Saprolegnia - The iLumina Digital Library

Among the species of Saprolegnia with eccentric oospores, S. eccentrica is easily
recognized because it lacks antheridial branches (Figs. 101 A-C). Its chief characteristics
are shared with S. richteri, save for the presence of antheridia in the latter. We have not
seen specimens of S. richteri, but should the presence or absence of antheridial branches
prove to be variable, S. richteri properly would be merged with S. eccentrica. Like S.
eccentrica, S. luxurians has predominantly one oospore in the oogonium; the latter has
larger oospores (and oogonia) than the former, and possesses a well-developed
antheridial apparatus.
Dick (1960c: fig. 3 H-K) figures subeccentric oospores for Isoachlya (=Saprolegnia)
eccentrica. None of the oospores in the specimens of S. eccentrica that we have examined
possessed such a refractive body disposition pattern, and certainly Coker (loc. cit.) had
described and illustrated the oospores of I. eccentrica as eccentric. It is possible that Dick
had at hand another species. Although V. D. Matthews (1935) reported seeing
internally proliferated sporangia (saprolegnoid renewal), in specimens of I. eccentrica,
Coker (loc. cit.) had earlier stated that his species never displayed such a pattern.
CONFIRMED RECORDS: -- BRITISH ISLES: O’Sullivan (1965:301, fig. II-36-48).
CANADA: Maestres (1977:146). CZECHOSLOVAKIA: Cejp (1959a:198, fig. 70).
POLAND: Staniak (1971:362). UNITED STATES: Coker (loc. cit.); V. D. Matthews
(1935:307); Seymour (loc. cit.). USSR: Morochkovs’kiĭ et al. (1967:132, fig. 117).
RECORDED COLLECTIONS: -- BRITISH ISLES: Cook and Morgan (1934); Dick
(1962, 1963); Dick and Newby (1961); Hunter (l975). CANADA: Maestres and Nolan
(1978). GERMANY: Höhnk (1935a). INDIA: J. N. Rai and Misra (1977b:76, fig. 3a).
JAPAN: Suzuki (1960c). UNITED STATES: R. L. Butler (1975: figs. 17-20); Coker (1927);
J. V. Harvey (1925a, b; 1927b, c; 1930); G. C. Hughes (1959, 1962); Klich (1980); V. D.
Matthews (1927); A. W. Ziegler (1958b).
SPECIMENS EXAMINED: -- SWEDEN (1), TWJ. UNITED STATES (14), RLS.
Centraalbureau (1).
Saprolegnia richteri Richter ex Seymour
Nova Hedwigia (Beiheft) 19:53. 1970
Isoachlya terrestris Richter, Flora 131:242, figs. 5, 6. 1937.
Cladolegnia terrestris (Richter) Johannes, Feddes Repert. Spec. Nov. Regni Veg., p. 216.
1955.
Monoecious. Hyphae delicate, sparingly branched. Sporangia cylindrical or
slightly irregular, or fusiform and tapering toward the apex; producing lateral,
cylindrical or fusiform branches; renewed internally or by sympodial branching; 293-
543 x 25-44 µm. Spores apparently dimorphic; discharge and behavior saprolegnoid;
primary() spore cysts 8-10 µm in diameter. Gemmae unknown. Oogonia lateral;
globose, seldom somewhat irregular; 32-44 µm in diameter. Oogonial wall unpitted;
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