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FIGURE 5 in Pseudotomentella badjelanndana, Pseudotomentella sorjusensis and Tomentella viridibasidia-three new corticioid Thelephorales species from the Scandes Mountains
No full textFIGURE 5. Morphological features of T. viridibasidia, mounted in KOH and macroscopically. A, B basidiospores in frontal face; C, D in lateral face; E microscopic overview; F mature basidiome (holotype). The scale bar represents 10 µm.Published as part of Svantesson, Sten, Larsson, Karl-Henrik & Larsson, Ellen, 2021, Pseudotomentella badjelanndana, Pseudotomentella sorjusensis and Tomentella viridibasidia-three new corticioid Thelephorales species from the Scandes Mountains, pp. 61-78 in Phytotaxa 497 (2) on page 73, DOI: 10.11646/phytotaxa.497.2.1, http://zenodo.org/record/542383
FIGURE 4 in Pseudotomentella badjelanndana, Pseudotomentella sorjusensis and Tomentella viridibasidia-three new corticioid Thelephorales species from the Scandes Mountains
No full textFIGURE 4. Morphological features of P. sorjusensis, mounted in KOH and macroscopically. A, B basidiospores in frontal face; C, D in lateral face; E microscopic overview; F mature basidiome (holotype). The scale bar represents 10 µm.Published as part of Svantesson, Sten, Larsson, Karl-Henrik & Larsson, Ellen, 2021, Pseudotomentella badjelanndana, Pseudotomentella sorjusensis and Tomentella viridibasidia-three new corticioid Thelephorales species from the Scandes Mountains, pp. 61-78 in Phytotaxa 497 (2) on page 71, DOI: 10.11646/phytotaxa.497.2.1, http://zenodo.org/record/542383
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Pseudotomentella sorjusensis Svantesson & Larsson & Larsson 2021, sp. nov.
No full textPseudotomentella sorjusensis Svantesson, sp. nov. (Fig. 4) MycoBank No.: MB 835163. UNITE SH: SH1185284.08 FU. Etymology: the name refers to Sorjus, an older spelling of the type locality. Type: SWEDEN. Lule Lappmark: Jokkmokk, Sårjås N, low alpine heath on ground with intermediate pH, on underside of stone, 17 August 2016, S . Svantesson 298 (holotype: GB!, GenBank Acc. No. ITS: MT 146448). Basidiome annual, resupinate, membranaceous; effused to approximately five centimetres in diameter. Mature parts continuous, with a firm, fibrous and compact yet soft and rather elastic texture. Hymenium smooth; greenish brown when fresh, brown with a reddish hue when dried. Immature parts discontinuous, byssoid with a cottony texture. Subhymenium and hymenium of immature parts blue grey when fresh, blue grey to grey brown when dried. Subiculum well-developed, loose, fibrous, brown; forms the outer edge of the basidiome, extending noticeably beyond the hymenium. Hyphal cords lacking, but loose bundles of subicular hyphae sometimes present. Hyphal system monomitic, clamp connections absent from all hyphae. Subicular hyphae noticeably long and straight, thick-walled; forming a loose tissue. Individual hyphae (3.0–) 3.1–4.3 μm wide, with a mean width of 3.6 μm; brown to orange brown in KOH, orange brown in water; inamyloid. Subhymenial hyphae often somewhat sinuous, thin to thick-walled; forming a rather dense tissue. Individual hyphae 3.3–5.2 (–5.5) μm wide, with a mean width of 4.3 μm; hyaline to brown in KOH, with a green or blue green reaction in the presence of air; pale green to pale orange green in water, with strongly granular contents; occasionally amyloid. Encrustation none observed. Basidia with four slightly curved sterigmata, occasionally two-sterigmate; clavate to narrowly clavate, sometimes clavopedunculate, thin-walled, with one–three slight constrictions. Dimensions: 41–56 (–59) × (10.1–) 10.3–12.1 (– 12.6) μm; mean dimensions: 48 × 11.5 μm. Sterigmata (7.0–) 7.2–8.9 (–9.2) μm long, with a mean length of 8.0 μm. Colours and reactions the same as for subhymenial hyphae; amyloid reaction most frequently found at the bases of basidia. Cystidial organs lacking. Basidiospores in frontal face generally with a subcircular or triangular basic shape and an angular, nodulose, triangular or sometimes cross-shaped outline, covered in bi-or trifurcate, sometimes singularly attached, echinuli. A majority of the spores with three-five distinct, rounded to square lobes; seven-lobed spores occasionally occurring; abnormally large spores originating from two-sterigmate basidia infrequently seen. Frontal dimensions: 7.4 – 8.6 (–9.1) × 7.7–8.8 (–9.1) μm; mean dimensions: 8.1 × 8.2 μm; Q-value: 0.9–1.1; mean Q-value: 1.0. Echinuli (0.5–) 0.6–0.8 μm long, with a mean length of 0.7 μm. Lateral face ellipsoid to ovoid, with evenly rounded edges or one–three lobes. Lateral dimensions: 7.4–8.5 × (5.0–) 5.2–6.3 (–6.5) μm; mean dimensions: 7.9 × 5.8 