Large Spores Research Articles

Micromorphology of fern spores as a tool in taxonomy of East-Central European species from the family Aspleniaceae (Polypodiopsida)

The family Aspleniaceae consists of ca. 730 fern species found primarily in the tropics but present also in the temperate zone. Recently, researchers have been increasingly interested in spore morphology, as it provides valuable information used in taxonomic and phylogenetic analyses. This study aimed to (1) describe in detail spore morphology in species of the family Aspleniaceae from Central and Eastern Europe; (2) attempt to use their features in taxonomic analyses; and (3) create a key to species identification on the basis of spores. e study was based on <i>Asplenium</i> spores of 10 species from 57 localities. The morphological type of spores was very similar in all the studied species, whereas spore microsculpture varied widely between and within species. This makes it difficult to use spores for species identification. Nevertheless, spore morphology allows the identification of six species, while the others form groups composed of 2–3 species each. In the group consisting of <i>A. adulterinum</i>, <i>A. trichomanes</i>, and <i>A. ruta-muraria</i>, the last species is distinguished by larger spore size (more than 50 μm long).

Burning Frequency Influences Plant Composition and Diversity and Mycorrhizal Spore Density in a Lateritic Dry Deciduous Sal Dominated Forest

Abstract: Burning in forest floor, specially, in deciduous forests is an annual practice of forest dwellers in some states of India to collect non timber forest produce at ease. Sometimes this springtime burning get out of control and damage the forest severely. Sal dominated mixed forest in Godapyasal range, Midnapore division, West Midnapore in south West Bengal, with different fire incidence histories was taken for the study. An intensive survey of sites with regular burning, occasional burning and no burning were done to study plant diversity and community composition and the results were compared within different sites. Severe burning regimes damaged the plant density drastically rendering the saplings of subdominants only near ground level as coppice. Mild fire frequencies, though not severely damaged plant community, differed from unburned area significantly. Fire hardy tree species are dominant and subdominant in both sites. In severe burned site, plant diversity increased with a number of invasive perennials and annuals and spiny undershrubs and show even distribution. Common plants in the three communities were observed to be affected in their community parameters with burning frequency. Frequent and occasional burning both reduced mycorrhizal population with larger spores drastically and not replaced even after nine months of burning. AMF with smaller spores are less affected.

Hysterium madraspatanum (Hysteriaceae), a new species from Tropical Dry Evergreen Forest of Tamil Nadu, India

A new species of Hysterium, is described from tropical dry evergreen forest region of Chennai, Tamil Nadu, India, based on both morphological characteristics and molecular phylogenetic analysis using the Internal Transcribed Spacers (ITS) region of nuclear ribosomal DNA. The key morphological characters of the ascomata include the presence of a longitudinal slit remaining closed even at maturity. The ascospores biseriate having three septa with all the cells evenly pigmented including the terminal cells. The ascus measuring 115–122 × 20–22 μm. Ascospores initially two celled and finally become four celled, hyaline first, later changing to yellow and then dark brown, oblong to ellipsoid, 28–39 × 7–12 μm. The nrITS-based phylogenetic tree inferred from the Bayesian posterior probabilities indicate that H. madraspatanum is closely related to Hysterium pulicare, H. angustatum and H. rhizophorae. However, H. madraspatanum is morphologically distinct from them by having relatively larger spore size, shallow groove in the ascomata, spores with concolorous terminal cells. Therefore, is a novel species under the genus Hysterium. Azadirachta indica is reported in the study as a new host for the genus Hysterium.

