Aseptate Ascospores Research Articles

First Report of Tar Spot on Corn Caused by Phyllachora maydis in Georgia, United States.

Tar spot is a major foliage disease of corn (Zea mays) caused by the fungus Phyllachora maydis. This disease can reduce the quality of silage, stover, husks, and grain (Valle-Torells et al. 2020). It was identified in the United States for the first time in 2015 in northern Illinois and Indiana (Ruhl et al. 2016). As of 2020, it has also been confirmed in Iowa, Michigan, Wisconsin, Ohio, Florida, Missouri, Minnesota and Pennsylvania (Telenko et al. 2020, Collins et al. 2021). In early August 2021, tar spot symptoms and signs were observed in late-planted, hybrid corn in southwestern Georgia in both Tift and Calhoun Counties. Where it occurred, incidence was nearly 100% and severity ranged from approximately 1% to 20% leaf coverage. As of November 2021, Tar spot has been confirmed in 13 counties throughout South Georgia. The symptoms on leaves were chlorotic lesions and the signs were black, raised, circular to irregular-shaped structures (stromata or clypei) ranging from 0.2 mm to 8 mm on the surface of the leaves. The stromata were present on both green and necrotic leaf tissue. Southern corn rust (Puccinia polysora) was often, but not always observed on leaves with tar spot. Microscopic observations of stromata included single and clustered ascomata (60 × magnification) that contained cylindrical, unitunicate asci with ellipsoid, hyaline, aseptate ascospores and abundant filiform paraphyses (400 × magnification). For molecular confirmation, stromata were surface sterilized with 95% ethanol and separated from the leaf tissue, then DNA was extracted using the Qiagen DNeasy Plant Mini-Kit (Qiagen, Inc., Valencia, CA). PCR was conducted with the universal ITS1 and ITS4 primers to amplify the internal transcribed spacer (ITS) region of the rDNA. The amplicons were Sanger sequenced (Genewiz, Inc., South Plainfield, NJ) and a consensus sequence of a representative lesion was deposited in GenBank (accession number OK649959). Using the BLASTN algorithm our sequence shared 100% and 99.2% coverage, and 97.2% and 98.4% similarity to P. maydis GenBank accessions MG881848 and MK184990, respectively. Phyllachora maydis is an obligate parasite that cannot be cultured, so Koch's postulates were not performed. Inoculum of P. maydis may have been transported to Georgia from Florida by wind or other weather events, but this has not been confirmed.

Mitrula aurea sp. nov., A New Aero-Aquatic Species from the Republic of Korea

The genus Mitrula (Mitrulaceae, Helotiales), as also known as swamp beacons, inhabits submerged, decaying vegetation in standing or decaying needles, twigs, leaves, and shallow water. They play an important role in carbon cycling in some freshwater ecosystems. In the herbarium of the Korea National Arboretum (KH), seven Mitrula specimens were collected during mushroom forays in the period from 2019 to 2021. The Korean collections were found to be macromorphologically closely related to M. paludosa and M. elegans, but micromorphologically they could be distinguished by characteristics of slightly narrower asci and aseptate ascospores. Our molecular phylogenetic analyses of the internal transcribed spacer (ITS) and 28S rDNA regions also revealed that our specimens were related to M. paludosa and M. elegans, but formed a distinct clade. Based on these results, we reported our specimens as new to science and discussed the phylogeny and diversity of Mitrula species.

<p><strong><em>Rhexocercosporidium camporesii sp. nov.</em> (Ploettnerulaceae, Helotiales) from Italy</strong></p>

A new species, Rhexocercosporidium camporesii was collected from dead branches of Scabiosa maritima (Caprifoliaceae) in Forlì-Cesena, Italy. The new species is characterized by a lack of setae surrounding the apothecia and by fusiform, aseptate ascospores containing multiple guttules. Rhexocercosporidium camporesii has larger asci and ascospores than other species of Rhexocercosporidium. Phylogenetic analyses using a combined gene analysis of LSU and ITS sequence data indicated that the new species belongs to Ploettnerulaceae (Helotiales). A detailed morphological description and illustration of the new species are provided.

