False Bean Smut Caused by Slime Mold.

Identification of the "bean smut" reported in 1998 in abstracts from two conferences was later disseminated by a Plant Disease Note; citations in books, papers, and blogs; and in several official sites, including databases curated by the United States Department of Agriculture and Embrapa-Brazil. After seeing the illustration of the syndrome in 2002, the need became clear for a review of the so-called bean smut. Field collections indicated that it is common in no-till bean and soybean farming in Brazil. Our studies revealed that the "bean smut" attributed to Ustilago sp. or "Ustilago phaseoli" and, later, to "Microbotryum phaseoli" is not a real smut but is Physarum cinereum (Physaraceae, Physarales, Myxomycetes), sporulating superficially on leaves, stems, and pods of dry bean and soybean. To unravel this imbroglio, we produced detailed morphological documentation supported by molecular treatment. This will correct the spread and further incorporation of an error in the literature based upon mistaken taxonomical work related to a plant-associated nonpathogenic organism.

ITS phylogeny and taxonomy of Phyllachora species on native Myrtaceae from the Brazilian Cerrado.

Nine Phyllachora species found on hosts belonging to the family Myrtaceae native to the Brazilian Cerrado were described and illustrated. We sequenced nuc rDNA internal transcribed spacer barcode regions for representatives of seven species and conducted phylogenetic analyses, which provided strong support for four new species that we describe as Phyllachora cerradensis, P. ermidensis, P. furnasensis, and P. myrciariae. Catacauma nigerrimum was recombined into P. nigerrima, and a key to the common Phyllachora species on myrtaceous hosts from the Brazilian Cerrado was also included.

Austropuccinia licaniae, first congeneric with the myrtle rust pathogen A. psidii.

In 1895 and 2001, rust fungi affecting Licania trees (Chrysobalanchaceae) in Brazil were described as Uredo licaniae by Hennings in the state of Goiás and as Phakopsora tomentosae by Ferreira et al. in the state of Amazonas, respectively. Recently, a Licania rust fungus collected close to the Amazonian type location sharing symptoms with the former two species was subjected to morphological examinations and molecular phylogenetic analyses using 28S nuc rDNA (ITS2-28S) and cytochrome c oxidase subunit III (CO3) gene sequences. Since the original type specimen of Ph. tomentosae is considered lost, we carefully reviewed the type description and questioned the identity of the telium, which justified the description of the fungus as a Phakopsora species. Furthermore, the additional revision of the type material described by Hennings revealed that Ph. tomentosae is a synonym of U. licaniae. Based on the morphological examinations, disease symptoms, and shared hosts, we concluded that the newly collected material is conspecific with U. licaniae. However, the phylogenetic analyses rejected allocation in Phakopsora and instead assigned the Licania rust fungus in a sister relationship with Austropuccinia psidii (Sphaerophragmiaceae), the causal agent of the globally invasive myrtle rust pathogen. We therefore favored a recombination of U. licaniae (syn. Ph. tomentosae) into Austropuccinia and proposed the new name Austropuccina licaniae for the second species now identified for this genus. The fungus shares conspicuous symptoms with A. psidii, causing often severe infections of growing leaves and shoots that lead to leaf necrosis, leaf shedding, and eventually to the dieback of entire shoots. In view of the very similar symptoms of its aggressively invasive sister species, we briefly discuss the current state of knowledge about A. licaniae and the potential risks, and the opportunity of its identification.

Cerradopsora, a new genus of neotropical rust fungi.

Two Cerrado rust fungi, Phakopsora rossmaniae and Aplopsora hennenii, described in 1993 and 1995 and originally assigned to families Phakopsoraceae and Ochropsoraceae, respectively, were subjected to molecular phylogenetic analyses using fragments of the nuc 28S and 18S rDNA and mitochondrial cytochrome c oxidase subunit 3 (CO3) gene. Although both taxa were morphologically well placed in their original genera, they were shown to belong in a strongly supported new lineage within the Raveneliineae distant from the Phakopsoraceae and Ochropsoraceae. Therefore, we properly treated this lineage as the new genus Cerradopsora now harboring C. rossmaniae (type species) and C. hennenii. However, this novel phakopsoroid genus remains in uncertain familial position without support to be included in any of the families that share space within the Raveneliineae.

Raveneliopsis, a new genus of ravenelioid rust fungi on Cenostigma (Caesalpinioideae) from the Brazilian Cerrado and Caatinga.

The multicellular discoid convex teliospore heads represent a prominent generic feature of the genus Ravenelia. However, recent molecular phylogenetic work has shown that this is a convergent trait, and that this genus does not represent a natural group. In 2000, a rust fungus infecting the Caesalpinioid species Cenostigma macrophyllum (= C. gardnerianum) was described as Ravenelia cenostigmatis. This species shows some rare features, such as an extra layer of sterile cells between the cysts and the fertile teliospores, spirally ornamented urediniospores, as well as strongly incurved paraphyses giving the telia and uredinia a basket-like appearance. Using freshly collected specimens of Rav. cenostigmatis and Rav. spiralis on C. macrophyllum, our phylogenetic analyses based on the nuc 28S, nuc 18S, and mt CO3 (cytochrome c oxidase subunit 3) gene sequences demonstrated that these two rust fungi belong in a lineage within the Raveneliineae that is distinct from Ravenelia s. str. Besides proposing their recombination into the new genus Raveneliopsis (type species R. cenostigmatis) and briefly discussing their potentially close phylogenetic affiliations, we suggest that five other Ravenelia species that are morphologically and ecologically close to the type species of Raveneliopsis, i.e., Rav. corbula, Rav. corbuloides, Rav. parahybana, Rav. pileolarioides, and Rav. Striatiformis, may be recombined pending new collections and confirmation through molecular phylogenetic analyses.

