicates a preliminary AlgaeBase entry that has not been subjected to any kind of verification. For more information on a species click on it to activate a link to the Species database):
Click here to also show infraspecific names in the list below.
Verification of data
Users are responsible for verifying the accuracy of information before use, as noted on the website Content page.
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.
Created: 23 April 2002 by M.D. Guiry
Verified by: 05 April 2015 by M.D. Guiry
Linking to this page: http://www.algaebase.org/search/genus/detail/?genus_id=44358
Please cite this record as:
M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2021. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 26 September 2021.