Saprolegnia - The iLumina Digital Library

and tuberculate projections. Oogonial stalks ( 1 / 2 -) 1-1 1 / 2 (-3) times the diameter of the
oogonium in length; straight, branched, unbranched, or irregular. Oospores subcentric;
spherical or subspherical; 1-2 (-6) per oogonium and usually not filling it; (17-) 26-33
(-44) µm in diameter; germination not observed. Antheridial branches predominantly
androgynous, rarely monoclinous, very rarely diclinous; sometimes arising in a
clustered fashion below the oogonium; unbranched or branched, usually irregular in
general configuration; persisting. Antheridial cells simple; short-clavate or tuberous;
apically or laterally appressed; persisting; fertilization tubes present or absent, not
persisting.
The densely papillate oogonia that generally contain only one or two subcentric
oospores (Fig. 92 B, C, E) make this species easily identifiable. In gross culture,
specimens sometimes can be recognized by reason of the very diffuse, flaccid nature of
the mycelium.
Dick (1969a) placed this species in Scoliolegnia, a genus that we do not recognize.
An unusual “form” of Saprolegnia asterophora first described by Dick in 1960(c) later was
placed by him (1969a) in Scoliolegnia and renamed Scoliolegnia subeccentrica. We
recognize Dick’s species as a valid taxon of Saprolegnia.
Of the three taxa that Dick (1969a) considered to be an aggregate species --
Scoliolegnia (=Saprolegnia) asterophora, S. subeccentrica, and S. blelhamensis -- only S.
asterophora has subcentric oospores. With respect to the nature and density of its
oogonium wall ornamentations, S. asterophora (Fig. 92 B) very closely approaches S.
subeccentrica (Fig. 92 N, O).
CONFIRMED RECORDS: -- BRITISH ISLES: Dick (loc. cit.); Forbes
(1935b:7, fig. 2a-f). CANADA: Maestres (1977:150, figs. 46, 47). CZECHOSLOVAKIA:
Cejp (1959a:253,1 fig. 96) DENMARK: Petersen (1909a: fig. 3h; 1910: fig. 3h). FINLAND:
Häyrén (1927:50). GERMANY: de Bary (loc. cit.; 1881:269 et sqq., pl. 6, figs. 18-29;
1888:614); A. Fischer (1892: 343); Minden (1912:529, fig. 1h); Zopf (1890:297). ICELAND:
Howard et al. (1970: fig. 26). JAPAN: Kobayasi and Konno (1969:732, fig. 4 I-M);
Kobayashi and Ôkubo (1954:567, fig. 9); Shibuya (1959:148, fig. 3). LATVIA: Apinis
(1929a:218). MIDDLE EUROPE: Migula (1903:66). NETHERLANDS: Beverwijk
(1948:233, fig. 4). POLAND: Staniak (1971:366). REPUBLIC OF CHINA: Chiou and
Chang (1976:44, pl. 3, figs. 1-9). SWITZERLAND: Maurizio (1895d:13). UNITED
STATES: Beneke (1948b:46); R. L. Butler (1975: figs. 9-12); Coker (1923:64, pl. 19);
Humphrey (1893:110, pl. 17, figs. 54, 55); Seymour (1970:23, figs. 12-23). USSR:
Morochkovs’kiĭ et al. (1967:126, fig. 110); Naumov (1954:66). [Istvánffi (1895: pl. 35, figs.
19-21; pl. 36, fig. 22) studied this species cytologically, but gave no record of its source.]
RECORDED COLLECTIONS: -- BRITISH ISLES: Cook and Morgan (1934); Dick
(1962, 1963, 1964, 1966); Dick and Newby (1961); Perrott (1960); R. E. Roberts (1963);
Sparrow (1936). CANADA: Dick (1971c); Maestres and Nolan (1978). DENMARK: A.
Lund (1934, 1978). FINLAND: Häyrén (1956). GERMANY: Höhnk (1935a). JAPAN:
Shirai et al. (1927); Suzuki (1961f). UNITED STATES: Coker (1927); Klich (1980);
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