Pseudosperma calciphilum (Inocybaceae), a new Mediterranean species from Sardinia (Italy), Malta, and Valencia (Spain)

A complete description is provided for Pseudosperma calciphilum (Inocybaceae, Agaricales), a new basidiomycete species from Sardinia (Italy), Malta, and Valencia (Spain) in Europe, along with colour photographs of its macro- and microscopic characters and a comparative study of the similarities and differences from its closest allies. The new species occurs on calcareous soils in Mediterranean habitats preferably under Quercus ilex subsp. ilex and Q. ilex subsp. rotundifolia. Pseudosperma conviviale resembles P. calciphilum in some macro- and microscopic features, but the latter is distinguished by having white velar remnants on pileus, larger spores and by its ecology, as it apparently grows exclusively on calcareous soils. The phylogenetic analyses based on nrITS and nrLSU nucleotide sequence data confirmed that the new species is a member of the former Inocybe section Rimosae sensu stricto, whose species are currently placed in the genus Pseudosperma. The closest relatives are P. melleum, P. conviviale, P. melliolens and P. umbrinellum, from which the new Mediterranean species is well distinguished both morphologically and genetically.

Starting from the Bottom: Coupling a Genetic Algorithm and a Pore Network Model for Porous Electrode Design

Porous electrodes are performance- and cost-defining components in modern electrochemical systems as they provide surfaces for electrochemical reactions, facilitate mass transport, conduct electrons and heat, and determine the hydraulic resistance [1]. Hence, electrode engineering is a valid approach to increase power density and improve const competitiveness. In convection-enhanced technologies, currently used porous materials are fibrous carbonaceous electrodes developed for low temperature fuel cells; yet their microstructure and surface chemistry limits the performance of emerging electrochemical systems such as redox flow batteries. Moreover, the empirical design of these electrodes is time- and resource-intensive which limits exploration of the wider design space. Microstructure-informed multiphysics simulations can be leveraged to aid the theoretical understanding and design of advanced electrode architectures [2]. However, while these simulations have improved our understanding, they have only recently [3] been deployed to realize the bottom-up design of electrode microstructures. The combination of microstructure-informed multiphysics with evolutionary algorithms could accelerate progress in the optimization of porous electrodes for specific applications. In this work, we deploy three-dimensional simulations in combination with a genetic algorithm for the bottom-up design of porous electrodes for redox flow batteries.In the first part of the talk, the coupling of a pore network modeling framework [4] with an evolutionary algorithm [5] is described. The pore network model is a microstructure-informed, electrolyte-agnostic simulation framework for flow batteries utilizing a network-in-series approach to account for species depletion over the entire length of the electrode, developed using an open-access platform (OpenPNM) [6]. The electrochemical model is solved for the electrolyte fluid transport and couples both half-cells by iteratively solving the species and charge transport at a low computational cost. In the genetic algorithm, the electrode microstructure evolves driven by a fitness function that minimizes pumping power requirements and maximizes electrochemical power output, where the optimization only relies on the electrolyte chemistry and initial electrode morphology and flow field geometries as inputs. The analyzed proof-of-concept employs a flow-through cubic lattice structure with fixed pore positions and shows significant improvement of the fitness function over 1000 generations, where the fitness improved by 75% predominantly driven by reducing the pumping requirements by 73%. The evolutionary design resulted in a bimodal pore size distribution containing longitudinal electrolyte flow pathways of larges pores. Additionally, we found an increase in surface area at the membrane-electrode interface resulting in a 42% enhancement of the electrochemical performance.In the second part of the talk, I will discuss our latest progress in the development of the topology optimization by implementing commercial fibrous electrodes as offspring networks, integrated flow field geometries, and extended evolutionary freedom during the optimization. Coupling the genetic optimization to the desired flow field geometry affects the evolution of the fitness function, shifting the balance between electrochemical and hydraulic performance, highlighting the importance of the coupled optimization of flow fields and electrodes. By including more evolutionary freedom in the algorithm (i.e., by allowing merging and splitting of pores outside fixed coordinates), existing fibrous electrodes can be enhanced by for example reducing their pumping losses. The presented genetic algorithm offers great potential for the predictive design of electrode microstructures tailored for specific reactor architectures and redox chemistries. Hence, this framework can be used to accelerate and broaden the design and fabrication process of advanced electrode structures. Although applied to flow batteries in this study, the methodology can be leveraged to advance electrode microstructures in other electrochemical systems by adapting the relevant physics.