Phylogenetic placement of Iodosphaeriaceae (Xylariales, Ascomycota), designation of an epitype for the type species of Iodosphaeria, I. phyllophila, and description of I. foliicola sp. nov.

The Iodosphaeriaceae is represented by the single genus, Iodosphaeria, which is composed of nine species with superficial, black, globose ascomata covered with long, flexuous, brown hairs projecting from the ascomata in a stellate fashion, unitunicate asci with an amyloid apical ring or ring lacking and ellipsoidal, ellipsoidal-fusiform or allantoid, hyaline, aseptate ascospores. Members of Iodosphaeria are infrequently found worldwide as saprobes on various hosts and a wide range of substrates. Only three species have been sequenced and included in phylogenetic analyses, but the type species, I. phyllophila, lacks sequence data. In order to stabilize the placement of the genus and family, an epitype for the type species was designated after obtaining ITS sequence data and conducting maximum likelihood and Bayesian phylogenetic analyses. Iodosphaeria foliicola occurring on overwintered Alnus sp. leaves is described as new. Five species in the genus form a well-supported monophyletic group, sister to the Pseudosporidesmiaceae in the Xylariales. Selenosporella-like and/or ceratosporium-like synasexual morphs were experimentally verified or found associated with ascomata of seven of the nine accepted species in the genus. Taxa included and excluded from Iodosphaeria are discussed.

Trapelia calyciformis sp. nov. from China

Trapelia calyciformis is described from China as a new species. The lichen is characterized by its gray-white thallus, zeorine apothecium with black disc and cracked excipulum, narrow paraphyses branched near the tip, 8-spored asci, aseptate ascospores with one vacuole, and the presence of gyrophoric acid. The specimens examined were deposited in LCUF. A key to the species of Trapelia reported in China is presented.

<p><strong><em>Kukwaea pubescens gen</em></strong><strong>. et<em> sp. nova </em>(Helotiales, incertae sedis), a new lichenicolous fungus on <em>Cetraria islandica</em>, and a key to the lichenicolous fungi occurring on <em>Cetraria </em>s. str.</strong></p>

A new lichenicolous genus Kukwaea is introduced for a species discovered on Cetraria islandica from coniferous forests in European and Asian parts of Russia. The new fungus is characterized by its cupulate, brown ascomata with grey to blackish disc surrounded by brownish grey hairs, exciple of textura angularis type, with crystals in the lower part, with granulose excipular hairs obtuse at the tips, simple to forked paraphyses, Calycina-type asci, and hyaline, aseptate ascospores. The DNA sequence data confirmed its placement in Helotiales, but the exact affiliation remains open. A worldwide key for lichenicolous fungi occurring on Cetraria s. str. is provided.

First Report of the Sexual Morph of Pseudofusicoccum adansoniae Pavlic, T.I.Burgess & M.J.Wingf. on Para Rubber

Pseudofusicoccum adansoniae Pavlic, T.I.Burgess & M.J.Wingf. and P. ardesiacum Pavlic, T.I.Burgess & M.J.Wingf. were collected from branches and twigs of Hevea brasiliensis Muell. Arg. in Phayao Province, northern Thailand. Pseudofusicoccum Mohali, Slippers & M.J.Wingf. is known only by its asexual morph. Here, we report the sexual morph of P. adansoniae based on phylogenetic analyses of a combined ITS, LSU, TEF1 and β-tubulin dataset. The sexual morph is characterized by immersed, uniloculate ascomata, cylindric-clavate asci with a long pedicel, a well-developed ocular chamber and short clavate, hyaline, aseptate ascospores, surrounded by a mucilaginous sheath. Descriptions, illustrations and molecular data are provided for the taxa.

