The correct name for Pleurotaenium breve var. engleri (Desmidiaceae, Chlorophyta)

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Short Communication The correct name for Pleurotaenium breve var. engleri (Desmidiaceae, Chlorophyta) M. Isabella Claassen H .G.W.J. Schweickerdt Herbarium, Department of Botany, University of Pretoria, Pretoria, 0002 Republic of South Africa Accepted 15 March 1985

The correct name for Pleurotaenium breve Raciborski var. engleri (Schmidle) W. Krieger is P. raciborskii Croasdale var. engleri (Schmidle) Claassen. Die korrekte naam vir Pleurotaenium breve Raciborski var. engleri (Schmidle) W. Krieger is P. raciborskii Croasdale var. engleri (Schmidle) Claassen.

Keywords: Chlorophyta, Desmidiaceae, Pleurotaenium

Croasdale in Prescott et a/. (1975, p. 128) pointed out that Pleurotaenium breve Raciborski in Flora 81: 32, Plate 3, Figure 4 (1895) is an illegitimate homonym antedated by P. breve Wood in Proc. Acad. nat. Sci. Philadelphia 1868: 18 (1870) and Smithson. Contr. Knowledge 241, 19: 119, Plate 21, Figure 2 (1872). She proposed the new name P. raciborskii for Raciborski's species.

S.-Afr. Tydskr. Plantk., 1985, 51(4)

The correct name for the variety, therefore, is:

Pleurotaenium raciborskii Croasdale 1975, in Prescott, Croasdale & Vinyard 1975, A synopsis of North American desmids 2(1): 128 var. engleri (Schrnidle) Claassen comb. nov. Basionym: P. engleri Schmidle 1898, Bot. Jb. 26: 23, Plate I, Figure 16; P. breve Raciborski var. engleri (Schmidle) W . Krieger 1937, Rabenhorst's Kryptogamen-Flora 13 (1 / 1): 410, Plate 44, Figure 3 non P. breve Wood 1870, Proc. Acad. nat. Sci. Philadelphia 1868: 18.

Lectotype: Schmidle's Figure 16 on Plate 1 in Bot. Jb. 26 (1898). P. raciborskii var. engleri is extremely rare. To the best of my knowledge samples containing specimens of this taxon have been collected at only three localities on the African continent (See Schmidle 1898; Krieger 1937; Lind 1971; Claassen 1976).

References CLAASSEN, M. ISABELLA. 1976. Freshwater algae of southern Africa. 3. Pleurotaenium breve Raciborski var. engleri (Schmidle) Krieger and Penium gonatozygifonne Claassen sp. nov. from Transvaal. J/ S. Afr. Bot. 42(4): 377 - 382. KRIEGER, W. 1937. Die Desmidiaceen Europas mit Beri.icksichtigung der aussereuropaischen Arten. In: Kryptogamen-Flora von Deutschland, bsterreich und der Schweiz, ed. Rabenhorst, L. 13 (1 / 1): 377 - 712. Reprinted 1971 , Johnson Reprint Corporation, New York . LIND, EDNA M. 1971. Some desmids from Uganda. Nova Hedwigia 22: 535-585. PRESCOTT, G.W., CROASDALE, HANNAH T. & VINYARD, W.C. 1975. A synopsis of North American desmids. 2. Desmidiaceae: Placodermae I: I - 275 . University of Nebraska Press, Lincoln. SCHMIDLE, W. 1898. Die von Professor Dr Volkens und Dr Stuhlmann in Ost-Afrika gesammelten Desmidiaceen, bearbeitet unter Beni.itzung der Vorarbeiten von Prof. G. Hieronymus. Bot. Jb. 26: I -59.