ACTINOPLANACEAE 



313 



light ochraceous-salmon margin. Sporangia 

 usually on the smooth areas, none on the 

 elevated parts; formed on palisade hyphae. 



Potato-glucose agar: Growth good to 

 very good. Central area with coarse con- 

 volutions or large bumps and irregular 

 ridges separated by radial grooves which 

 slope to the smooth distinct margin. Surface 

 glossy. Color apricot-orange to russet, be- 

 coming gray in old cultures. Soluble pigment 

 darkens the agar. Sporangia formed on the 

 margin of some cultures, absent in most. 

 Palisades formed. 



Nutrient agar: Growth fail-. Center 

 slightly elevated and with a wide flat margin. 

 Color ochraceous-orange to cinnamon-rufous. 

 Sporangia very rarely formed. Palisade 

 hyphae usually not distinct. 



( iclatin: Liquefied. 



Habitat: Soil from Philippine Islands; 

 also found in African soils and in marshland 

 soils in ( iormany. 



Remarks: This species is characterized 

 by the predominantly spherical sporangia 

 usually on long unbranched stalks, the 

 rather poor and usually fiat growth on 

 synthetic agar, and the very distinct palisade 

 hyphae on this medium. The dark brown 

 diffusible pigment on potato-glucose agar is 

 also characteristic. 



Genus Streptosporangium Couch 



Occurs on sterilized leaves of Paspalum 

 grass in water, forming an inconspicuous 

 mycelium which overgrows the leaves, and 

 an aerial mycelium which grows in scattered 

 or concentrically arranged tufts. The aerial 

 mycelium is white to pinkish on the leaves; 

 hyphae are much branched, sparingly sep- 

 tate, and about 0.5 to 1.2 id in diameter. On 

 some media, sporangia are formed abun- 

 dantly in the aerial mycelium. Spores are 

 abundant in the sporangia, without flagella, 

 and are nonmotile. Growth poor to good on 

 a variety of semisolid media (Fig. 64). 



lour cultures, representing three distinct 



species, were found 

 Two of the species 

 by the soil dilution 

 from dog manure. 



The type specie 

 rost uni ( 'ouch. 



ompnse t bis genus. 

 1 isolated from soil 

 hod and the third 



Streptosporangium 



Streptosporangium r<>s<uin ('ouch, 1!).").") 

 (Couch, J. X. J.Elisha Mitchell Sci. Soc. 71, 

 148, 1955). 



.Morphology: Grows on sterile leaves, 

 either in soil water or on damp sterile soil, 

 forming a substrate mycelium which spreads 

 over the surface of the leaf, not penetrating 

 or decolorizing it; it also spreads over the 

 soil. Aerial mycelium white at first, changing 

 to pale pink; it appears as single hyphae or 

 as minute tufts which grow to form mounds 

 up to 2 mm across, arranged more or less in 

 concentric circles. Sporangia first appeal- on 

 scattered single hyphae, apical on the main 

 thread or on short, lateral branches, a fvw 

 to many sporangia on one hypha. The 

 sporangia are white in small groups, pink in 

 large masses; spherical, 7 to 1!) p. in diameter. 

 Shortly after their formation, spores are 

 visible as a single coil in each sporangium; 

 when completely formed, they are irreg- 

 ularly arranged. Immersion of the mature 



Figi be 65. Streptosporangium isolated from 

 forest litter (Reproduced from: Van Brummelen, 

 J. and Went. .]. V. Labor. Microb. Univ. Amster 

 dam 2;?: 391, 1957 , 