Identification and pathogenicity of Cryphonectriaceae species associated with chestnut canker in China

Cryphonectriaceae species cause serious canker diseases on chestnut, oak and eucalypt trees. Recently, canker symptoms with typical orange fruiting bodies were observed on Chinese chestnut and oak trees in Hebei, Hubei, Shaanxi and Shandong Provinces in China. In the present study, isolates of these fungi were identified based on phylogenetic and morphological evidence, and their pathogenicities were tested on detached chestnut (Castanea mollissima) branches. DNA sequence comparisons of the internal transcribed spacer (ITS) regions and two regions of β‐tubulin (TUB1/TUB2) indicate that these isolates represent five species in the Cryphonectriaceae, viz. Cryphonectria japonica, Cryphonectria parasitica, Aurantiosacculus castaneae sp. nov., Cryphonectria neoparasitica sp. nov. and Endothia chinensis sp. nov. The sexual morph of Aurantiosacculus is discovered for the first time and can be distinguished from the other genera in Cryphonectriaceae by dark brown ascospores and tubiform appendages at both ends. Cryphonectria neoparasitica sp. nov. is different from the other Cryphonectria species by its aseptate ascospores. Endothia chinensis sp. nov. is the sole species in Endothia infecting the host genus Castanea. Additionally, it is much smaller than E. gyrosa and narrower than E. singularis in ascospores. The inoculation results showed that these five Cryphonectriaceae fungi isolated from chestnut or oak are all pathogenic to tested chestnut branches. Cryphonectria parasitica appears to be the most aggressive fungus, followed by C. neoparasitica sp. nov., C. japonica, E. chinensis sp. nov. and A. castaneae sp. nov.

Lichenicolous ascomycetes onSiphula-like lichens, with a key to the species

AbstractSixteen species of lichenicolous fungi are documented fromSiphula-like lichens. Two new genera based on new species are introduced.AmylogallaSuija, Motiej. & Kantvilas, characterized by I+ blue, K/I+ violet vegetative hyphae and ascomatal wall, immersed, cleistohymenial, yellowish to orange ascomata, unitunicate, non-amyloid, 8-spored asci and hyaline, ellipsoid, aseptate ascospores, is described fromParasiphulain Tasmania.SaaniaZhurb., characterized by superficial, stromatic, multilocular ascomata, non-amyloid hymenial gel, persistent periphysoids, bitunicate, non-amyloid, 4(–8)-spored asci and narrowly obovate to ellipsoid, 1(–3)-septate, initially hyaline and smooth-walled, later sometimes brown and verruculose ascospores, is described fromSiphulain South Africa. Four additional species are described as new: two fromSiphula(Cercidospora santessoniiMotiej., Zhurb., Suija & Kantvilas andStigmidium kashiwadaniiZhurb.) and two fromParasiphula(Endococcus hafellnerianusMotiej., Suija & Kantvilas andPyrenidium macrosporumMotiej., Zhurb., Suija & Kantvilas). Additional hosts and/or expanded geographical ranges are reported forAabaarnia siphulicola,Epigloea soleiformis, Plectocarpon gayanumandPyrenidium actinellum. The Southern Hemisphere is the centre of species richness for siphulicolous fungi, with 12 species restricted to this region. Taxa recorded for the Northern Hemisphere areSphaerellothecium siphulae(arctic and boreal) and the subcosmopolitanEpigloea soleiformisandPyrenidium actinellum, both of which are also known from various lichen hosts. The distribution of siphulicolous fungi strongly underpins the current generic classification ofSiphula-like lichens, with five species being confined exclusively toParasiphulaand nine toSiphula. A key to the taxa occurring onSiphulaandParasiphulais provided.

First Report of Tar Spot on Corn (Zea mays) Caused by Phyllachora maydis in Florida, Iowa, Michigan, and Wisconsin