Filling a gap in the taxonomy of phyllachoroid fungi: Proposition of Neopolystigma, gen. nov., and the new family Neopolystigmataceae.

A Polystigma-like found on an herbaceous to shrubby species of Fabaceae (Andira humilis) in the Brazilian Cerrado was morphologically close to Polystigma pusillum, a leaf parasite on Andira inermis collected in Central America and Brazil. Phylogenetic analyses using a combination of the rDNA 28S, 18S, and internal transcribed spacer (ITS) regions placed both fungi in the Phyllachorales, and not in Polystigamataceae/Xylariales, where Polystigma species belong, and characteristically found on members of the Rosaceae, causing red leaf blotch containing bright-colored fungal stromata spread on the lesions. This disease prevails in orchards in the Northern Hemisphere, infecting Amygdalus, Cerasus, Padus, and Prunus species, but never in the Tropics. Polystigma species infecting other botanical families have been reallocated in different families, orders, and even classes in Ascomycota. In our phylogenetic analyses, the two species on Andira were allocated in Phyllachorales but separated in a well-supported cluster from Phyllachoraceae and Phaeochoraceae. In relation to Telimenaceae, the statistical support is not strong; however, considering that its type genus, Telimena, was never sequenced, we choose to accept Neopolystigma (type N. saraivae) as the type genus of a new family, Neopolystigmataceae. The sister species of N. saraivae, Polystigma pusillum found on A. inermis, was recombined into N. pusillum.

Reinstatement and phylogenetic allocation of the palm rust genus Cerradoa in the Pucciniaceae, and establishment of Pseudocerradoa, gen. nov.

The genus Cerradoa (type species Cerradoa palmaea) was established in 1978 by Hennen and Ono and named after the Brazilian Cerrado biome. The holotype collected in Planaltina, Federal District, Brazil, belonged to the first rust fungus reported on palms (Arecaceae). For decades, the status of Cerradoa as a distinct genus has been regarded as doubtful, representing a synonym of Edythea (Uropyxidaceae) starting with the second edition of the Illustrated Genera of Rust Fungi in 1983. Our molecular phylogenetic analyses, as well as our morphological investigations, allowed us to reject this synonymy, leading to the reinstatement of Cerradoa within the Pucciniaceae. Cerradoa, together with morphologically similar genera such as the newly established Pseudocerradoa with two species (Ps. paullula and Ps. rhaphidophorae) infecting araceous hosts, the fern rust Desmella, and also P. engleriana, could not be assigned to any of the seven identified major lineages within the Pucciniaceae. Edythea, instead of being maintained as a member of the Uropyxidaceae, was herein placed in Pucciniaceae, shown phylogenetically in close relationship to Cumminsiella mirabilissima, both infecting the Berberidaceae. Additionally, our extensive phylogenetic analyses add guidance for future taxonomic revisions in the highly polyphyletic genus Puccinia and other established taxa within the family Pucciniaceae.

Uromyces hawksworthii nom. nov. for Aecidium goyazense, on Phthirusa stelis (Loranthaceae) from the Brazilian Cerrado.

The sexual morph of Aecidium goyazense collected in the Brazilian Cerrado was morphologically characterized by light microscopy and SEM, and shown to be a species of Uromyces, for which the name Uromyces hawksworthii nom. nov. is introduced, and designated as its epitype. This is the second Uromyces species known to infect the tropical genus Phthirusa (Loranthaceae). DNA sequences were generated from the ITS and 28S rRNA (LSU) regions of DNA recovered from aeciospores as well as teliospores. This fungus is compared with other Uromyces species known from Loranthaceae.

New hyphomycete genera on Qualea species from the Brazilian cerrado.

As part of studies on cerrado fungi three new hyphomycetes are described in association with trichomes on leaves of native species of Qualea (Vochysiaceae). These are: Trichomatomyces gen. nov. (type species: T. byrsonimae comb. nov.), Trichosporodochium gen. nov. (type species: T. cerradensis sp. nov.), and Phaeoidiomyces gen. nov. (type species: P. qualeae).

Hyphomycetes on the Vochysiaceae from the Brazilian cerrado.

New hyphomycetes are described in association with leaves of native plants of the family Vochysiaceae, as part of studies of cerrado fungi. Six new species are described belonging to genera Alternaria (A. qualeae sp. nov.), Janetia (J. salvertiae sp. nov.), Passalora (P. qualeae sp. nov.) and Periconiella (P. longispora sp. nov., P. qualeae-grandiflorae sp. nov. and P. campo-grandensis sp. nov.). A key to the species of Periconiella on Qualea is provided.

An overlooked source of fungal diversity: novel hyphomycete genera on trichomes of cerrado plants.

Eight monotypic hyphomycete genera new to science are described from the trichomes of native plants growing in the cerrado of Brazil: Trichomatoclava cerradensis, Echinoconidiophorum cerradense, Globoconidiopsis cerradensis, Globoconidium cerradense, Helminthosporiomyces cerradensis, Trichomatosphaera [corrected] cerradensis , Phragmoconidium cerradense, and Vesiculohyphomyces cerradensis gens. spp. nov. Two of the new genera were found on hosts belonging in Myrtaceae, and one of each of the following families: Icacinaceae, Malphigiaceae, Fabaceae, Dilleniaceae, Chrysobalanaceae, and Caryocaraceae. These discoveries suggest that the trichomes of neotropical plants are an unexplored source of novel fungal diversity, and merit more attention in biodiversity surveys.