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Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.

Type material of twelve species of Usnea related to Asia and South Africa were studied and one species from North America is newly described. Holotype specimens of eight Chinese taxa described in 1975 were synonymized as follows: U. mengyangensis is lectotypified and synonymized with U. aciculifera. Usnea recurvata and U. subrectangulata are synonymized with U. baileyi. Usnea kirinensis is synonymized with U. barbata s.str. Usnea crassiuscula and U. yunnanensis (= U. australis J.D. Zhao et al., nom. illeg. non Fr.) are synonymized with U. bismolliuscula. Usnea iteratocarpa is synonymized with U. cristatula (new to Asia, China). Usnea decumbens is synonymized with U. intumescens (new to Asia, China). Usnea entoviolata and U. roseola are synonymized with U. fragilis (new to Asia, China, India, Japan). The lectotype of Usnea trichoideoides was found to belong to the Usnea pectinata aggr. and consequently U. montis-fuji was resurrected for U. trichodeoides sensu Ohmura. Usnea ceratina and U. trichodeoides are excluded from the Japan lichen flora. Usnea macaronesica a recently described Macaronesian and South American species is synonymized with the Asian taxa U. pycnoclada. Usnea chicitae is described as a new species endemic of the Southern Appalachian Mountains. It is characterized by stipitate efflorescent soralia, a tenuicorticata-type of CMA and the presence of salazinic and psoromic acid in the medulla. [ABSTRACT FROM AUTHOR]

Usnea jezoformosana is described as a new species from East Asia. The morphology of this taxon is very similar to Usnea fragilescens but differs by the presence of granular soredia (instead of farinose soredia). It differs furthermore chemically by the presence of protocetraric acid (major) and barbatic acid (major to trace). The monophyly and independence of the newly described species from U. fragilescens and related taxa were inferred by a molecular phylogenetic tree based on ITS rDNA sequences. Usnea jezoformosana was collected in subboreal forests of Hokkaido (Japan) and in Taiwan where it grew on tree barks, building wood or cliffs. [ABSTRACT FROM AUTHOR]

Hypertensive men have a higher prevalence of erectile dysfunction (ED) than the general. population. Experimental evidence of ED in hypertensive animals is scarce. This study evaluates the erectile function of spontaneously hypertensive rats (SHR) and agematched normotensive Wistar-Kyoto rats (WKY) in vivo by the increase in intracavernosal pressure after electrical stimulation of the cavernous nerve (CN) and by isometric tension studies on corporal strips. Frequency-dependent erectile responses to CN stimulations were reduced in SHR. Phenylephrine induced lower corporal contractions in SHR although pD2 values were similar to WKY. Endothelium-dependent relaxations to ACh were impaired significantly in SHR, and indomethacin improved these relaxations in both WKY and SHR, the latter thus reaching values similar to WKY. Corporal relaxations to sodium nitroprusside were enhanced in SHR. Thus a dysfunctional [alpha]-adrenergic contraction of the corporal smooth muscle, an increased cyclooxygenase-dependent constrictor tone, and/or a defect in endothelium-dependent reactivity are associated with the altered erectile mechanisms in SHR. Drugs targeting endothelial dysfunction may delay the occurrence of ED as a complication of hypertension. hypertension; endothelial dysfunction; corpus cavernosum

This paper is a continuation of the new series started in 2020 to publish the new or interesting lichenological discoveries made in Switzerland or in the Geneva canton. Aspicilia crespiana is new to the Alps and to Switzerland. Candelariella blastidiata, C. faginea and C. oleaginescens are new to Switzerland. New observations for Candelariella plumbea s.l. and C. viae-lacteae in Switzerland are given. A key in French and in English for the species of Candelaria and Candelariella occurring in Switzerland is proposed. [ABSTRACT FROM AUTHOR]

INTRODUCTION The presence of heteromorphic sex chromosomes, i.e. sex chromosomes clearly distinguishable in form and genetic content, has been accompanied by the development of mechanisms of dosage compensation. Dosage compensation [...]

Using molecular data to delimit species or reconstruct their evolutionary history is now widely used across all organisms. However, such analyses can suffer from poor or false specimen identifications leading to incorrect conclusions. Here we show that the use of misidentified specimens in a phylogenetic framework resulted in questionable conclusions in a previously published study (Mark et al. 2016). Using morphological, chemical and statistical analyses on the specimens used in that study, we found support for Usnea barbata and U. dasopoga being morphologically and anatomically distinct species with separate clusters in the molecular phylogeny. Furthermore, our revision of specimen identifications refutes the synonymization of U. substerilis with U. lapponica. In conclusion, we discuss the issue of correct identification of voucher specimens in DNA databases and conclude with some general suggestions to avoid false specimen identifications in phylogenetic studies. [ABSTRACT FROM AUTHOR]