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Featured Fungus Number 41

Nemania serpens var. hydnicola
A fungicolous fungus

Fungi can grow on almost everything, including other fungi. Those that do are called "fungicolous fungi." The photo shows stromata of the xylariaceous Ascomycete Nemania serpens var. hydnicola (Schwein.) Y.-M. Ju and J.D. Rogers, fruiting on the hymenial surface of a detached, rotting Fomitopsis pinicola (Sw.:Fr.) P. Karst. conk collected near Victoria, British Columbia, Canada.  Nemania serpens var. hydnicola differs from the typical variety in that its ascus rings are amyloid, the ascospores have abruptly narrowed or "pinched" ends, and it is frequently fungicolous on Fomitopsis pinicola. Collection records from North America are rare to date, possibly due to the cryptic habit and preferred substrate of this fungus. For more information on N. serpens var. hydnicola, including the unusual ability of an isolate to fruit in culture, click on the accompanying photo. [file size:  675 kb]

 

Featured Fungus Number 42

Myrothecium roridum
A newly discovered endophyte of Whitebark Pine (Pinus albicaoulis)

The asexual fungus Myrothecium roridum is a rather mysterious organism, pathogenic on cotton plants in India, coffee plants in Guatemala, as other hosts on which it produces leaf spots, cankers, or rots. Endophytic isolates of M. roridum can produce biologically active trichothecenes with potential for activity against important plant pathogens such as the rice blast fungus, Pyricularia oryzae and Sclerotinia sclerotiorum. Although reported from some 263 host species representing 119 genera, until very recently all known hosts were angiosperms. Recently M. roridum was isolated from Whitebark pine (Pinus albicaoulis ) in Oregon, the first time it has been found growing in a gymnosperm. Because of its ability to produce metabolites that impede growth of other fungi, it is possible that M. roridum may have a role in combating Cronartium ribicola, the cause of white pine blister rust, one of the most damaging plant pathogens introduced by people into North America. For more information click on the accompanying photograph of hyphae produced by M. roridum in culture. [file size:  508 kb]

 

Featured Fungus Number 43

Lecidea ramulosa
A new lichen species from the Bering Sea region

Lecidea ramulosa is an unusual, minutely fruticose species in this normally crustose genus. Note the black apothecium, the terete white branching thallus, and a possible dark parasitic fungus. This lichen, along with many other lichenized fungi, contributes to high biodiversity in Noatak National Preserve, Alaska. This lichen was featured in a recent study focused on macrolichen diversity that also included numerous reports of microlichens. A total of 364 taxa were reported. The 88 0.38-ha plots included in the study averaged 26 species of macrolichens, while the best estimate of the true average was 42 species per plot. The raw estimate of gamma diversity (park-wide macrolichen species richness) was 209 species, with jackknife estimates adjusting this to 255 or 290 species, depending on the estimator. Overall beta diversity was rather high at 7.1, reflecting the considerable variation in lichen communities among topographic positions, rock chemistry, substrate pH, climate, and vegetation. To learn more about the diversity of lichens in Noatak Preserve, along with comparisons to Bering Land Bridge Preserve, click on the accompanying illustration [file size: 408 kb].

 

Featured Fungus Number 44

Poroleprieuria rogersii
A strange, saprobic fungus from the tropics

Poroleprieuria rogersii is an unusual tropical pyrenomycete found growing on dead wood. It produces small vertical, cylindrical, carbonaceous stromata with perithecia embedded in the apices. Perithecia contain cylindrical asci with brown, one-celled, inaequilateral ascospores that are expelled through ostioles at the stromatal tips. Superficially the fungus resembles species of Leprieuria, but it differs from that genus in forming ascospores with germ pores instead of germ slits. For this reason the fungus was placed in the new genus Poroleprieuria, as Poroleprieuria rogersii. The species was named in honor of Professor Jack D. Rogers of Washington State University, who has devoted his career to the study of xylariaceous fungi. The fungus is known only from the State of Puebla in south-central Mexico. For more information about Mexican Ascomycetes, click on the accompanying photograph that shows two distinctive stromata (approximately 7 mm high) characteristic of P. rogersii. [file size: 274 kb].

