Phylogeny and evolution of morphological structures in a highly diverse lineage of fruiting-body-forming amoebae, order Trichiales (Myxomycetes, Amoebozoa).

Early phylogenetic studies refuted most previous assumptions concerning the evolution of the morphological traits in the fruiting bodies of the order Trichiales and did not detect discernible evolutionary patterns, yet they were based on a limited number of species. We infer a new Trichiales phylogeny based on three independently inherited genetic regions (nuclear and mitochondrial), with a fair taxonomic sampling encompassing its broad diversity. Besides, we study the evolutionary history of some key morphological characters. According to the new phylogeny, most fruiting body traits in Trichiales systematics do not represent exclusive synapomorphies or autapomorphies for most monophyletic groups. Instead, the evolution of the features derived from the peridium, stalk, capillitium, and spores showed intricate patterns, and character state transitions occurred rather within- than between clades. Thus, we should consider other evolutionary scenarios instead of assuming the homology of some characters. According to these results, we propose a new classification of Trichiales, including the creation of a new genus, Gulielmina, the resurrection of the family Dictydiaethaliaceae and the genus Ophiotheca, and the proposal of 13 new combinations for species of the genera Arcyria (1), Hemitrichia (2), Ophiotheca (2), Oligonema (4), Gulielmina (3), and Perichaena (1).

Circumflex Scapular Artery Pseudoaneurysm as an Unusual Source of Emboli in Recurrent Posterior Circulation Stroke.

OBJECTIVE: To present a rare cause of recurrent posterior embolic strokes originating from a partially thrombosed pseudoaneurysm of a shoulder artery after arthroscopy. MATERIALS AND METHODS: The clinical history, complementary studies and follow-up were reviewed. RESULTS: The patient was successfully embolized and presented no new ischemic episodes at the 3-month follow-up visit. CONCLUSIONS: Shoulder artery pseudoaneurysm should be considered as an unusual source of posterior embolic strokes.

Considerations and consequences of allowing DNA sequence data as types of fungal taxa.

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.

Understanding lichenicolous heterobasidiomycetes: new taxa and reproductive innovations in Tremella s.l.

Four new lichenicolous Tremella species are described and characterized morphologically and molecularly. Tremella celata grows on Ramalina fraxinea, inducing the formation of inconspicuous galls, and having hyphae with incomplete clamps. Tremella endosporogena develops intrahymenially in the apothecia of Lecanora carpinea, having single-celled basidia and clampless hyphae. Tremella diederichiana is the name proposed for a species micromorphologically close to T. christiansenii but inducing the formation of small, pale galls on the thallus and apothecia of Lecidea aff. erythrophaea Tremella variae grows on Lecanora varia thallus, instead of on the apothecia, as do the other known Tremella species parasitizing Lecanora s.l. Phylogenetic relationships and host specificity of these species are investigated and compared with other taxa that show morphological resemblances, phylogenetic affinities or similar hosts. The formation of mitotic conidia inside old basidia (endospores), which is a poorly known reproductive strategy in the Basidiomycota, is also a distinctive character of Tremella endosporogena A discussion on the reproductive role and systematic implications of endospores is included.

Combining morphological and phylogenetic analyses to unravel systematics in Geastrum sect. Schmidelia.

Systematics of the recently proposed Geastrum sect. Schmidelia are addressed through statistical analyses of quantitative morphological variables and phylogenetic reconstructions based on a multilocus approach. Emphasis is given to the taxonomic placement of G. schmidelii var. parvisporum. This variety is found to be not phylogenetically close to G. schmidelii var. schmidelii, the type species of G. sect. Schmidelia, and it therefore is excluded from this section, taxonomically raised to species rank (as G. parvisporum) and included as a member of G. sect. Hariotia. A second species in G. sect. Schmidelia is recognized and formally described as G. senoretiae. It is characterized by small basidiomata, non-hygrometric exoperidium, subsessile endoperidium and finely plicate, indistinctly delimited peristome, so far known only from Spain. Photographs and drawings are included, along with a comparison of morphologically close taxa. The presence of sclerified basidia in the mature gleba, previously not reported in the genus, is commented on.

Fístulas durales intracraneales: reporte de un caso y revisión de la literatura / Dural arteriovenous fistulas: case report and review

Las fístulas arteriovenosas durales, son malformaciones consistentes en corto circuítos entre las arterias durales y extracraneales con los senos venosos durales. Son causa de consulta por acúfenos, cefalea o déficit neurológico producto de sus complicaciones, como hemorragia subaracnoídea (HSA), hematoma intracerebral (HIC) o edema vasogénico. En cuanto a su origen, este puede ser congénito o adquirido; el diagnóstico y su clasificación se realizan en base a la clínica, tomografía axial computada (TAC) y resonancia nuclear magnética (RMN), siendo el gold estándar la angiografía cerebral.