Phylum：Oomycota　>>　Class： Oomycetes　>>　 Order： Saprolegniales 
   
 
　BCRC Number： NO BCRC Number!  
   
　Scientific Name： Saprolegnia asterophora
 
   
   
　Author：

Saprolegnia asterophora deBary Jahrb. F. Wiss. Bot. 2:189, pl. 20, figs. 25-27, 1860.
   
 
 
 
 
　Description： Zoosporangia rare, secondary zoosporangia formed basipetally, not by internal proliferation. Gemmae abundant, irregular, sometimes becoming zoosporangia. Zoospore discharge saprolegnoid. Oogonial abundant, terminal or more frequently lateral on long or short branches, rarely intercalary; roughly spherical, often irregular or broadly lobed; papillation variable, nearly smooth to moderately or rarely densely covered with long papillae. Oogonia 25-66 μ indiameter, exclusive of papillae, predominantly 40-50μ. Antheridial rare, if any, androgynous.Oogonium containing 1-14 oospores, mostly 4-6. Oospores 15-35μ in diameter, predomintantly 20-27μ; centric, subcentric type Ⅰ or rarely subcentric type Ⅱ.
 
 
 
 
 
　Specimens：

Collected one from Taipei, Dec. 25, 1974.
 
 
 
　Habitat： Soil and water
 
 
 
　Distribution：

Anglia,UK ; BElgio ; German ; Taiwan
 
 
 
　References：

Seymour RL. 1970; Dick MW. 1969.
   
   
   
　Provided：

T. S. Chiou and H. S. Chang
 
 
　Note： Dick (1969a) used subeccentric to designate oospores with one or more layers of large oil droplets on one side of the oospore. This type of oospore structure could be easily recognized in Pythiopsis cymosa deBary, and P. humphreyana Coker, but not in Dick’s isolates of Scoliolegnia blelhaminsis and S. subeccentrica. The oospores of the latter two species are closer to subcentric type Ⅱ. In our isolate of Saprolegnia asterophora the subcentric type Ⅱ oospores were also observed and with somewhat small droplets compared to those of S. blelhaminsis and S. subeccentrica. We were convinced that S. blelhaminsis and S. subeccentrica seemed to be only subcentric type Ⅱ and rarely centric type. Based on above observation we suggest that these oospore structures did not seem to be significant enough for separating species as Dick applied in three species of Scoliolegnia. Our isolated of Saprolegnia asterophora showed a wide variation in several characters: the oogonium possessed from one to fourteen oospores, but mostly with 4-6, its oogonial wall papillae were regular to irregular and antheridia were rare. Like other member of Saprolegnia, our isolate is thin and unpitted oogonial wall. Besides based on oospore structure, Dick (1969b) separated Scoliolegnia asterophora, S. subeccentrica and S. blelhaminsis by their oospore number, the presence or absence of antheridia and oogonial wall papillation and sporangial renewal. Since our isolate showed such a wide variation in above mentioned characters which were derived from the came hyphae tip. We suspected that Dick was treating the same species of organism. Except with the papillate oogonia, the genus Scoliolegnia is difficult to separate from Saprolegnia and so Seymour (1970) has doubted the validity of genus Scoliolegnia.