 

Featured Fungus Number 45

Xylaria griseo-olivacea
A rare fungus of neotropical cloud forests and wet lowland forests

I thought little Martians had landed when Sharon Matola brought in the Xylaria griseo-olivacea J.D. Rogers & Rossman pictured here. We were collecting fungi in a cloud forest on the highest peak in Belize in Central America known as Doyle's Delight. The peak's name refers to Arthur Connan Doyle's book about a lost world on an isolated tepui in Venezuela that was subsequently featured in the movie ‘Up'. The cloud forest we explored in Belize was of special interest to us as it and neighboring peaks have remained above sea level since the Cretaceous-Tertiary boundary, and may thus harbor relic species. A number of species found at Doyle's Delight were known previously only from Amazonia, including X. griseo-olivacea . This unusual, species of Xylaria with green globose-stipitate stromata is known from only a few collections in Venezuela and Ecuador. It was originally described by Rogers et al. in a paper on the fungi of Cerro de Neblina – a cloud-covered tepui in Venezuela, but the type collection was actually made at a lowland Amazonian airport near the base camp for their expedition. While X. griseo-olivaceae did not turn out to be a cloud forest endemic at potential risk of extinction for cloud base lifting associated with regional and global climate change, it and X. platypoda (another rare Amazonian species with a disjunct distribution) served as the impetus to answer this question. Several other species of Xylaria were found to be restricted to cloud forests and high elevations in the Neotropics. [Contributed by D. Jean Lodge.] For more information about montane and cloud forest specialists among Neotropical Xylaria, click on the accompanying photograph of X. griseo-olivacea. [file size: 225 kb].

 

Featured Fungus Number 46

Armillaria solidipes
A common root-rotting fungus attacking conifers in North America

Armillaria solidipes, pictured at left, is a common mushroom fungus that causes a root-rot disease across the northern United States and throughout Canada's conifer forests. The species has been known as A. ostoyae since 1970 but recent studies demonstrated that C.H Peck named this species A. solidipes in 1900, seventy years before the name A. ostoyae was coined. Thus, A. solidipes is the name that is proper for this species. Such name changes, even for common and economically important fungi, are made frequently because we are in the early stages of understanding the biology and classification of fungi. The considerations leading to the use of Peck's name for this species can be found in the article by Burdsall and Volk, which can be accessed by clicking on the photo at the left. [file size: 467 kb]

 

Featured Fungus Number 47

Dendrothele gilbertsonii
A recently described new species from southern Arizona

The genus Dendrothele includes several dozen species of Basidiomycetes that produce reduced fruiting bodies (known as basidiomes) on substrates such as tree bark. Macroscopically, a Dendrothele basidiome could be mistaken for a splash of dried paint, but microscopically the basidiomes reveal themselves to be composed of complex tangles of specialized hyphae and basidia. Analyses of DNA sequences indicate that the genus is polyphyletic, suggesting that strong selection pressures have favored the simplification of basidium-producing structures in a variety of lineages. The species Dendrothele gilbertsonii was based on specimens collected from Quercus arizonica at a single location in southern Arizona. One can only speculate about the geographical distribution of this species—is it truly restricted to one site or would additional collecting determine it to have a wider distribution? Providing a clear description of the species gives mycologists information they need to address this and other mysterious aspects of the biology of this fungus. Click on the accompanying photograph of a basidiome of this species (scale bar = 3 mm) to see the article by Nakasone on this and other species of Dendrothele. [file size: 1673 kb]

 

Featured Fungus Number 48

Leightoniomyces phillipsii
A soil-dwelling fungus recently found for the first time in North America

It is a truism in mycology that the known geographical ranges of fungi tend to mirror the distributions of scientists who know how to find them. The fungus Leightoniomyces phillipsii has been known for some time to occur in the British Isles and the Azores. Recently it was found near the town of Tenmile, Oregon, its first known occurrence in North America. The tiny fruiting bodies, called synnemata, could be seen only with a hand lens; perhaps their small size contributed to the fungus being overlooked by other workers. Although the Oregon fungus was found growing on soil, previous reports suggested that L. phillipsii can be lichenicolous (growing on lichens), and a report from 1875 indicated that it is muscicolous (growing on mosses). Now that it has been documented and described in North America, research is possible on other aspects of its biology, such as how it interacts with other organisms in the soil. For information on this newly recognized member of North America's mycota, click on the accompanying photograph of synnemata of L. phillipsii to read the article by McCune and Stone. [file size: 1325 kb]