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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.

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The crinipelloid genera Crinipellis and Moniliophthora (Agaricales, Marasmiaceae) are characterized by basidiomes that produce long, dextrinoid, hair-like elements on the pileus surface. Historically, most species are believed to be saprotrophic or, rarely, parasitic on plant hosts. The primary morphological diagnostic characters that separate Crinipellis and Moniliophthora are pliant vs. stiff (Crinipellis) stipes and a tendency toward production of reddish pigments (ranging from violet to orange) in the basidiome in Moniliophthora. Additionally, most species of Moniliophthora appear to have a biotrophic habit, while those of Crinipellis are predominantly saprotrophic. Recently, several new neotropical collections prompted a morphological and phylogenetic analysis of this group. Herein, we propose a new species and two new combinations: Moniliophthora mayarumsp. nov., described from Belize, is characterized by its larger pileus and narrower basidiospores relative to other related species; Moniliophthora ticoicomb. nov. (= Crinipellis ticoi) is recollected and redescribed from biotrophic collections from northern Argentina; and M. brasiliensiscomb. nov. (= Crinipellis brasiliensis), a parasite of Heteropterys acutifolia. The addition of these three parasitic species into Moniliophthora support a hypothesis of a primarily biotrophic/parasitic habit within this genus.

The Paraguayan Chaco is an isolated environment with its own unique ecosystem. In this region, Chagas disease remains a health problem. Chagas disease is caused by the parasite Trypanosoma cruzi, and it is primarily transmitted by triatomines. In order to identify the blood meal sources of triatomines, specimens of the vector were collected in domestic and peridomestic areas and the PCR-RFLP method was implemented. Cytochrome b was amplified from the samples and later subjected to digestion with two restriction enzymes: Hae III and Xho I.It was possible to generate distinct restriction patterns on the amplified material to identify several blood meal sources for the vectors. We employed the blood from several species as positive controls: human, chicken, canine, feline, and armadillo blood. However, we identified only 3 sources for the blood meals of the insect vectors: human, chicken and canine blood. In total, 76 triatomines were captured. T. cruzi was not found in any of them. In 61% of the captured specimens, the blood meal sources for the vectors could be identified. In 30% of these cases, the presence of DNA from more than one vertebrate was detected in the same triatomine. The most common blood meal source found was chicken blood. The presence of human and chicken blood in triatomines captured in domestic and peridomestic areas strongly suggests that the parasite can freely move amongst both areas regardless of food availability. Free vector movement in these areas constitutes an epidemiological threat for the inhabitants of the community under study.

Twenty-eight soil samples were obtained from open fields and greenhouses used for tomato cultivation in various regions of Colombia. For functional characterization, 99 Bacillus thuringiensis (Bt) strains were isolated and characterized by abundance and morphology of microscopic crystals, SDS-PAGE of protein extracts and M-PCR analyses of genes of the cry1 family, as well as for their insecticidal activity against Tuta absoluta second instar larvae. Native Bt strains had amorphous (5%), bi-pyramidal (27%), square (8%), spherical (38%) and triangular (22%) crystal forms. Based on the presence of 1-4 different crystal forms, 18 different profiles were established. The SDS-PAGE analyses of protein extracts established ten different strain groups based on their protein band weight and potential biological activity. The M-PCR technique identified 35 native Bt strains based on the presence of the 6 genes cry1Aa, cry1Ab, cry1Ac, cry1B, cry1C and cry1D, whose frequency of occurrence was 76, 26, 21, 35, 32 and 8.8%, respectively. Thirteen different PCR profiles were found in native Bt strains. Several gene combinations tended to cooccur with elevated frequency, such as the pairs cry1Ac/ cry1C, cry1Ab/cry1Ac and cry1Ab/cry1B, for which Pearson correlation coefficients were 0.69, 0.52 and 0.54, respectively. Native strains ZBUJTL39 and ZCUJTL11 had up to three times higher biological activity against T. absoluta second instar larvae than the reference strain Bt var. kurstaki HD1, with an LD 50 of 2.4 lg/ml (P \ 0.05) for native Bt strain ZCUJTL11. This study suggests a high biodiversity of native Bt strains from tomato growing regions in Colombia, which has important implications for designing biological control strategies for T. absoluta.

The aim of this article is to describe two new setoid species of Marasmius: M. chrysoblepharioides and M. neotrichotus from the riparian forest of the Paraná river in Northeastern Argentina. Marasmius chrysoblepharioides is characterized by a sulcate-striate, yellowish orange pileus, an entirely pilose, orange brown stipe; caulosetae with a tapering and thick-walled apex, and its bacilliform to fusiform basidiospores. Marasmius neotrichotus differs from M. trichotus and M. ciliatus by its longer caulosetae and spores, respectively. The phylogenetic analyses based on molecular data from ITS sequences indicated that both new species are distinct from closely related species.

ResumenSe describen e ilustran tres especies de Volvariella para el Norte de la Argentina: V. taylorii, conocida para las selvas de Yungas y Paranaense; V. subxerophytica, conocida exclusivamente para los bosques xerófilos de la región chaqueña y V. pusilla encontrada en las provincias del Chaco y Tucumán. Las dos primeras se caracterizan por poseer volva castaña grisácea y superficie del píleo fibrillosa mientras que la última se caracteriza por su volva blanca grisácea y superficie del píleo glabra a muy delicadamente fibrillosa. Se registra por primera vez para Argentina a V. taylorii y se amplía el área de distribución de V. subxerophytica para el sector oriental de la región chaqueña. Es importante destacar que V. subxerophytica era conocida sólo por el material tipo y mediante los nuevos ejemplares hallados fue posible mejorar la descripción original. Palabras clave: Agaricomycetes, Fungi, taxonomía, V. subxerophytica, V. taylorii. AbstractThree species of Volvariella from Northern Argentina are illustrated and described. Volvariella taylorii, known from the Yungas and the Paranaense Rain Forests; V. subxerophytica, known exclusively from the xerophytic forest from "chaqueña" region, and V. pusilla which was found in Chaco and Tucumán provinces. The two former species are characterized by having brownish-grayish volva and the fibrillose pileus, and the later by its whitish-grayish volva and the finely and delicately fibrillose surface of the pileus. Volvariella taylorii is recorded for the first time from Argentina and the area of distribution of V. subxerophytica is expanded towards the oriental area of the "chaqueña" region. It is important to mention that V. subxerophytica was only known by the type material and that in this work the original description is improved with data obtained from new specimens.