Leaf lesions typical of those reported for tar spot of corn caused by Phyllachora maydis Maubl. were observed in commercial corn hybrids (Zea mays L.). In 2016, symptoms were observed in Jones County, IA, Palm Beach County, FL, Allegan County, MI, and in Green and Iowa counties, WI. In 2017, symptoms were observed again in Allegan County, MI, and in Grant and Lafayette counties, WI. Leaf signs and symptoms included ascomata, often surrounded by a narrow necrotic halo, on both healthy and senescent leaf material. Disease severity and incidence varied by location. Some fields had few infected plants (<1%), with some infected leaves only exhibiting a single ascoma, whereas in 2017 one field in Michigan had up to 90% infected plants with up to 80% disease severity on individual leaves. Morphological characteristics of the pathogen from all examined leaves from all locations were similar and consistent with the description of P. maydis (Parbery 1967). Ascomata, single or grouped with a clypeus, contained numerous paraphyses, with cylindrical asci containing hyaline, ellipsoid, aseptate ascospores 5.5 to 8 × 9.5 to 14 µm (n = 30). DNA was extracted from ascomata aseptically removed from leaves collected in each state. Voucher samples from each state were deposited in the U.S. National Fungus Collections (BPI). The internal transcribed spacer (ITS) regions of the ribosomal RNA gene were sequenced using primer pair ITS1F/ITS4A (Larena et al. 1999) for Iowa and Michigan samples and ITS4/ITS5 for Wisconsin (White et al. 1990). Sequences from Iowa, Michigan, and Wisconsin were identical and showed a 97% sequence homology to GenBank deposit accession KU184459.1, with a 90% query cover. A representative sequence from each state was deposited: Iowa (BPI 910561) GenBank MG881848, Michigan (BPI 910562) GenBank MG881847, and Wisconsin (BPI 910560) GenBank MG881846. Sequences were not obtained from the Florida sample (BPI 910568). Koch’s postulates were not performed given the obligate nature of the pathogen (Muller and Samuels 1984). This report documents the first confirmation of tar spot on corn in Iowa, Michigan, and Wisconsin (three states surrounding Indiana and Illinois, where it was first reported in 2015; Ruhl et al. 2016) and Florida. It has been reported in Central and South America that when coinfection of P. maydis and Monographella maydis occurs there can be significant yield loss. However, M. maydis has not yet been documented within the United States. There may currently be no significant losses in grain production; however, this disease could potentially affect silage corn production for which early dry-down is not desired, and it may increase lodging.

First Report of Tar Spot on Corn Caused by Phyllachora maydis in the United States

HomePlant DiseaseVol. 100, No. 7First Report of Tar Spot on Corn Caused by Phyllachora maydis in the United States PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Tar Spot on Corn Caused by Phyllachora maydis in the United StatesG. Ruhl, M. K. Romberg, S. Bissonnette, D. Plewa, T. Creswell, and K. A. WiseG. RuhlSearch for more papers by this author, M. K. RombergSearch for more papers by this author, S. BissonnetteSearch for more papers by this author, D. PlewaSearch for more papers by this author, T. CreswellSearch for more papers by this author, and K. A. WiseSearch for more papers by this authorAffiliationsAuthors and Affiliations G. Ruhl , Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47905 M. K. Romberg , Department of Agriculture-Animal Plant Health Inspection Service, Beltsville, MD 20705 S. Bissonnette D. Plewa , Department of Crop Sciences, University of Illinois, Urbana 61801 T. Creswell K. A. Wise , Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47905. Published Online:1 Apr 2016https://doi.org/10.1094/PDIS-12-15-1506-PDNAboutSectionsSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat In early September 2015, the Purdue Plant and Pest Diagnostic Lab (PPDL) received leaves of hybrid corn (Zea mays L.) from Carroll and Cass counties, Indiana, and Bureau, Dekalb, and LaSalle counties, Illinois, showing small (0.5 to 1.5 mm), black, circular, raised structures on the epidermis of leaves. The black structures were observed on both healthy and necrotic tissue and were surrounded by narrow tan halos. Disease severity varied across samples from a variety of commercial hybrids, ranging from 1 to 80% of leaf tissue affected. Microscopic observation revealed single and clustered ascomata within a clypeus, containing cylindrical unitunicate asci with ellipsoid, hyaline, uniserate, aseptate ascospores 6 to 8.5 × 11 to 14 µm (n = 25), and abundant filiform paraphyses. Based on these characters, the fungus was identified as Phyllachora maydis Maubl., cause of tar spot (Parbery 1967). Samples were sent to the USDA-APHIS in Beltsville, MD, for official confirmation, since the disease had not previously been reported in the United States. The fungus on samples from Indiana and Illinois was identified morphologically and officially confirmed on 9 September and 18 September 2015, respectively. These samples have been accessioned at the U.S. National Fungus Collections (BPI) in Beltsville, MD. DNA was extracted directly from ascomata on leaves using a Qiagen Plant Mini kit (Qiagen, Valencia, CA). Amplicons of the internal transcribed spacer regions were generated using standard methods with primers ITS4 and ITS5 for four samples of P. maydis; two from Indiana and two from Illinois. The sequence of the ITS region from the Carroll County sample (BPI 893231) was submitted to GenBank (Accession No. KU184459). Phyllachora maydis is classified as an obligate biotroph and is considered to be nonculturable (Muller and Samuels 1984). Multiple attempts to culture the fungus were unsuccessful. No P. maydis accessions previously existed in GenBank, and since Phyllachora spp. have primarily been identified by morphology, very few sequences of any species on any host exist in GenBank for comparison. To ensure the submitted P. maydis sequence is indeed a representative sequence of this fungus, it was compared and determined to be identical across the length sequenced to the sequence from a completely different P. maydis sample. After the initial confirmation, the disease was reported in five additional counties in Indiana, and 10 additional counties in Illinois. Tar spot is prevalent in Mexico and areas of Central and South America (Hock et al. 1992). Phyllachora maydis alone is not known to cause economic damage in these areas, but the presence of P. maydis with another fungus, Monographella maydis, can result in severe disease (Hock et al. 1995). Monographella maydis was not detected morphologically in any of the U.S. samples, and no associated yield loss was observed in fields in Indiana and Illinois with the disease. The economic importance of the disease in the United States is still unknown at this time since symptoms were observed too late in the season to affect yield. Phyllachora maydis is not known to infect seed. It is suspected that inoculum may have been transported to the United States via weather events originating in Central America or Mexico.