EVALUATION OF ENTEROCYTOZOON HEPATOPENAEI (EHP) IN FARMED PENAEUS VANNAMEI IN TAIWAN

Enterocytozoon hepatopenaei (EHP) was first described in Thailand in 2009 and has since been identified as a significant threat to the shrimp aquaculture industry. Recently, intracellular microsporidia were identified as a causative agent of hepatopancreatic microsporidiosis (HPM). To date, HPM has been listed as an emerging threat to shrimp farming industries because of reduced shrimp growth and survival rates which are considered to be a wasting disease. This study investigated the outbreaks of HPM in farmed Penaeus vannamei in Taiwan. Sixty-five shrimp samples were collected from Taiwan. The proportion of HPM-positive cases was 48% (31/65). Additionally, the gross signs in infected shrimp were stunted growth, sloughed hepatopancreas (HP), and lethargy. The smear impression on the HP also revealed the existence of large EHP spores. Nested-PCR findings identified that 9 cases were confirmed to be positive for the EhSWP1 gene in the first step and 22 cases tested positive for the second step. Phylogenetic analysis of EHP from Taiwan showed 100% similarity to EHP from Thailand, India, and the United States. Histopathological analysis of the HP revealed haemocyte infiltration and the presence of EHP spores in the hepatopancreatic tubule epithelial cells. These results demonstrated that EHP is the main cause in shrimp farms in Taiwan.

Altitudinal Gradient and Soil Depth as Sources of Variations in Fungal Communities Revealed by Culture-Dependent and Culture-Independent Methods in the Negev Desert, Israel.

We examined fungal communities in soil profiles of 0-10 cm depth along the altitudinal gradient of 250-530-990 m.a.s.l. at the Central Negev Desert, Israel, which benefit from similar annual precipitation (95 mm). In the soil samples collected in the summer of 2020, a mycobiota accounting for 169 species was revealed by both culture-dependent and culture-independent (DNA-based) methodologies. The impact of soil depth on the variations in fungal communities was stronger than the impact of altitude. Both methodologies displayed a similar tendency in the composition of fungal communities: the prevalence of melanin-containing species with many-celled large spores (mainly Alternaria spp.) in the uppermost layers and the depth-wise increase in the proportion of light-colored species producing a high amount of small one-celled spores. The culturable and the DNA-based fungal communities had only 13 species in common. The differences were attributed to the pros and cons of each method. Nevertheless, despite the drawbacks, the employment of both methodologies has an advantage in providing a more comprehensive picture of fungal diversity in soils.

Pseudobaeospora taluna (Fungi: Agaricales) newly described from southern Australia

Pseudobaeospora taluna is formally described from southern Australia, representing the first report of the genus from Australia given that P. lamingtonensis is excluded from the genus. Analysis of sequences of the internal transcribed spacer (ITS) shows that P. taluna is a distinct phylogenetic species. The distinctive morphological characteristics of the species are the combination of a pinkish grey to dull grey pileus, pale rhizomorphs at the base of the stipe extending into soil, thick-walled dextrinoid spores, presence of cheilo- and pleurocystidia, and a trichoderm pileipellis that stains bluish green in KOH. Three of the examined collections, from Tasmania, were 4-spored but a single collection from Victoria produced 2-spored basidia. Apart from the 2-spored basidia and larger spores, this 2-spored collection was similar in morphological and sequence characters to the 4-spored collections and is placed under P. taluna. The specific epithet was chosen in collaboration with the Tasmanian Aboriginal Centre and the palawa kani Language Program. In palawa kani, the language of Tasmanian Aborigines, taluna is the name of the Huon River area, where the holotype was collected.

Structure of Microbial Communities and Biological Activity in Tundra Soils of the Euro-Arctic Region (Rybachy Peninsula, Russia).

