E. Descals

Taxonomic studies on aquatic hyphomycetes: III. Some new species and a new combination

Two new anamorph-genera of ‘aquatic hyphomycetes’ are erected: Tricladiopsis , to accommodate T. foliosa sp.nov. (type species) and T. flagelliformis sp.nov., and Sympodiocladium , with S. frondosum sp.nov. as sole representative. Other new anamorph species are: Articulospora atra, Flabellospora acuminata, Isthmotricladia britannica, Scorpiosporium rangiferinum, Sigmoidea aurantiaca, Sporidesmium ensiforme, Tricellula botryosa and Dwayaangam cornuta . Tetracrium amphibium is transferred to Flabellospora .

Teleomorphs of three aquatic hyphomycetes

The teleomorphs of Tricladium splendens, Articulospora tetracladia and Dimorphospora foliicola are described and illustrated. They are respectively Hymenoscyphus splendens n.sp., Hymenoscyphus tetracladius n.sp. and Hymenoscyphus foliicola n.sp.

Leptosporomyces galzinii, the basidial state of a clamped branched conidium from fresh water

Cultures derived from a branched, clamped conidium collected from stream foam have produced a basidial stage identified as Leptosporomyces galzinii (Bourd.) Julich. Another isolate from submerged decaying Acer leaves produced the imperfect state, the development of which is described.

Four new staurosporous hyphomycetes from mountain streams

Four staurosporous hyphomycetes isolated from conidia in foam in British streams are described from pure culture: Dendrospora moniliformis sp.nov., Enantioptera tetra-alata gen. et sp.nov., Tetracladium furcatum sp.nov. and Tricladium curvisporum sp.nov.

Taxonomic studies on aquatic hyphomycetes II. The Dendrospora aggregate

Neotypes are proposed for the type species, Dendrospora erecta Ingold, and for D. juncicola Iqbal. The genus concept is extended to include the latter and five other recently isolated species: D.fusca n.sp., D. torulosa n.sp., D. tenella n.sp., D. nana n.sp. and D.fastuosa n.sp. Affinities among these and with species in allied form genera are discussed. An artificial key is provided.

The Hymenoscyphus teleomorph of Geniculospora grandis

Single-ascospore cultures of Hymenoscyphus africanus sp.nov. from decaying tree leaves, when submersed in water, yielded conidia of the Ingoldian hyphomycete Geniculospora grandis.

Variations in asexual reproduction in species of Entomophthora on aquatic insects

The asexual reproduction of Entomophthora conica and E. rhizospora , both of which infect aquatic insects, is described. E. conica has four different kinds of conidia, two aerial and two aquatic (believed to be adaptations to underwater dispersal, and possibly to infection of different stages of the insect hosts). E. rhizospora has two types of aerial conidia, and on germination under water either may develop multipolar germ-tubes to form a multi-radiate propagule.

Branched aquatic conidia in Erynia and Entomophthora sensu lato

Two members of the Entomophthoraceae (Erynia plecopteri sp.nov. on Nemouridae, Plecoptera, and Entomophthora cf. thaxteri, on Tipulidae, Diptera) were found on cadavers of adult insects from lotic habitats. In both species aerial primary conidia are unbranched and replicate into progressively smaller conidia. Aquatic primary conidia are coronate and produce stellate secondary conidia. Submerged aerial conidia produce stellate forms, and conversely when aquatic conidia are exposed to air they produce conidia of the aerial type. Aerial conidia of Entomophthora gigantea undergo multipolar germination under water.

Taxonomic studies on aquatic hyphomycetes IV. Pure culture and typification of various species

Criteria based on ontogeny are given for clear distinctions between Culicidospora aquatica and C. gravida. Polycladium equiseti, Tricladium castaneicola and T. patulum, and the phialidic states of T. splendens and T. terrestre, believed to be spermatial, are described from pure culture. A lectotype is proposed for T. angulatum.

Occurrence of Infundibura adhaerens in aquatic habitats in Britain

Infundibura adhaerens , a sporodochial hyphomycete with naviculate conidia and infundibuliform appendages at each end, is described from Quercus and Pinus litter in shallow ponds in Britain.