Diatoms from Brazil: the taxa recorded by Christian Gottfried Ehrenberg.
ABSTRACT: The flora of diatoms from Brazil has been studied by several authors from the beginning of the 19(th) up to now. Some of the old lists and descriptions are unknown or have been ignored by Brazilian researchers and the situation of the names cited was not assessed. Here we compiled a list of 101 taxa of diatoms from Brazil registered by Christian Gottfried Ehrenberg during the 19(th) century. We checked the current nomenclatural status of those taxa and lectotypified species from Brazil described by this author. For this, we accessed the Ehrenberg collection in the Museum für Naturkunde, Berlin, Germany, where 11 samples from Brazil studied by Ehrenberg are housed and published in different papers. Using these samples, we found 101 taxa (specific and infraspecific) published by Ehrenberg from Brazil. Five species (Eunotia bidens Ehrenb., Eunotia depressa Ehrenb., Eunotia elephas Ehrenb., Pinnularia microstauron Ehrenb., and Terpsinoe brasiliensis Ehrenb.) were new descriptions and were lectotypified here. The other species cited for Brazil were described initially from other places. However, 23 names were invalid and one illegitimate.
Project description:To comply with the new phylogeny within the Surirellales as supported by molecular and morphological data, re-evaluations and re-combinations of taxa from and within the genera Surirella, Cymatopleura, and Stenopterobia and with the re-established genus Iconella are necessary. Since the African diatom flora is rich with taxa from these genera, especially Iconella, and the authors have studied these taxa recently, describing also new taxa, a preliminary checklist of African Iconella and Surirella is here presented. 94 names are contained on this list. 57 taxa have been transferred to Iconella; 55 taxa were formerly ranked within Surirella and two taxa within Stenopterobia. 10 taxa have stayed within Surirella and six taxa have been transferred from Cymatopleura to Surirella. 20 Surirella and 1 Stenopterobia names are listed which are either unrevised or unrevisable since morphological data is missing. Four names and taxa described by Ehrenberg are here typified. Two had been transferred to Iconella already: Iconella bifrons (Ehrenb.) Ruck & Nakov and Iconella splendida (Ehrenb.) Ruck & Nakov. Two are re-transferred from Cymatopleura to Surirella: Surirella librile (Ehrenb.) Ehrenb. and Surirella undulata (Ehrenb.) Ehrenb.; both taxa are currently known by their younger synonyms: Cymatopleura solea (Bréb.) W. Smith and Cymatopleura elliptica (Bréb. ex Kützing) W. Smith. Lectotypes for Iconella bifrons, I. splendida, Surirella librile, and S. undulata were designated.
Project description:Numerous species of Eunotia Ehrenb., widely distributed in the world flora, prefer acidic, dystrophic or oligotrophic freshwater habitats with low conductivity and usually occur in epiphytic or epilithic hydrotopes. In Ukraine, only 32 species and eight varieties of Eunotia were known until this study. For the first time, 9 more species have been recorded mainly from the Cheremsky Nature Reserve, located in Ukrainian Polissya. New findings include 2 species widely distributed in the world flora on most continents and 7 rare species known from several locations, among them E.genuflexa, E.jarensis and E.ruzickae, which are probably European endemics as they have not been reported from other continents. For the present time in the Cheremsky Nature Reserve, the 20 species recorded here, the highest species richness of Eunotia in Ukraine, bring the total number of Eunotia in Ukraine to 41 species, which comprises only 7% of Eunotia species in the world flora. This is indirect evidence of insufficient investigation of the wetlands in Ukraine where Eunotia usually is represented with high species richness. Several definitions are suggested to describe morphological features that are peculiar to the diatom frustule particular to the Eunotia species. The genus Eunotia possesses a mirror-symmetric, mantle-offset, brevisslit raphe system, which may or may not have terminal raphe fissures. Morphological analysis provided in this study revealed the absence of terminal raphe fissures for many species of Eunotia. Instead, the distal ends of the raphe slits finish on the outer valve surface by funnel holes, sometimes pore-like ones, connected with the helictoglossae. However, in the literature those distal ends of the raphe slits were described erroneously as terminal raphe fissures. For the first time different types of raphe system are grounded. Two species Eunotiaimplicata Nörpel-Schempp et al. in Alles et al. and Eunotiaincisa W. Smith ex Gregory were lectotypified.
Project description:The nomenclatural confusion between the Indian gingers Hedychium villosum Wallich and its variety Hedychium villosum var. tenuiflorum (Wall. ex Voigt) Wall. ex Baker is discussed. Both taxa are lectotypified in order to stabilize the names and contribute towards a resolution of their confusing nomenclatural past. Both taxa are described in detail to aid identification.
Project description:Specimens belonging to the Cymbellaaffinis / Cymbellatumidula / Cymbellaturgidula species complex have many taxonomic problems, due to their high morphological variability and lack of type designations. Fifteen taxon names of this complex, distributed in five species, were re-evaluated concerning their taxonomic status, and lectotypified based on original material. In addition to light microscopy, some material was analyzed by electron microscopy. Four new combinations are proposed in order to reposition infraspecific taxa.
