Rafael F. Castañeda Ruiz

Two new dematiaceous hyphomycetes on Cyathea from Mexico

Belemnospora navicularia anam. sp. nov. and Hermatomyces amphisporus anam. sp. nov., two new taxa of hyphomycetes collected on a rotten branch of Cyathea sp. (a fern tree) in a Mexican forest are described and illustrated. B. navicularia is characterized by navicular, 3-septate conidia with brown central cells and paler ends. H. amphisporus is distinguished by two kinds of conidia, the first turbinate, gray brown towards the apex and hyaline at the lower cells and other type lenticular and black at the center as typical for the genus Hermatomyces. Keys to Belemnospora and Hermatomyces species are proposed.

New species of Lobatopedis and Minimelanolocus (anamorphic fungi) from a Mexican cloud forest

Abstract : Two new species in the genera Lobatopedis and Minimelanolocus were found during an investigation of anamorphic fungi from plant debris collected in a cloud forest in Veracruz State, Mexico. Both are described and illustrated. Lobatopedis kirkii sp. nov. is characterized by brown, macronematous conidiophores, monoblastic conidiogenous cells, and brown, cylindrical, narrowly obclavate to sub-acicular conidia which differ from those of other species of Lobatopedis in shape. Minimelanolocus limpidus sp. nov. is characterized by macronematous dark brown conidiophores, polyblastic conidiogenous cells with slightly melanized scars, and obclavate, (3–)6-septate, pale golden brown conidia. A comparative table and a key to Lobatopedis species are also provided. Key words : hyphomycetes, microfungi, nature conservation, taxonomy. Introduction Cloud forests (CF) are among the most diverse biomes in the world. In Mexico, this kind of forest, although covering less than 1% of the land surface, contains 10–12% of the country’s flowering plant species (Rzedowski 1996). Because of the climatological characteristics, all kinds of fungi grow in the wide variety of habitats provided by these forests. Unfortunately, CF are severely threatened not only in Mexico but also worldwide. Urgent exploration of the few remnants of such forests is therefore needed. As part of a long-term study of anamorphic fungi from cloud forests, multiple

A new species of Heliocephala from México with an assessment of the systematic positions of the anamorph genera Heliocephala and Holubovaniella

During a study of the microfungi on decaying leaves collected in México we encountered a fungus sharing features of the anamorph genera Heliocephala and Holubovaniella. This hyphomycete resembled Hol. elegans in possessing obclavate to fusiform, three-septate, rostrate phragmoconidia, but it can be distinguished by its much shorter, branched, determinate conidiophores. Unlike members of genus Heliocephala, which also possess determinant conidiophores, the phragmoconidia of this taxon are short-rostrate and have not been observed to germinate iteratively. Prompted by the discovery of this hyphomycete, we investigated the phylogenetic relationships among species of Heliocephala and Holubovaniella. Analysis of large subunit rDNA gene sequences positioned species of Heliocephala and Holubovaniella in the Dothideomycetes and identified Stomiopeltis betulae (Micropeltididaceae) as their closest relative. These results also indicated that Heliocephala and Holubovaniella are closely related taxa. Based on these findings and the similarity of the developmental and morphological characters of species of Heliocephala and Holubovaniella, we recognize these genera as synonymous and describe a new species, Heliocephala triseptata. A dichotomous key to the species of Heliocephala is provided.

Minteriella cenotigena anam. gen. & sp. nov. from submerged plant material in Mexico

Minteriella cenotigena gen. & sp. nov., found on decaying bark submerged in a sinkhole from the southern of Mexico, is described and illustrated. The new taxa is distinguished by synnematous conidiomata, with polyblastic, discrete, indeterminate, sympodially proliferating conidiogenous cells, with flat conidiogenous loci and cylindrical, 3- to 4- (to 5) euseptate, hyaline conidia.

Atrokylindriopsis, a new genus of hyphomycetes from Hainan, China, with relationship to Chaetothyriales

Atrokylindriopsis setulosa gen. et sp. nov. produces pigmented, septate, setulate conidia that are attached to the monophialidic conidiogenous cells of unbranched, brown, macronematous conidiophores at the midpoint of their long side during conidiogenesis, giving the appearance of a ‘T’. Internal transcribed spacer region (ITS) and partial 28S rDNA sequences indicate placement of Atrokylindriopsis in the Chaetothyriales.