The relevance of the Arctic regions' study is rapidly increasing due to the sensitive response of fragile ecosystems to climate change and anthropogenic pressure. The microbiome is an important component that determines the soils' functioning and an indicator of changes occurring in ecosystems. Rybachy Peninsula is the northernmost part of the continental European Russia and is almost completely surrounded by Barents Sea water. For the first time, the microbial communities of the Entic Podzol, Albic Podzol, Rheic Histosol and Folic Histosol as well as anthropogenically disturbed soils (chemical pollution and human impact, growing crops) on the Rybachy Peninsula were characterized using plating and fluorescence microscopy methods, in parallel with the enzymatic activity of soils. The amount and structure of soil microbial biomass, such as the total biomass of fungi and prokaryote, the length and diameter of fungal and actinomycete mycelium, the proportion of spores and mycelium in the fungal biomass, the number of spores and prokaryotic cells, the proportion of small and large fungal spores and their morphology were determined. In the soils of the peninsula, the fungal biomass varied from 0.121 to 0.669 mg/g soil. The biomass of prokaryotes in soils ranged from 9.22 to 55.45 μg/g of soil. Fungi predominated, the proportion of which in the total microbial biomass varied from 78.5 to 97.7%. The number of culturable microfungi ranged from 0.53 to 13.93 × 103 CFU/g in the topsoil horizons, with a maximum in Entic Podzol and Albic Podzol soils and a minimum in anthropogenically disturbed soil. The number of culturable copiotrophic bacteria varied from 41.8 × 103 cells/g in a cryogenic spot to 5551.3 × 103 cells /g in anthropogenically disturbed soils. The number of culturable oligotrophic bacteria ranged from 77.9 to 12,059.6 × 103 cells/g. Changes in natural soils because of anthropogenic impact and a change in vegetation types have led to a change in the structure of the community of soil microorganisms. Investigated tundra soils had high enzymatic activity in native and anthropogenic conditions. The β-glucosidase and urease activity were comparable or even higher than in the soils of more southern natural zone, and the activity of dehydrogenase was 2-5 times lower. Thus, despite the subarctic climatic conditions, local soils have a significant biological activity upon which the productivity of ecosystems largely depends. The soils of the Rybachy Peninsula have a powerful enzyme pool due to the high adaptive potential of soil microorganisms to the extreme conditions of the Arctic, which allows them to perform their functions even under conditions of anthropogenic interference.

Jirovecia branchilis n. sp. (Microsporidia) from glands of Branchiura sowerbyi (Oligochaeta: Tubificidae) in China

Jirovecia species primarily infect oligochaetes and are typically characterized by large rod-shaped spores with a tail-like posterior prolongation. Presently, seven Jirovecia spp. are reported worldwide with only one described in China. Here, a new species, Jirovecia branchilis n. sp. was discovered in glands of oligochaetes Branchiura sowerybi Beddard, 1892 in China. Jirovecia branchilis n. sp. elicited the formation of numerous opaque xenomas of 0.12 to 0.20 mm (n = 30) in diameter. Electron microscopic observations demonstrated that the earliest developmental stages observed were uninucleate meronts residing directly with the host cytoplasm. Mature spores were rod-shaped with blunt ends and possessed a collar-like anchoring disk, a manubrium-type polar filament, a bipartite polarplast, and a three-layered spore wall. A tail-like prolongation was distinctly observed in the posterior of spores and measured 13.2–28.6 μm long (n = 30). Jirovecia branchilis n. sp. showed 98.54% sequence similarity with Janacekia tainunus isolated from the fat body of chironomidae larvae Kiefferulus tainanus based on obtained partial SSU rDNA gene sequence, but was significantly different in morphology, host, and infection sites. SSU rDNA-based phylogenetic analysis indicated Jirovecia branchilis n. sp. clustered with Janacekia tainanus within the Jirovecia-Bacillidium-Janacekia clade. In conclusion, a new species within Jirovecia, Jirovecia branchilis n. sp. is erected herein based mainly on its morphological, ecological, and to a lesser degree on its molecular characteristics. The whole relationship between Jirovecia spp., Janacekia spp., and Bacillidium spp. is in need of revision and could potentially be elucidated by using additional makers and sequencing a broader diversity of the already described species.

Penicillium poederi and P. tirolense, two new species of section Torulomyces.

