14 



DUNN AND REYNOLDS 



TABLE 1 (cont'd) 



Family TUBERCULARIACEAE 

 Cvlindrocarpon sp.: Dunn, 1973. 

 Fusarium episphaeria (Tode) Fr.: Dunn, 1973. 

 Fusahurn solani (Mart.) Sacc: Dunn, 1973. 

 Fusarium sp.: Dunn, 1973. 



Metarrhizium anisopHae (Metschn.) Sorok.: Dunn, 1973. 

 Miirothecium roridum Tode ex Steudel: Dunn, 1973. 

 Mi^rothedum striatisporum Preston: Dunn, 1973. 

 Class BASIDIOMYCOTINA 

 Unidentified air isolate. 



"New Enewetak Atoll record. 



Kohlmeyer, 1979). None of the fungi isolated from 

 Enewetak, therefore, fits the definition of a marine fungus. 

 Inhibitors in seawater (Kirk, 1980) and in soil (Lockwood, 

 1977) may prevent fungal spores from germinating until 

 changes occur in the endogenous or exogenous nutrient 

 status or until the exogenous sp>ore inhibitors are removed. 

 The exogenous inhibitors of nonmarine fungi can be p>artly 

 removed or deactivated by autoclaving seawater; most 

 marine fungi can germinate in raw seawater. Addition of 

 glucose can also counteract the inhibition (Kirk, 1980). 



Few studies have been done on decomposition of sub- 

 tidal substrate. In a study of seagrass, Thalassia testudinum 

 Konig, Newell and Fell (1980) showed that although non- 

 marine fungi were present, they played only a minor role 

 in decomposition of T. testudinum leaves until the leaves 

 were deposited in the intertidal. The terrestrial fungi are 

 active in the intertidal zone, but their significance in rela- 

 tion to marine fungi is unknown (Newell and Fell, 1980, 

 1982). On the basis of the present discussion, it can be 

 suggested that the fungal propagules in Enewetak Atoll 

 beaches are also dormant until they come in contact with a 

 proper substrate. 



Fungi from the beaches of Enewetak Atoll have been 

 compared with those from other locations. When the 

 specimens isolated by Dunn (1973) were compared with 

 fungi plated from sediment of a coastal estuary of North 

 Carolina with salinities from to 36°/oo (Borut and John- 

 son, 1962), a Dice similarity quotient of 17% was found, 

 indicating a distinct biota for these two very different 

 marine habitats. 



In a comparison of the fungi isolated by Warcup plat- 

 ing from beaches at Enewetak Island and the Hawaiian 

 Islands, a Dice similarity quotient of 43% was found (Dunn, 

 1973). The beaches in the Hawaiian Islands are both vol- 

 canic and carbonate, whereas the beaches at Enewetak 

 Island are carbonate. Similarity is greater between the 

 mycobiota of the carbonate beaches in Enewetak and 

 Hawaii (48%) than between the carbonate and volcanic 

 beaches in Hawaii (41%). The principal difference between 

 the mycobiota of the carbonate beaches sampled in 

 Enewetak and those in Hawaii was the abundance of 

 species present in both beaches relative to the total iso- 

 lates. Typical of the pattern are Gvmnoascus reesii 



Baranetsky and two species in the genus Microascus, 

 which were common at Enewetak Island beach but were 

 infrequently isolated from Kahala Beach, Oahu, Hawaii. 



CHYTRIDIOMYCOTINA 



The isolates of this class were all unicellular. 

 Rhizophi;ctis rosea (DeBary and Woronin) Fischer was the 

 most common isolate, and it is the most widespread of all 

 chytrids (Sparrow, 1960). Unicellular chytrids were found 

 in the beach areas by Dunn (1973) but were not identified. 

 Sparrow (1948) consistently found only the same three 

 species of this class on Enewetak and on three other 

 Marshall Island atolls. The filamentous sp>ecies of the class 

 were conspicuously absent. 



OOMYCOTINA 



Although many sjjecies in this class are common plant 

 pathogens and would be expected to be associated with 

 the vegetation, none has been reported from this atoll. 

 They may be too sensitive to salinity to do well in beach 

 habitats (TeStrake, 1959; Lee and Baker, 1972), although 

 some have been isolated from other beach areas. 



ZYGOMYCOTINA 



Conidiobolus sp. was isolated from subtidal areas on 

 Enewetak. Species in this genus are normally associated 

 with dung of insect-eating animals or decaying vegetation. 

 This species was isolated only from seawater sources and 

 seems to require salinity. It does not resemble any 

 described species and does not last many generations in 

 culture. Members of the order Mucorales are common iso- 

 lates from beaches at Enewetak but have salinity optima 

 more appropriate for terrestrial species (Dunn, 1973). 



ASCOMYCOTINA 



Many ascomycetes are known to produce two types of 

 spores: the teleomorph, or sexual state, and the 

 anamorphs, or asexual states. The teleomorph may be 

 associated with one or more anamorphs. The teleomorph 

 genus regularly associated with the isolated Scopuhriopsis 