Rhagadolobiopsis, a new genus of Parmulariaceae from Brazil with a description of the ontogeny of its ascomata

During a survey of the mycobiota of selected Brazilian ferns we discovered a new genus of Parmulariaceae causing tar spot-like symptoms on leaves of Thelypteris serrata (Thelypteridaceae). The new genus and species, decribed as Rhagadolobiopsis thelypteridis, differs from morphologically similar species of Rhagadolobium in possessing colorless, aseptate ascospores and a hymenial gel that does not become blue with iodine. In addition this is the first record of a fungus on T. serrata, and the first Parmulariaceae recorded on a member of the Thelypteridaceae. The ontogeny of the ascomata is described and illustrated here for the first time for the Parmulariaceae.

A new species of the lenticel fungal genus Claviradulomyces (Ostropales) from the Brazilian Atlantic forest tree Xylopia sericea (Annonaceae)

Claviradulomyces xylopiae sp. nov. is introduced for a fungus occurring in association with abnormal (enlarged, spongy) lenticels of Xylopia sericea (Annonaceae), a common tree of the Atlantic forest and Cerrado ecosystems in Brazil. This is the second species described in the genus and, although it is morphologically distinct from the type species, C. dabeicola from West Africa, it possesses the same characteristics. Apothecial ascomata have periphysoids and paraphyses that are inflated apically (clavate), and ornamented with denticles (raduliform). Furthermore, similar to the type species, it also has long-cylindric or acerose, aseptate ascospores and conidia. An additional asexual morph was produced in culture and is described. Molecular studies of C. dabeicola and the new species confirmed a placement in Ostropales, although a relationship to Odontotremataceae was not supported. Both species were consistently in association with abnormal lenticular development on their woody hosts. It remains to be ascertained, however, if these are the causal agents of the bark disorders, or, simply, opportunistic colonisers. The finding of the second species in the genus Claviradulomyces on a plant from a distantly related family to that of the host of C. dabeicola (Erythroxylaceae) for the genus on a different continent suggests that fungi in this genus may be common on lenticels of other woody plants, and could even have a pantropical distribution. It is possible that fungi in the genus have remained unreported until now because lenticels have remained neglected as a habitat surveyed by mycologists.