Here we describe two new species of the genus Penicillium section Torulomyces with solitary phialides. Penicillium poederi sp. nov. was isolated from volcanic soils in Iceland. Penicillium tirolense sp. nov. was isolated from a sporocarp of Serpula lacrymans. Both species are characterised by slow growth rates and the production of a brown soluble pigment on CYA, conidiophores with solitary ampulliform phialides with smooth-walled stipes and warty, globose conidia and with connectives without visible rings. The spores of. P. poederi are 2.5 μm diam, while the spores of P. tirolense are 2.0 μm diam. In a multigene phylogeny based on the ITS, BenA, CaM and RPB2 gene regions P. tubakianum and P. wollemiicola are the closest relatives of P. poederi. This species differs from P. tubakianum and P. wollemiicola by its growth rates and by its pigmentation. The holotype of P. poederi is IB2017/0007, while SF014017 (CBS 147622) is a culture derived from the holotype. The closest relatives of P. tirolense are P. austricola and P. riverlandense. It differs from P. austricola by lower growth rates on all tested media and temperatures and by its larger spores. It differs from P. riverlandense by lower growth rates and the absence of growth at 37 °C. The holotype of P. tirolense is IBF2019/0162, while SF015108 (CBS 147625) is a culture derived from the holotype. Citation: Kirchmair M, Embacher J, Heimdörfer D, Walch G, Neuhauser S (2022). Penicillium poederi and Penicillium tirolense, two new species of section Torulomyces. Fungal Systematics and Evolution 10: 91-101. doi: 10.3114/fuse.2022.10.03.

Temperature and Humidity Regulate Sporulation of Corynespora cassiicola That Is Associated with Pathogenicity in Cucumber (Cucumis sativus L.).

Cucumber target leaf spot, caused by Corynespora cassiicola, is an emerging disease with a high incidence that causes severe damage to cucumbers on a global scale. Therefore, efforts need to be undertaken to limit the spread and infection of this pathogen, preferably by using environmentally friendly methods. In this study, the effects of temperature and moisture on the sporulation of C. cassiicola were investigated in vitro and in vivo. The novelty of our study refers to the observation of spore production and size as well as the revelation of a correlation between spore size and virulence. On potato dextrose agar (PDA) and cucumber-leaf extract agar (CEA), temperature played a critical role in spore production, which was strongly influenced by both temperature and moisture on detached leaves and cucumber seedlings. Maximum spore production was found at 30 °C on PDA and 25 °C on CEA, cucumber detached leaves and living plants. Lower spore productions were observed with a stepwise change of 5 °C. In addition, the largest spore production was found at 100% relative humidity (RH) in comparison to the other tested moisture. Moreover, moisture was found to be the most important factor affecting spore size, accounting for 83.09-84.86% of the total variance in length and 44.72-73.10% of the total variance in width. The longest-narrowest spores were formed at 100% RH, and the shortest-widest spores were formed at 75% RH. Furthermore, the result showed that larger spores of C. cassiicola were more virulent and small spores were avirulent. Our findings will contribute to the development of new strategies for the effective alleviation and control of cucumber target leaf spot.

Myriopteris grusziae: A New Species from Texas and Oklahoma Segregated from the Chihuahuan Desert Taxon M. scabra (Pteridaceae)

Abstract— Myriopteris scabra (until recently called Cheilanthes horridula) is a xeric-adapted fern species, endemic to the southwestern United States and northern Mexico. It is one of the most recognizable ferns in North America due to the unusual nature of the indument present on its adaxial leaf surfaces. This consists of rigid, multicellular trichomes with glassy, needle-like apices and compact conical bodies that are partially embedded in the leaf surface to form swollen, pustulate bases. Despite the seemingly distinctive nature of M. scabra, published chromosome counts indicate that collections assigned to this taxon encompass both diploids (n = 29) and tetraploids (n = 58). Here we investigate this case of cryptic diversity by integrating data from cytogenetic and spore analyses, observations of sporophyte morphology, and geographic distributions. Myriopteris scabra s.l. is shown to comprise two genetically disparate, morphologically recognizable taxa that exhibit little or no geographic overlap. The tetraploid taxon is described as a new species, M. grusziae, which completely supplants diploid M. scabra in the northeastern portion of its range (central Texas and south-central Oklahoma). This presumed allotetraploid is most like M. scabra but differs in having ultimate segments with adaxial trichomes that are longer, more flexible, mostly linear, and superficially attached. In addition, tetraploid M. grusziae has larger, more abundant scales that largely conceal the dark, sclerified leaf rachises, and it produces consistently larger spores than diploid M. scabra. We hypothesize that M. grusziae is an allotetraploid hybrid that acquired half of its chromosomes from M. scabra. However, the identity of the other diploid parent has yet to be resolved.