μm; Q-value: 1.2–1.5; mean Qvalue: 1.4. Colour in KOH pale brown to pale orange brown, in the presence of air sometimes with a green to blue green reaction; in water pale orange brown; occasionally amyloid. Chlamydospores lacking. Habitat The only specimen recorded to date of P. sorjusensis is the type collection, which was found in a low alpine heath on ground with intermediate pH. UNITE sequence metadata show that the species forms ectomycorrhiza with at least Picea abies (L.) H. Karst., Picea glauca (Moench) Voss, Salix arctica Pall. and Salix caprea L. (Kõljalg et al. 2005, Nilsson et al. 2018). One of the root tip sequences originate from an arctic locality, while the remaining sequences in the UNITE SH come from temperate forests in lowland areas. Distribution Basidiomata encountered in: Sweden. Root tip samples confirm presence also in Estonia (3), Canada (2), and soil samples in Estonia (56) and Latvia (2). Remarks Within the P. tristis group, the basidiome of P. sorjusensis can be recognised by its lack of hyphal cords and skeletal hyphae, its dense, compact texture after drying, bluish colour of immature parts, narrow subicular hyphae and its short spores. Two species, P. badjelanndana and P. rotundispora are similar to P. sorjusensis. Pseudotomentella badjelanndana has thinner subhymenial hyphae, whose mean diameter is smaller than its subicular hyphae. Its spores are also generally longer than wide and have longer echinuli but a larger frontal face than in P. sorjusensis. Pseudotomentella rotundispora differs from P. sorjusensis by slightly thinner subhymenial hyphae, which are of more or less equal width to its subicular hyphae and by its spores, which are slightly shorter in frontal face. For further notes on the morphological separation of species within the P. rotundispora group see Remarks under the description of P. badjelanndana. Other described species within the group can appear similar, but have either wider hyphae, longer spores or both.Published as part of Svantesson, Sten, Larsson, Karl-Henrik & Larsson, Ellen, 2021, Pseudotomentella badjelanndana, Pseudotomentella sorjusensis and Tomentella viridibasidia-three new corticioid Thelephorales species from the Scandes Mountains, pp. 61-78 in Phytotaxa 497 (2) on pages 71-72, DOI: 10.11646/phytotaxa.497.2.1, http://zenodo.org/record/542383
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Taxonomy and Systematics of Thelephorales – Glimpses Into its Hidden Hyperdiversity
No full textThe order Thelephorales is a widespread group of many thousands of species of ecologically important, ectomycorrhizal fungi, of which only a fraction have been described to date. Most species are corticioid (skin-like) and form complexes of morphologically similar, closely related species. At the same time the names that do exist are often old, have unclear synonymy and their common presence within such complexes often hinders the description of new species. For the comparatively few stipitate (with cap and stipe) Thelephorales species taxonomic knowledge is more complete but the phylogenetic relationships between taxa is largely unknown; most existing genera have been circumscribed based on macromorphology. Many stipitate species occurring in the Nordic countries are dependent on old growth forest and are hence included in the national Red Lists, while the conservational situation for nearly all corticioid species is unknown, due to their unclear taxonomy. Pseudotomentella tristis s.l. is a seemingly common, widespread and ecologically very plastic, corticioid morphospecies with an old name and nine heterotypic synonyms. Through a combination of type studies, precise spore measurements, ecological data and a multi-gene phylogeny, three species are identified under already existing names and another ten are described as new. One species, P. umbrina, is found to indeed be a common and widespread species with a wide ecological amplitude, while the remaining 12 are less common, possibly less widespread, have narrower ecological niches and in a few cases seem to be host-restricted. In similarity to stipitate species, a large proportion of the newly described species seem to only occur in old growth forest. Three corticioid species from the Scandes mountains, two Pseudotomentella species and one Tomentella, are described as new, based on ITS-LSU phylogenies. The Pseudotomentella species belong to the P. tristis group, where they are more or less cryptic with another newly described species. A new, stipitate species in the hitherto corticioid genus Amaurodon is described, the stipitate genera Hydnellum and Sarcodon are delimited against each other and the stipitate genus Polyozellus