A monograph of Allantonectria, Nectria, and Pleonectria (Nectriaceae, Hypocreales, Ascomycota) and their pycnidial, sporodochial, and synnematous anamorphs

Although Nectria is the type genus of Nectriaceae (Hypocreales, Sordariomycetes, Pezizomycotina, Ascomycota), the systematics of the teleomorphic and anamorphic state of Nectria sensu Rossman has not been studied in detail. The objectives of this study are to 1) provide a phylogenetic overview to determine if species of Nectria with Gyrostroma, Tubercularia, and Zythiostroma anamorphs form a monophyletic group; 2) define Nectria, segregate genera, and their species using morphologically informative characters of teleomorphic and anamorphic states; and 3) provide descriptions and illustrations of these genera and species. To accomplish these objectives, results of phylogenetic analyses of DNA sequence data from six loci (act, ITS, LSU, rpb1, tef1 and tub), were integrated with morphological characterisations of anamorphs and teleomorphs. Results from the phylogenetic analyses demonstrate that species previously regarded as the genus Nectria having Gyrostroma, Tubercularia, and Zythiostroma anamorphs belong in two major paraphyletic clades. The first major clade regarded as the genus Pleonectria contains 26 species with ascoconidia produced by ascospores in asci, perithecial walls having bright yellow scurf, and immersed or superficial pycnidial anamorphs (Zythiostroma = Gyrostroma). A lineage basal to the Pleonectria clade includes Nectria miltina having very small, aseptate ascospores, and trichoderma-like conidiophores and occurring on monocotyledonous plants. These characteristics are unusual in Pleonectria, thus we recognise the monotypic genus Allantonectria with Allantonectria miltina. The second major clade comprises the genus Nectria sensu stricto including the type species, N. cinnabarina, and 28 additional species. Within the genus Nectria, four subclades exist. One subclade includes species with sporodochial anamorphs and another with synnematous anamorphs. The other two paraphyletic subclades include species that produce abundant stromata in which the large perithecia are immersed, large ascospores, and peculiar anamorphs that form pycnidia or sporodochia either on their natural substrate or in culture. In this study the evolution of species, morphology, and ecology of the three genera, Allantonectria, Nectria, and Pleonectria, are discussed based on the phylogenetic analyses. In addition, descriptions, illustrations, and keys for identification are presented for the 56 species in Allantonectria, Nectria, and Pleonectria.Taxonomic novelties:New species: Nectria argentinensis Hirooka, Rossman & P. Chaverri, Nectria berberidicola Hirooka, Lechat, Rossman, & P. Chaverri, Nectria himalayensis Hirooka, Rossman, & P. Chaverri, Nectria magnispora Hirooka, Rossman, & P. Chaverri, Nectria mariae Hirooka, Fournier, Lechat, Rossman, & P. Chaverri, Nectria pyriformis Hirooka, Rossman & P. Chaverri, Pleonectria boothii Hirooka, Rossman & Chaverri, Pleonectria clavatispora Hirooka, Rossman & P. Chaverri, Pleonectria ilicicola Hirooka, Rossman & P. Chaverri, Pleonectria okinawensis Hirooka, Rossman & P. Chaverri, Pleonectria pseudomissouriensis Hirooka, Rossman & P. Chaverri, Pleonectria quercicola Hirooka, Checa, Areual, Rossman & P. Chaverri, Pleonectria strobi Hirooka, Rossman & P. Chaverri. New combinations: Cosmospora proteae (Marinc., M.J. Wingf. & Crous) Hirooka, Rossman & P. Chaverri, Nectricladiella viticola (Berk. & M.A. Curtis) Hirooka, Rossman & P. Chaverri, Neocosmospora guarapiensis (Speg.) Hirooka, Samuels, Rossman & P. Chaverri, Neocosmospora rehmiana (Kirschstein) Hirooka, Samuels, Rossman & P. Chaverri, Pleonectria aquifolii (Fr.) Hirooka, Rossman & P. Chaverri, Pleonectria aurigera (Berk. & Rav.) Hirooka, Rossman & P. Chaverri, Pleonectria chlorinella (Cooke) Hirooka, Rossman & P. Chaverri, Pleonectria coryli (Fuckel) Hirooka, Rossman & P. Chaverri, Pleonectria cucurbitula (Tode: Fr.) Hirooka, Rossman & P. Chaverri, Pleonectria lonicerae (Seeler) Hirooka, Rossman & P. Chaverri, Pleonectria rosellinii (Carestia) Hirooka, Rossman & P. Chaverri, Pleonectria rubicarpa (Cooke) Hirooka, Rossman & P. Chaverri, Pleonectria sinopica (Fr.: Fr.) Hirooka, Rossman & P. Chaverri, Pleonectria sphaerospora (Ellis & Everh) Hirooka, Rossman & P. Chaverri, Pleonectria virens (Harkn.) Hirooka, Rossman & P. Chaverri, Pleonectria zanthoxyli (Peck) Hirooka, Rossman & P. Chaverri.