Algaria overbergensis Hedd. & R.H.Zander, a new moss species from the Overberg Rûens Shale Renosterveld system of the Southwest Cape, South Africa

ABSTRACT Introduction The moss genus Algaria currently comprises a single species known only from the type locality. During recent bryological surveys of remnant Overberg Renosterveld patches, plants were collected that clearly belong to this genus but differ from the only known species in several critical respects. Here, we describe these as a new species. Methods Specimens were rehydrated in the laboratory, dissected, and mounted in Hoyer’s solution or polyvinyl alcohol–glycerine. Observations and measurements were made using standard stereo and compound microscopy. Spore anatomy was further investigated using scanning electron microscopy. Key results and conclusions Algaria overbergensis Hedd. & R.H.Zander is described as a new species currently known from only three localities in Overberg Rûens Renosterveld. It is readily distinguished from its only congener (Algaria natalieae Hedd. & R.H.Zander) by its rounder capsule with a domed to conical operculum, epapillose calyptra, much larger spores, and truncate leaves with a narrower border of elongate cells.

Two new varieties of Russula Pers. (Basidiomycota: Russulaceae) from Sal forests of Shiwaliks, India

This paper deals with two new varieties of Russula species, R. camarophylla var. reticulospora var. nov. and R. aurea var. minuta var. nov. These were collected from the Shiwalik range of northwestern India, in association with Shorea robusta. Russula aurea var. minuta differs from R. aurea in having small sized sporophores, dentate to wavy gill edges with golden or yellow deposition instead of smooth and much smaller spores. Whereas, mushroom R. camarophylla var. reticulospora is close to Russula camarophylla except for the larger carpophores that have white cream pileus surface and larger spores. In basidiospores warts are connected to form mostly complete reticulum instead of mostly isolated warts reported in Russula camarophylla. In view of the presence of some unique varied features in the presently examined collections two new varieties of Russula has been proposed.

Understanding the appearance of heterospory and derived plant reproductive strategies in the Devonian

AbstractThe evolution of different spore size classes, or heterospory, is a fundamental reproductive innovation in land plants. The appearance of heterospory is particularly notable during the Devonian, when most known origins of the trait occur. Here we provide a perspective on the evolution of heterospory during this time interval, particularly from the late Early Devonian through the Middle Devonian (Emsian to Givetian Stages; 408–383 Ma), which shows an unusually high concentration of heterospory origins. We use theoretical considerations and compilations of fossil and extant spore sizes to suggest that the basic features of most heterosporous lineages, large spores and gametophytes that mature within the spore wall, are difficult to evolve in combination, because large spores disperse poorly but small spores cannot support a functional gametophyte developing within their walls; evolving spores between 100 and 200 microns in diameter appears to represent a particularly important barrier for the evolution of heterospory. We then discuss why this barrier may have been lower in the Devonian, noting that the appearance and spread of heterospory is coincident with the emergence of peat-accumulating wetland habitats. We suggest that more widespread wetland habitats would have generally lowered barriers to the evolution of heterospory by reducing dispersal limitation in larger spores. Ultimately, we suggest that the initial evolution of heterospory may be explained by major changes in sedimentology, thought to have been driven by plant evolution itself, that increased the diversity of terrestrial depositional environments and led to a greater number of habitats where large spores could be successful.

Do fungal spore morphological traits correlate with allergenicity?

