T. W. Johnson

AQUATIC FUNGI OF ICELAND: PYTHIUM

SUMMARY Descriptive notes are given for the following species of Fythium recovered from soil and water in various localities in Iceland: P. debaryanum, P. dissotocum, P. echinulatum, P. gracile, P. inflatum, P. mamillatum, P. middletonii, P. monospermum, P. pulchrum, P. rostratur, P. tenue, P. torulosum, P. ultimum, P. undulatum, and P. vexans. A form of P. tenue is reported as a possible intermediate between this species and P. gracile, and a species (of the filamentous sporangiate series) lacking an antheridial apparatus is described but not named. Representatives of Pythium Pringsheim, particularly those forms that fail to produce the sexual apparatus in gross or pure culture, are common in Iceland. Earlier (13), four species were identified, and notes on two unnamed representatives were subsequently (11) published. In this paper I present a descriptive and taxonomic account of sixteen aquatic species of Pythium found in Iceland. One of the two unnamed taxa described in 1969 (11) is assigned to Hesses Pythium debaryanum on the basis of morphological evidence from cultures grown on hempseed. Save for the species occurring in algae, the fungi reported were isolated and propagated on potato dextrose agar (Difco, dehydrated). Subsequently, the isolates were grown on hempseed halves in sterile, distilled water, and characterized. Specimens preserved on slides are deposited in collections in the Museum of Natural History, Reykjavik. A key to the species of Pythium [exclusive of one unnamed taxon (11)] now known to occur in Iceland, follows.

A New Marine Ascomycete from Australia

Most marine pyrenomycetes are lignicolous, but some are epiphytic on marine phanerogims and algae. Meyers (1957) listed 30 species of algae known to be attacked by these fungi. A number of repOrts dealing with marine ascomycetes on algal hosts appeared before 1900, the most noteworthy being those of Winter (1887), and Jones (1898). Cotton (1908) described a pyrenomycete on Ascophyllum nodosum (L.) Le Jol. and summarized previous reports of ascomycetes found on algae. Reed (1902) collected two spe? cies, and Sutherland, in a series of papers (1914-1916), reported sev? eral alga-infesting pyrenomycetes. More recently, a number of asco? mycetes occurring on algae have been noted (Feldmann, 1957, 1958; Cribb & Herbert, 1954; Cribb & Cribb, 1955, 1960a, b; Wilson & Knoyle, 1961; Kohlmeyer, 1963). This report describes a heretofore unreported pyrenomycete col? lected from the marine alga, Ballia callitricha Ag. The material was obtained from Warrnambool, Victoria, in waters off southern Australia.

Aquatic Fungi of Iceland: Some Filamentous, Eucarpic, and Holocarpic Species

Some aquatic fungi from Iceland are described. Included in the account are: an Aphanomyces with ornamented oogonia; a variant of A. laevis; two members of Olpidiopsis, and Rozella septigena in Aphanomyces; an Apodachlya combining the characteristics of A. minima and A. pyrifera; an unidentified Leptolegniella and two unnamed species of Pythium from pine pollen; Rhizophydium pythii, and a parasite of R. sphaerotheca tentatively identified as Scherffels R. parasitans. Aphanomyces helicoides, A. scaber, Phlyctochytrium bullatum, P. papillatum, Rhizophydium pollinis-pini, R. globosuim, and R. carpophilum are reported, and an imperfectly known fungus having characteristics of Phlyctochytrium longicollum and Rhizidiomyces apophysatus is discussed.

Aquatic Fungi of Iceland: Comparative Morphology of Achlya Radiosa, A. Pseudoradiosa, And A. Stellata

Among the watermolds occurring in Iceland (8, 11), Achlya radiosa Maurizio (12) and A. stellata deBary (2) are surprisingly common. Neither species has been reported from North America, hence knowledge of them is based largely on European material. Of the two, A. radiosa is most easily recognized, though its taxonomic history is not unblemished with other names (10). Rogers and Beneke (15) noted the close resemblance of A. pseudoradiosa Rogers & Beneke to A. radiosa, but separated their species from Maurizios largely on o6spore number and size. Until the authoritative account by Dick (6) Achlya stellata was poorly defined, and the species had been treated (10) as a doubtfully valid taxon. Achlya stellata was cited in connection with A. pseudoradiosa, and considered (15) to be very closely allied to it. The Icelandic specimens of Achlya radiosa and A. stellata were variable in some prominent features. The degree of variation was explored, and for comparative purposes, we characterized the structure of specimens in cultures of A. pseudoradiosa (from Brazil; 3, 16). The resulting information was then applied to the systematics of the three species.