Resolving the phylogenetic and taxonomic status of dark-spored teleomorph genera in the Botryosphaeriaceae

Species in the Botryosphaeriaceae are common plant pathogens and saprobes found on a variety of mainly woody hosts. Teleomorphs typically have hyaline, aseptate ascospores. However, some have been reported with brown ascospores and their taxonomic status is uncertain. A multi-gene approach (SSU, ITS, LSU, EF1-alpha and beta-tubulin) was used to resolve the correct phylogenetic position of the dark-spored 'Botryosphaeria' teleomorphs and related asexual species. Neodeightonia and Phaeobotryon are reinstated for species with brown ascospores that are either 1-septate (Neodeightonia) or 2-septate (Phaeobotryon). Phaeobotryosphaeria is reinstated for species with brown, aseptate ascospores that bear an apiculus at either end. The status of Sphaeropsis is clarified and shown to be the anamorph of Phaeobotryosphaeria. Two new genera, namely Barriopsis for species having brown, aseptate ascospores without apiculi and Spencermartinsia for species having brown, 1-septate ascospores with an apiculus at either end are introduced. Species of Dothiorella have brown, 1-septate ascospores and differ from Spencermartinsia in the absence of apiculi. These six genera can also be distinguished from one another based on morphological characters of their anamorphs. Although previously placed in the Botryosphaeriaceae, Dothidotthia, was shown to belong in the Pleosporales, and the new family Dothidotthiaceae is introduced to accommodate it.

Freshwater ascomycetes: Aquapoterium pinicola, a new genus and species of Helotiales (Leotiomycetes) from Florida

As part of a survey of freshwater ascomycetes in Florida an unusual discomycete fungus belonging in the Helotiales was found on submerged Pinus needles. This fungus is described and illustrated as a new genus and species, Aquapoterium pinicola, based on morphological data. Aquapoterium pinicola is characterized by minute, hyaline apothecia with an excipulum one cell layer thick of parallel hyphae composed of chains of cells narrow at the basal end and enlarged at the apical end and aseptate ascospores that are surrounded by a gelatinous sheath. Analyses of the nuclear ribosomal large subunit DNA sequence data confirmed its placement within the Helotiales but failed to resolve its familial placement.

Freshwater ascomycetes: Aquapoterium pinicola, a new genus and species of Helotiales (Leotiomycetes) from Florida

As part of a survey of freshwater ascomycetes in Florida an unusual discomycete fungus belonging in the Helotiales was found on submerged Pinus needles. This fungus is described and illustrated as a new genus and species, Aquapoterium pinicola, based on morphological data. Aquapoterium pinicola is characterized by minute, hyaline apothecia with an excipulum one cell layer thick of parallel hyphae composed of chains of cells narrow at the basal end and enlarged at the apical end and aseptate ascospores that are surrounded by a gelatinous sheath. Analyses of the nuclear ribosomal large subunit DNA sequence data confirmed its placement within the Helotiales but failed to resolve its familial placement.

A SYNOPSIS OF THE GENERA SKYTTEA, LLIMONIELLA AND RHYMBOCARPUS (LICHENICOLOUS ASCOMYCOTA, LEOTIALES)