Fungal spores, like pollen, are identified as sources of allergens, yet fungal spore morphology, unlike pollen morphology, has not been correlated with allergenicity. In this study, we listed allergenic fungi reported from published literature and gathered information about their spore morphologies including the species’ lifestyle, the ability to produce mycotoxins, and the types of hypersensitivity reactions they induced. We tested the association of these spore traits with the hypersensitivity reaction through correspondence analysis with Chisquare as the measure of distance. Our research listed a total of 158 species of allergenic fungi belonging to 82 genera and 30 taxonomic orders. Most of the species (n = 122) elicited a Type I hypersensitivity reaction while 33 species had more than one hypersensitivity type (Types I-III-IV). The most common allergenic fungi belong to the genus Alternaria (41 species). Two fungal taxa commonly found in spoiled food, Penicillium (9 species) and Aspergillus (8 species), were also listed as allergenic. We did not find any strong correlation between allergenic reaction with the following spore traits: shape, texture, color, size, appendages, and with the type of spores, presence of mycotoxins, and the species lifestyle. However, spore length and width were positively associated with hypersensitivity reaction. Allergenic fungi with short and/or narrow spores can likely cause multiple types of hypersensitivity reactions while fungi with large and/or wide spores can induce either Type I or Type III hypersensitivity reaction. Our research study provides interesting insights into the role of fungal spore morphologies in human allergenicity.

The early fossil record of glomeromycete fungi: New data on spores associated with early tracheophytes in the Lower Devonian (Emsian; c. 400 Ma) of Gaspé (Quebec, Canada)

Fossil assemblages in the fluvial to coastal deposits of the Early Devonian Battery Point Formation (400–395 Ma; Gaspé Bay, Quebec, Canada) are among the most diverse occurrences of Early Devonian permineralized plants worldwide. The plants host microbial and fungal material, which was studied in cellulose acetate peels and thin sections. The fossil fungal material includes spores that show affinities to the Glomeromycotina, preserved in trimerophyte axes. The spores fall into two size categories, both characterized by complex wall layering and hyphal attachments. Spores in the small category (40–65 μm) occur in a single axis and exhibit few informative features. The most frequently occurring type is the large spores (90–240 μm) that are placed into the new species Glomites oqoti. These spores exhibit four wall layers (when well preserved), of which two are always present: a thick, dark layer and a thin, membranous layer. Several lines of circumstantial evidence suggest that the spores were metabolically active within their plant hosts at the time of fossilization and that the plants were alive at the time of colonization. These observations, along with comparisons with other fossil glomeromycetes and the life history traits of living glomeromycetes, suggest that G. oqoti held an endomycorrhizal role. The Battery Point Formation fossils represent the only Early Devonian glomeromycete occurrence documented outside the Rhynie Chert hot spring deposits. Their occurrence in fluvial-coastal environments and their putative mycorrhizal role suggest that glomeromycetes were relatively ubiquitous symbionts of tracheophytes, like their extant counterparts, by the Early Devonian.

Anthoceros subtilis and A. telaganus (Anthocerotaceae): two new records for America from the hornwort flora of Mexico

In a recent trip to southern Mexico, Anthoceros subtilis and A. telaganus were recorded for the first time in Mexico and the American continent. Several previous records of A. subtilis were from Asia and one from Africa, and A. telaganus is known only from Indonesia. The new range extension of these two species is reported and the species are described and illustrated. Mexican populations of A. subtilis are characterized by small brown spores (26–42 μm), similar ornamentation on proximal and distal spore surfaces with papillate to tuberculate projections. Anthoceros telaganus is characterized by larger black spores (32–53 μm) with a smooth strip along the trilete mark on the proximal surface. Molecular genetic sequencing is needed to test whether Asian and American populations of these morphologically similar but geographically disjunct taxa are conspecific.

Corrigendum: Pykälä J, Kantelinen A, Myllys L (2020) Taxonomy of Verrucaria species characterised by large spores, perithecia leaving pits in the rock and a pale thin thallus in Finland. MycoKeys 72: 43–92. https://doi.org/10.3897/mycokeys.72.56223

Corrigendum