Resting Spore Germination in Three Chytrids

The resting spore of Phlyctochytrium planicorne enlarges within a resting sporangium, distends it, and discharges endogenously cleaved planonts which cluster at the orifice. In P. aureliae, the res...

Fungi in Planktonic Synedra from Brackish Waters

Nine species of fungi are known to occur on various species of Synedra (Sparrow, 1960: 1086). Of these, Ectrogella perforans Peter? sen, E. licmophorae Scherffel, and E. eurychasmoides J. & G. Feldmann are known from strictly marine habitats, occurring in species of Licmophora. In 1962 and 1964 specimens of Synedra infected by fungi were collected in three brackish water areas of one North Carolina estuary. This paper reports these fungi. Inasmuch as two of the fungi occurred in a rather unusual habitat, a brief statement on major features of the collection sites is given. A more or less regular collection program for fungi in the Neuse River of Eastern North Carolina has been under way since 1955. In 1956, seven promi? nent station sites were established along a salinity gradient in this estuary. Monthly or bimonthy samplings for various fungi have been made since 1956, and in 1962 these same stations became the sites for either regularly or intermittently scheduled plankton tows. Salinity, temperature and pH of the waters at these stations have been determined at each sampling since 1956, and in the years 1958-1960, dissolved oxygen, nitrate and phosphate tests were also made. Thus, rather complete records of major environmental factors are extant. The fungi reported in this paper were each found once at one of three stations in the estuarine system. Flanners Beach Station is near the uppermost reaches of the estuary. Salinity ranges here from 7.816.9%c, but predominates in the region of 8-11%C. Adams Creek Station, some six nautical miles east of Flanners Beach has had, in nine years, a salinity range of 7-23.1%0 (predominantly 12-17%c), while the Core Creek Station three nautical miles nearer the mouth of the estuary has had a somewhat higher range: ll-26.5%c, generally 18-23%c. Diurnal tidal cycles are evident at all three stations, but the highest amplitude is at Core Creek. Although Synedra species are to be found in the fresh-water sector of the river, they are not thus far known to be infected by fungi.

Saprolegniaceae: a keratinophilic Aphanomyces from soil.

Specimens of Aphancmyces laevis de Bary f. keratinophilus Ookubo & Kobayasi, recovered from soils in various South Pacific Islands and in Iceland, are described and the form is raised to specific r...

Two Unusual Chytridiaceous Fungi

Two uniflagellate, monocentric, eucarpic chytrids having in common a branched, lobed, and digitate pattern of growth are reported. The full extent of the endobiotic system of the fungi was not observed, hence assignment of them to Phlyctidium and Phlytochytrium is provisional. Observations on the developmental morphology of the fungi, though fragmentary, are recorded, and the taxonomic implications are discussed. Binomials are not applied since neither fungus could be fully characterized.

Marine Fungi. III. Phycomycetes

To the pioneer work of Petersen (1905) and Sparrow (1934) on marine Phycomycetes have recently been added extensive studies by Aleem (1953) and Kobayashi and Ookubo (1953, 1954). Hohnk (1939, 1953) and Hohnk and Aleem (1953) have contributed exten? sively to our knowledge of brackish-water Phycomycetes. Largely as the result of Sparrows study (1936), the marine Phycomycetes of the Northeastern seaboard of the United States are well-known. A report of Rhizophydium polysiphoniae by Martin (1922) and the description of Anisolpidium ectocarpii by Karling (1943) apparently constitute the only additional records of algal-inhabiting marine Phycomycetes from the East Coast. The present paper is a report on some marine Phyco? mycetes collected in the Beaufort Inlet region, Beaufort-Morehead City, North Carolina, during the spring and summer of 1955 and 1956. Paucity of material and failure to observe planonts and other critical phases in development, have prevented positive identification of several fungi. In the interest of completeness, however, these fungi are de? scribed insofar as possible. Collections of marine algae on or in which the Phycomycetes were observed, were generally made from rock jetty habitats, or by scraping attached algae from buoys and driftwood debris. Hydrometric salinity determinations were made at each collection site, both at low and high tide. The lowest salinity determined was 33.6%c. Collections were examined within 24 hours after they were made, or after temporary storage at 5? C.

A Brief Historical Survey of Fungal Taxonomy and Floristics in China

SUMMARY The major contributors, from 1775 to 1980, by Chinese and foreign mycologists to the taxonomy of fungi in China are reported. During this period, taxonomic studies by 27 foreign and more than 90 Chinese scholars resulted in over 900 publications. Of these accounts, 110 were monographs (generic or familial), and 14 were compilations or general works. All major groups of fungi are represented in the Chinese mycoflora. Most emphasis by Chinese mycologists has been on the collection and identification of the Uredinales, Ustilaginales, and Erysiphales.