Abstract: The genus Skyttea is characterized by urceolate ascomata, with a narrow pore when young, a greenish or brownish, rarely reddish exciple of conglutinate hyphae with subglobose to ±cylindrical lumina, bordered near the margin by hyaline to greenish or brownish, usually smooth, straight hairs, the absence of periphyses, rarely branched and apically hardly thickened paraphyses, asci and a hymenium that are entirely I− and KI−, a thin lateral and a very thick apical ascus wall with a small ocular chamber, and normally aseptate ascospores. It is considered to belong to the Leotiales and not to the Ostropales. It comprises at least 17 species, including S. caesii sp. nov., S. carboneae sp. nov., S. lecanorae sp. nov., S. mayrhoferi sp. nov., S. pyrenulae sp. nov., S. radiatilis comb. nov., S. tavaresae sp. nov. and S. thelotrematis sp. nov. Rhymbocarpus is shown to be a distinct leotialean genus, distinguished from Llimoniella by a different excipular structure, different pigments and the presence of excipular hairs, which, in some species, are embedded in the excipular gel and thus not visible macroscopically. In addition to the type species, R. geographici, of which a neotype is designated, it includes R. boomii sp. nov., R. cruciatus comb. nov., R. fuscoatrae comb. nov., R. makarovae sp. nov., R. neglectus comb. nov.,R. pertusariae sp. nov., R. pubescens comb. nov. and R. stereocaulorum comb. nov. Llimoniella s. str. comprises at least 6 species, including the type, L. scabridula, L. adnata, L. pertusariae sp. nov., L. pyrenulae sp. nov., L. ramalinae comb. nov. and L. vinosa comb. nov. Several species formerly assigned to Skyttea or Llimoniella are now included in the leotialean genus Unguiculariopsis, and the following new combinations are proposed: Unguiculariopsis acrocordiae comb. nov., U. groenlandiae comb. nov. andU. lesdainii comb. nov. A lectotype is chosen for Lichen stictoceros, which is shown to be a synonym ofEvernia prunastri . Keys are given for the species of Skyttea, Llimoniella and Rhymbocarpus, and for the lichenicolous genera of Leotiales and Ostropales.

Cannonia gen. nov., from palms in the Southern Hemisphere

Cannonia gen. nov. is introduced to accommodate three collections of an unusual taxon, originally described as Ceratostoma australe. Cannonia is thought to be xylariaceous, due to its globose immersed ascomata with the stroma reduced to a clypeus, well-developed paraphyses, unitunicate asci lacking an apical apparatus, and dark brown, aseptate ascospores with a germ slit. Cannonia is compared with other possibly related genera and illustrated with interference contrast micrographs.

A Taxonomic Revision of the Genus Endoxyla

The pyrenomycete genus Endoxyla (Ascomycotina, Clypeosphaeriaceae) is revised based on the examination of type and authentic material. Five species, E. macrostoma, E. munkii sp. nov., E. operculata, E. parallela and E. xanthostroma sp. nov., are included and a key to the species is given. Endoxyla macrostoma is designated as holotype. Sixteen species and one variety are excluded from Endoxyla and three species are treated as doubtful. The synonymy of Ceratostomella with Endoxyla is rejected and a new combination Ceratostomella hyalostoma is proposed. The taxonomic position of Endoxyla is discussed. The genus Endoxyla was established by Fuckel (1871) for stromatic species possessing immersed ascomata with stout, apically thickened necks, clavate asci, dark, aseptate ascospores and abundant, filiform paraphyses. He referred three species to the genus; Endoxyla macrostoma Fuckel, Sphaeria parallela Fr. and S. operculata Alb. & Schw. Saccardo (1882) formally combined the latter two species in Endoxyla and described the ascospores of E. parallela as aseptate. He included the genus in the section Allantosporae of the Sphaeriaceae, an artificial assemblage of pyrenomycetes characterized by their allantoid ascospores. Winter (1886) treated Endoxyla as a subgenus of Valsa Fr., which he placed in the Valseae. Ellis and Everhart (1892, 1894) maintained Endoxyla as a separate genus in this family and accepted E. macrostoma with aseptate ascospores, E. parallela with uniseptate ascospores, and four species with phragmosporous ascospores including E. fraxini (Ell. & Ev.) Ell. & Ev. Berlese (1902, 1905) included only species with aseptate ascospores in Endoxyla and transferred E. parallela to Endoxylina Romell. He considered Endoxyla to be related to Cryptosphaeria Grev. Von Hohnel (1915) removed the genus from the Valseae and treated Endoxyla as a subgenus