Distribution and ecology of myxomycetes in the high-elevation oak forests of Cerro Bellavista, Costa Rica

Myxomycetes associated with a high-elevation (.3000 m) oak forest in the Talamanca Range of Costa Rica were studied for 7 mo. Field collections were supplemented with collections obtained from moist chamber cultures prepared with samples of bark and ground litter of Quercus costaricensis. Various microenvironmental parameters including pH, substrate moisture and diameter, height above the ground and canopy openness were recorded for each field collection, whereas macroenvironmental data for temperature and precipitation were obtained from a meteorological station near the study area. Niche breadth and niche overlap indices were calculated to assess possible resource partitioning by myxomycetes. Thirty-seven species were recorded, including 11 new records for Costa Rica, eight for Central America and one for the neotropics. Both PCA and NMS multivariate analyses indicated that pH and height above the ground explained most of the observed variation, although substrate diameter also seemed to be an important factor. Precipitation showed an inverse correlation with the number of fruitings, confirming its importance as a macroenvironmental factor. Niche overlap values were not higher for closely related species and values for niche breadths were similar for most of the more common species, suggesting that most members of the assemblage of myxomycetes present in the study site are ecological generalists.National Science Foundation/[DEB-0316284]/NSF/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ingeniería::Instituto Investigaciones en Ingeniería (INII

A review of the Costa Rican myxomycetes (Amebozoa)

There has not been a comprehensive review of the taxonomic composition of the assemblage of myxomycetes known from Costa Rica since 1975. As a result of a series of studies carried out in the country during the last decade, considerable additional data now exist, and the review presented herein provides an update on this group of organisms. Collecting carried out in Costa Rica since 1975, a review of the published literature, and an examination of herbarium specimens were used to generate an annotated list consisting of a total of 208 species in 36 different genera. This includes 62 species not previously reported from Costa Rica. The relative abundance of the different orders follows the expected distribution for the Neotropics, with the order Physarales being the most abundant. Interestingly, the data also show that the distribution of species is highly heterogenous. This result suggests that most myxomycetes in Costa Rica are highly specialized for certain microhabitats defined by macro- and microenvironmental factors.Desde 1975 no se ha llevado a cabo una revisión exhaustiva de la composición taxonómica de los mixomicetes de Costa Rica. Como resultado de una serie de proyectos de investigación que se han desarrollado durante la última década, nueva información se encuentra disponible y es por ello que la presente revisión se considera como una actualización sobre este grupo de organismos para este país. El material recolectado desde 1975, una profunda revisión bibliográfica y el examen de especímenes de herbario fueron usados para generar una lista de 208 especies pertenecientes a 36 géneros diferentes. Esta lista incluye 62 especies no comunicadas anteriormente para Costa Rica. La abundancia relativa de los diferentes órdenes concuerda con la distribución esperada para el Neotrópico, siendo el orden Physarales el más abundante. De forma interesante, los datos también muestran que la distribución de las especies es altamente heterogénea. Este resultado sugiere que la mayoría de los mixomicetes en Costa Rica están altamente especializados alrededor de microhabitats definidos por factores macro y microambientales.Ministerio del Ambiente y Energía/[]/MINAE/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Myxomycetes associated with pipevine, a temperate liana

Coelho IL, Stephenson SL 2012 -Myxomycetes associated with pipevine, a temperate liana. Mycosphere 3(2), 245-249, Doi 10.5943 /mycosphere/3/2/8 Pinevine (Aristolochia macrophylla Lam.), a climbing woody vine native to temperate forests of eastern North America, is morphologically similar to many of the lianas characteristic of moist tropical forests. In August 2010, samples of dead pinevine collected from a study site in the Great Smoky Mountains National Park were used to prepare a series of 50 moist chamber cultures. Thirtyseven of the 50 cultures (74%) yielded evidence (either plasmodia or fruiting bodies) of myxomycetes. Fourteen species representing seven genera were recorded, with members of the Trichiales (41% of all records) and Physarales (49% of all records) the most abundant

New additions to the myxobiota of Peru

Recent efforts to study myxomycetes in many areas of the world have resulted in a considerable increase in the number and quality of regional species lists, especially during the last decade. However, in South America certain countries such as Peru continue to be highly understudied with respect to this group of organisms. During a series of surveys carried out in 2007 in several different areas of Peru, 49 species of myxomycetes not previously known for this country were recorded. Basic ecological information was also collected and analyzed in the context of available data on myxomycetes for the Neotropics. With the new species reported herein, the myxobiota of Peru is increased to 80 species, which is still a low number when the natural and biogeographical characteristics of Peruvian landscapes are considered.Amazon Conservation Association/[]//Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ingeniería::Instituto Investigaciones en Ingeniería (INII)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Phenology of myxomycetes in Turrialba, Costa Rica