is delimited against the corticioid genus Pseudotomentella – the former two with phylogenies based on ITS and LSU sequences and the latter based on a multi-gene dataset. Hydnellum is found to make Sarcodon paraphyletic, as does Polyozellus Pseudotomentella. To amend this, twelve species are recombined from Hydnellum to Sarcodon, while all species, including the type, are moved from Pseudotomentella to Polyozellus. In conclusion, this thesis demonstrates that corticioid species complexes in Thelephorales with many taxa and old names can be successfully disentangled and presents a method for doing so; it identifies molecular markers and sets a standard of measuring spores and collating ecological data that will facilitate further taxonomic work within the order. In addition, it shows that basidiomata shape is a poor predictor of generic affinity, even when derived from such striking differences as the separation of stipitate and corticioid forms. Consequently, the extinction threat previously documented for stipitate species is likely not restricted to such, and this is also tentatively shown for corticioid Polyozellus species
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Taxonomy and Systematics of Thelephorales – Glimpses Into its Hidden Hyperdiversity
Full text linkThe order Thelephorales is a widespread group of many thousands of species of ecologically important, ectomycorrhizal fungi, of which only a fraction have been described to date. Most species are corticioid (skin-like) and form complexes of morphologically similar, closely related species. At the same time the names that do exist are often old, have unclear synonymy and their common presence within such complexes often hinders the description of new species. For the comparatively few stipitate (with cap and stipe) Thelephorales species taxonomic knowledge is more complete but the phylogenetic relationships between taxa is largely unknown; most existing genera have been circumscribed based on macromorphology. Many stipitate species occurring in the Nordic countries are dependent on old growth forest and are hence included in the national Red Lists, while the conservational situation for nearly all corticioid species is unknown, due to their unclear taxonomy. Pseudotomentella tristis s.l. is a seemingly common, widespread and ecologically very plastic, corticioid morphospecies with an old name and nine heterotypic synonyms. Through a combination of type studies, precise spore measurements, ecological data and a multi-gene phylogeny, three species are identified under already existing names and another ten are described as new. One species, P. umbrina, is found to indeed be a common and widespread species with a wide ecological amplitude, while the remaining 12 are less common, possibly less widespread, have narrower ecological niches and in a few
cases seem to be host-restricted. In similarity to stipitate species, a large proportion of the newly described species seem to only occur in old growth forest.
Three corticioid species from the Scandes mountains, two Pseudotomentella species and one Tomentella, are described as new, based on ITS-LSU phylogenies. The Pseudotomentella species belong to the P. tristis group, where they are more or less cryptic with another newly described species.
A new, stipitate species in the hitherto corticioid genus Amaurodon is described, the stipitate genera Hydnellum and Sarcodon are delimited against each other and the stipitate genus Polyozellus is delimited against the corticioid genus Pseudotomentella – the former two with phylogenies based on ITS and LSU
sequences and the latter based on a multi-gene dataset. Hydnellum is found to make Sarcodon paraphyletic, as does Polyozellus Pseudotomentella. To amend this, twelve species are recombined from Hydnellum to
Sarcodon, while all species, including the type, are moved from Pseudotomentella to Polyozellus.
In conclusion, this thesis demonstrates that corticioid species complexes in Thelephorales with many taxa and old names can be successfully disentangled and presents a method for doing so; it identifies molecular markers and sets a standard of measuring spores and collating ecological data that will facilitate further taxonomic work within the order. In addition, it shows that basidiomata shape is a poor predictor of generic affinity, even when derived from such striking differences as the separation of stipitate and
corticioid forms. Consequently, the extinction threat previously documented for stipitate species is likely not restricted to such, and this is also tentatively shown for corticioid Polyozellus species
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