Project description:The Andean genus Xenophyllum (Compositae, Senecioneae) is distributed along the high-Andes from northeastern Colombia to northern Chile and northwestern Argentina, mainly thriving in the paramo and puna ecoregions. It comprises suffruticose plants forming dense mats, hummocks, or clumps of erect stems. They are characterized by displaying involucral bracts fused at the base, supplementary bracts absent, and mostly radiate capitula with white ray corollas, seldom yellow or pink (disciform in one species). Traditionally, Xenophyllum species were treated as members of the genus Werneria, a morphologically close genus that includes rosettiform or scapiform perennial herbs. As currently circumscribed, Xenophyllum mostly differs from Werneria in having elongate stems. Herein, the first modern and comprehensive revision of the genus recognizing twenty-two species and two subspecies is presented. Werneria decumbens is synonymized with X. weddellii, as well as X. fontii with X. humile and X. oscartovarii with X. dactylophyllum. Likewise, four varietal names and two sectional names are proposed as new synonyms. Seven names are lectotypified, the name X. sotarense is epitypified, W. decumbens neotypified, and the supraspecific name W. sect. Integrifoliae Rockh. is typified. The combination X. crassum subsp. orientalecomb. nov. is made. Descriptions and distribution maps are provided for all accepted species, in addition to an identification key. Ten species are illustrated, three of them for the first time.
Project description:A worldwide survey of cercosporoid ascomycete species on hosts of the genus Diospyros (persimmon) with key to the species based on characters in vivo is provided. Special emphasis is placed on species of the genus Pseudocercospora, which are in part also phylogenetically analysed, using a multilocus approach. Species of the latter genus proved to be very diverse, with a remarkable degree of cryptic speciation. Seven new species are described (Pseudocercospora diospyri-japonicae, P. diospyriphila, P. ershadii, P. kakiicola, P. kobayashiana, and P. tesselata), and two new names are introduced [P. kakiigena (? Cylindrosporium kaki, non Pseudocercospora kaki), and Zasmidium diospyri-hispidae (? Passalora diospyri, non Zasmidium diospyri)]. Six taxa are lectotypified (Cercospora atra, C. diospyri, C. diospyri var. ferruginea, C. flexuosa, C. fuliginosa, C. kaki), and Pseudocercospora kaki is epitypified.
Project description:We sequenced mitochondrial genomes from five diverse diatoms (Toxarium undulatum, Psammoneis japonica, Eunotia naegelii, Cylindrotheca closterium, and Nitzschia sp.), chosen to fill important phylogenetic gaps and help us characterize broadscale patterns of mitochondrial genome evolution in diatoms. Although gene content was strongly conserved, intron content varied widely across species. The vast majority of introns were of group II type and were located in the cox1 or rnl genes. Although recurrent intron loss appears to be the principal underlying cause of the sporadic distributions of mitochondrial introns across diatoms, phylogenetic analyses showed that intron distributions superficially consistent with a recurrent-loss model were sometimes more complicated, implicating horizontal transfer as a likely mechanism of intron acquisition as well. It was not clear, however, whether diatoms were the donors or recipients of horizontally transferred introns, highlighting a general challenge in resolving the evolutionary histories of many diatom mitochondrial introns. Although some of these histories may become clearer as more genomes are sampled, high rates of intron loss suggest that the origins of many diatom mitochondrial introns are likely to remain unclear.
Project description:The genus Neocosmospora (Fusarium solani species complex) contains saprobes, plant endophytes and pathogens of major economic significance as well as opportunistic animal pathogens. Advances in biological and phylogenetic species recognition revealed a rich species diversity which has largely remained understudied. Most of the currently recognised species lack formal descriptions and Latin names, while the taxonomic utility of old names is hampered by the lack of nomenclatural type specimens. Therefore, to stabilise the taxonomy and nomenclature of these important taxa, we examined type specimens and representative cultures of several old names by means of morphology and phylogenetic analyses based on rDNA (ITS and LSU), rpb2 and tef1 sequences. Sixty-eight species are accepted in Neocosmospora, 29 of them described herein as new; while 13 new combinations are made. Eleven additional phylogenetic species are recognized, but remain as yet undescribed. Lectotypes are proposed for eight species, seven species are epitypified and two species are neotypified. Notes on an additional 17 doubtful or excluded taxa are provided.
Project description:Taxonomic revision of the tropical Asian species of Solanum revealed two names, Solanum poka Dunal and Solanum graciliflorum Dunal, whose identities were uncertain and whose application has always been tentative. Material collected in Java at the beginning of the 19th century by Jean-Baptiste Leschenault de la Tour and used to describe these taxa has not been found, despite extensive searches in European herbaria. We here stabilise use of these names by comparing herbarium specimens and drawings of original material made by the artist Toussaint François Node-Véran. Detailed descriptions with synonymy, preliminary conservation assessments and specimen citations are provided for both species. Lectotypes are designated for all names (including synonyms) and epitypes designated for Solanum poka and Solanum graciliflorum to stabilise usage.
Project description:The names Werneria melanandra and W. pygmophylla are transferred to the genus Senecio. They belong to the group of the discoid caespitose Andean Senecio, specifically to the subgroup with blackish anthers and style branches and whitish corollas. The recognition of S. digitatus as a distinct species is also discussed. Within the framework of the mentioned group, the names S. casapaltensis and S. macrorrhizus are lectotypified, S. humillimus var. melanolepis is neotypified, an epitype is designated for the name W. melanandra, and nine new synonyms are proposed. An updated comprehensive dichotomous key including all discoid caespitose Senecio species from Bolivia and Peru is provided.