Long-term monitoring and phenological patterns of microbial communities are rare in the scientific literature. Myxomycetes have life cycle characteristics that allow both to be documented. The present study summarizes the integrated floristic and bioclimatic components of a 30-month assessment of myxomycete sporocarps in a premontane tropical forest in Turrialba, Costa Rica. Based on monthly visits and a standard sampling effort of 120 minutes per visit, myxomycetes were recorded on leaves, twigs, and logs on the ground by two to three people in 20-minute periods associated with six different collecting sites within a 34-hectare successional forest patch. Biological data were analyzed using three recorded climatic variables obtained in situ during the complete period of study. Also, the Oceanic Niño Index (ONI), provided by NOAA, an estimate of El Niño-Southern Oscillation (ENSO), was evaluated in the analyses. Overall, 54 species and 2245 records of myxomycetes were recorded, with an average of 14.5 species (range between 6-24) and 78.4 records (range between 20-110) detected each month. In general, neither the number of records nor the number of species were associated with individual climate variables, but multiple regression analyses showed that a combination of the accumulated precipitation of the four days before sampling and the average relative humidity can explain most of the fruiting dynamics (R2 = 0.56). When the ONI index was included in the analyses, the explained variability increased (R2 = 0.64), and when a categorization of months based on the same index was used, analyses showed that both the number of records and species evenness were affected by ENSO. At the species level, Hemitrichia calyculata was the only species observed during every month, closely followed by Arcyria cinerea, A. denudata, and Physarum compressum, recorded on most visits. Sporadic fruiting in some species such as Tubifera microsperma, P. tenerum, P. bogoriense, P. melleum, and Metatrichia vesparia could have been associated with local climate oscillations influenced by ENSO patterns. Phenological patterns were observed at the species level, indicating that in the Neotropics, under favorable conditions, myxomycete sporocarps are practically always present, but species assemblages vary temporally. These variations are primarily driven by local climate, but regional climate dynamics also affect fruiting patterns. Presumably, the remaining ecological effect on fruiting patterns in the Neotropics can be attributed to certain finer factors such as ecosystem structure, substrate quality/ availability, and biotic interactions. As such, phenomena such as climate change can have an important effect on the production of sporocarps by tropical myxomycetes, with subsequent effects of their ecological dynamics.Universidad de Costa Rica/[570-B8-006]/UCR/Costa RicaUCR::Sedes Regionales::Sede del Atlántico::Recinto de Paraíso::Finca Experimental Interdisciplinaria de Modelos Agroecológicos (FEIMA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ingeniería::Instituto Investigaciones en Ingeniería (INII

Ecology of Soil Eumycetozoans

Eumycetozoans, commonly referred to as slime moulds, are common to abundant organisms in soils. Three groups of slime moulds (myxogastrids, dictyostelids and protostelids) are recognized, and the first two of these are among the most important bacterivores in the soil microhabitat. The purpose of this paper is first to provide a brief description of all three groups and then to review what is known about their distribution and ecology in soils

Assemblages of myxomycetes associated with three different substrates affected by forest wildfires

Background and aims – In late November and early December of 2016, forest wildfires occurred over portions of the Great Smoky Mountains National Park (USA) and more than 4 000 ha were affected. Previous studies have shown that myxomycete assemblages can be greatly impacted as a result of this type of disturbance; after which, the recovery of the forest determines the availability of substrates for new colonisation. The objective of the project reported herein was to assess the impact of wildfires on the recovery of the assemblages of myxomycetes associated with three different substrates (forest floor leaf litter, the bark of living trees, and woody twigs) in two areas with different fire intensity. Material and methods – Two study areas subjected to different fire intensity were selected and sampled 30 months after the wildfires. Myxomycetes were studied using the moist chamber culture technique as it applies to these organisms. Satellite imagery was used to determine forest recovery and similarity indices were used to compare experimental myxomycete assemblages among study areas and substrates. Historical data were used as a reference to contextualise the results. Key results – A total of 38 species of myxomycetes representing 17 different genera were recorded from the two study areas. Samples from the lower intensity burn area yielded more myxomycetes than samples from the higher intensity burn area, with values of 84% and 59%, respectively. This same pattern was also observed for the number of recorded specimens (133 and 93, respectively). The comparison of experimental assemblages with previous data suggested that ground litter assemblages were still in early stages of recovery, whereas the assemblages associated with bark and twigs had recovered much faster. Conclusion – The relatively higher intensity fire had more of an effect on myxomycetes than the relatively lower intensity fire. Myxomycete assemblages are resilient to wildfires and they recover differentially depending on the substrate they grow on.Slime Mold Project at the University of ArkansasDiscover Life in AmericaUniversidad de Costa Rica /[731-B7-721]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ingeniería::Instituto Investigaciones en Ingeniería (INII)UCR::Vicerrectoría de Docencia::Ingeniería::Facultad de Ingeniería::Escuela de Ingeniería de Biosistema

The effect of wildfires on wood-decay fungi in the Great Smoky Mountains National Park

Background: In late November and early December of 2019, wildfires occurred over portions of the Great Smoky Mountains National Park. More than 4,000 ha were affected by the wildfires. The objective of the research reported herein was to access the impact of these wildfires on the assemblages of wood-decay fungi associated with the study areas in the park.Methods: The investigated fungi were confined to two study areas; the first subjected to a relatively high intensity burn and the second subjected to a relatively low intensity burn. In addition to specimens of fungi obtained in the field, small pieces of coarse woody debris were assembled, brought back to the laboratory and placed in plastic chambers for incubation and kept moist. Over the course of two months, fruiting bodies appearing in these incubation chambers were observed and collected. All specimens from both the field and incubation chambers were identified from sequences of the internal transcribed spacer (ITS) region of the ribosomal DNA.Results: A total of 31 different taxa were identified along with nine taxa reported previously as unknown and uncultured. However, almost all of these records were from the study area subjected to the relatively low intensity burn.Conclusion: The relatively high intensity burn site was almost completely devoid of wood-decay fungi.Keywords: Great Smoky Mountains National Park; ITS ribosomal DNA region; Wood-decay fung