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The leaf spot disease of Pongamia pinnata caused by an asperisporium-like asexual morph, which is usually referred to as Asperisporium pongamiae, is quite common during monsoon seasons in India. Phylogenetic analyses, based on LSU and rpb2 sequence data, and blast searches using ITS sequence data, revealed that this ascomycete forms a lineage within Mycosphaerellaceae distant from all other generic lineages. Pedrocrousiella gen. nov., with P. pongamiae comb. nov., based on Fusicladium pongamiae (≡ A. pongamiae), as type species is introduced for this lineage. This species has been considered the asexual morph of Mycosphaerella pongamiae (≡ Stigmatea pongamiae). However, this connection is unproven and was just based on the occasional association of the two taxa in some collections. Several attempts to induce the formation of a sexual morph in culture failed, therefore the putative connection between these morphs could not be confirmed. Asperisporium pongamiae-pinnatae is reduced to synonymy with P. pongamiae. Asperisporium pongamiae-pinnatae was introduced because of the wrong assumption that F. pongamiae had been described on another host, Pongamia globosa. But Fusicladium pongamiae was actually described in India on Pongamia glabra, which is a synonym of P. pinnata, and hence on the same host as Asperisporium pongamiae-pinnatae . Pedrocrousiella pongamiae clusters in a clade containing Distocercospora, Clypeosphaerella , and "Pseudocercospora "nephrolepidicola, a species which is not congeneric with Pseudocercospora. Phylogenetically, Pedrocrousiella is distant from the Asperisporium s. str. clade (type species A. caricae), which is more closely related to Amycosphaerella, Pseudocercosporella, Distomycovellosiella and Nothopassalora.

The species-rich family Mycosphaerellaceae contains considerable morphological diversity and includes numerous anamorphic genera, many of which are economically important plant pathogens. Recent revisions and phylogenetic research have resulted in taxonomic instability. Ameliorating this problem requires phylogenetic placement of type species of key genera. We present an examination of the type species of the anamorphic Asperisporium and Pantospora. Cultures isolated from recent port interceptions were studied and described, and morphological studies were made of historical and new herbarium specimens. DNA sequence data from the ITS region and n LSU were generated from these type species, analysed phylogenetically, placed into an evolutionary context within Mycosphaerellaceae, and compared to existing phylogenies. Epitype specimens associated with living cultures and DNA sequence data are designated herein. Asperisporium caricae, the type of Asperisporium and cause of a leaf and fruit spot disease of papaya, is closely related to several species of Passalora including P. brachycarpa. The status of Asperisporium as a potential generic synonym of Passalora remains unclear. The monotypic genus Pantospora, typified by the synnematous Pantospora guazumae, is not included in Pseudocercospora sensu stricto or sensu lato. Rather, it represents a distinct lineage in the Mycosphaerellaceae in an unresolved position near Mycosphaerella microsora.

A survey of the fungi associated with the tropical weed Mikania micrantha was conducted during 1988 and 1989 in part of its native range in southern Brazil. Sampling was concentrated mainly in the state of Rio de Janeiro, covering 70 sites in different climatic or ecological zones. Nine species were identified, including the recently described downy mildew species Basidiophora montana and the previously undescribed Mycosphaerella mikania-micranthae sp. nov. with its anamorph Septoria mikania-micranthae. Asperisporium mikaniae comb. nov., Asperisporium mikaniigena comb. nov., Pseudocercospora plunketii comb. nov., and Cercospora mikaniacola are new records for Brazil. Field observations indicate that Basidiophora montana has potential as a classical biological control agent of the weed in Old World subtropical or montane climates, whilst Mycosphaerella mikania-micranthae and the microcyclic rust Puccinia spegazzinii appear to be equally damaging to the host but to have a wider climatic range and thus are highly promising agents for introduction throughout the Palaeotropics.

Four Cercospora taxa from conifers are described, illustrated and reassessed in relation to their generic placements. Cercospora sequoiae and C. juniperina are referred to Asperisporium and C. exosporioides and C sequoiae var. juniperi to Pseudocercospora. Anaphysmene cupressi sp. nov. is illustrated and described from needles of Cupressus lusitanica from Guatemala and characterized by semi-immersed to superficial sporodochial conidiomata and hyaline, cylindrical, 10-14-septate, guttulate conidia. A key to "Cercospora-likz" fungi on conifers is given.