Mycosphaerangium and Neomelanconium (Cenangiaceae) are closest relatives: phylogenetic relationships, morphology and a new species.

Based on molecular phylogenetic analyses of a multigene matrix of partial nuSSU-ITS-LSU rDNA, RPB1, RPB2 and TEF1 sequences and by morphological evidence, the genus Mycosphaerangium is shown to be the closest relative of Neomelanconium, and confirmed to be a member of the Cenangiaceae (Leotiomycetes). While Mycosphaerangium and Neomelanconium share many traits like similar conidia, conidiogenesis, asci and ascospores, their apothecia differ particularly in excipular features and are therefore recognized as distinct genera. Mycosphaerangium tiliae, described from North America, is excluded from the genus but shown to represent the sexual morph of the European Neomelanconium gelatosporum, and it is therefore synonymized with the latter. Based on morphology, Neomelanconium deightonii is assumed to be congeneric with Neomelanconium gelatosporum, and it is lectotypified. Dermatea tetraspora and Phaeangium magnisporum, the basionyms of Mycosphaerangium tetrasporum and M. magnisporum, respectively, are lectotypified as well, and for M. tetrasporum, the asexual morph is recorded for the first time. Mycosphaerangium quercinum sp. nov. is described as a new species from various Quercus hosts in Europe, where it is shown to be widely distributed. It morphologically and ecologically closely resembles the North American M. tetrasporum, but differs in paraphysis and ascospore morphology and by croziers at its ascus base. The three accepted species of Mycosphaerangium and the two of Neomelanconium are described and illustrated. Mycosphaerangium magnisporum, M. quercinum and M. tetrasporum are recorded to be constantly associated with species of Coryneum, indicating a fungicolous habit, but no evidence for fungal associations has been found in Neomelanconium deightonii and N. gelatosporum.

Two new species of Thyronectria from Mediterranean Europe.

Two new species of Thyronectria growing in Mediterranean vegetation are described from southern Spain; they are T. giennensis from Quercus ilex ssp. rotundifolia and T. pistaciae from Pistacia lentiscus. Both species are characterized by morphology of sexual and asexual morphs and by DNA data. They have olivaceous to green-brown muriform ascospores and are closely related to T. asturiensis and T. roseovirens, as determined by multigene phylogenetic analyses of a matrix containing six loci (ITS and 28S regions of nuc rDNA, ACT1, RPB1, RPB2, TEF1 and TUB2 genes). We also report that Cucurbitaria bicolor is a synonym of Thyronectria rhodochlora, the type species of Thyronectria.

Taxonomic position of the genus Bicornispora and the appearance of a new species Bicornispora seditiosa.

The discovery of a second species of Bicornispora in Spain, B. seditiosa, which is closely related to B. exophiala but has smaller ascospores, narrower asci and different ecology, gave us the opportunity to culture and sequence the fungus. Phylogenetic analyses of rDNA regions including partial nuc 28S rDNA (28S) and ITS1-5.8S-ITS2 (ITS) supported a close relationship with species of the genus Lambertella (Rutstroemiaceae), placing Bicornispora, previously ascribed to Coryneliales, within Helotiales. This result confirmed an evolutionary linkage between certain inoperculate discomycetes such as Lambertella palmeri and derived cleistothecial forms (Bicornispora spp.). Based on analyses of morphological study and molecular phylogenetic analyses, a new combination Rutstroemia asphodeli is proposed for Ciboria asphodeli.

Patterns of commercial fish landings in the Loreto region (Peruvian Amazon) between 1984 and 2006.

Patterns of commercial fish catches over the period from 1984 to 2006 were studied in the Loreto region and in Iquitos, which is the most important town of the region and the principal fish marketplace of the Peruvian Amazon. Despite important inter-annual variations, the overall fish landings have significantly increased in the region during this period. The same three species dominated the catches during the whole period (Prochilodus nigricans, Potamorhina altamazonica and Psectrogaster amazonica), making up about 62% of the catches. However, the number of species exploited by commercial fisheries increased considerably during the 22 years of this study (from about 21 species in 1984 to over 65 in 2006), although part of the difference may be accounted for by a better identification of individual species nowadays. At the same time, the large high-valued species, such as Arapaima gigas, Colossoma macropomum and Brachyplatystoma rousseauxii, declined significantly and were replaced by smaller, short-lived and lower-valued species. Catches of the silver Arahuana (Osteoglossum bicirrhosum) also declined significantly during the studied period, strengthening recent warnings about the species' conservation status (Moreau and Coomes, Oryx 40:152-160, 2006). The relative proportions of the trophic groups (detritivores, omnivores and piscivores) remained relatively constant over the study period, but there were significant changes in the relative abundances of the species groups. The proportion of the dominant group, the Characiformes, which averaged about 81% of the catches, increased between 1984 and 2006, whereas the proportion of the Siluriformes and Perciformes remained constant. On the other hand, the proportion of Osteoglossiformes, represented only by two well known species (Arapaima gigas and Osteoglossum bicirrhosum), declined sharply during the same period. Important differences were observed between the landings of Iquitos and the landing of the whole Loreto region, indicating that conclusions drawn from the study of the Iquitos landings cannot be extrapolated to the whole landings of the Loreto region. The most important difference was the decreasing fish landings in Iquitos, whereas the total landings increased in the Loreto region at the same time. Potential causes of this phenomenon are discussed. Decreasing fish abundance around Iquitos (because of a higher fishing pressure) and a behavioural adaptation of fishermen to better law enforcement in Iquitos are likely explanations to be further investigated.

Gender determination in the Paiche or Pirarucu (Arapaima gigas) using plasma vitellogenin, 17beta-estradiol, and 11-ketotestosterone levels.

Arapaima gigas is an air-breathing giant fish of Amazonian rivers. Given its great economic and cultural importance, the aquaculture development of this species represents an evident solution to face the decline of wild populations. In captivity, reproduction occurs generally in large earthen ponds where stocks of a few tens of brooders are maintained together at the beginning of the rainy season (December-March in the Peruvian Amazon). Fry production relies on the spontaneous formation of male and female pairs, which build a nest, delimit a territory and guard the offspring for at least 20 days from other congeners and predators. However, as sex determination of A. gigas is not possible by morphological criteria, it is very difficult to optimize reproduction conditions and fry production in each pond, which seriously hampers the culture of this species. This situation prompted us to develop sexing methodologies based on (1) the detection of female specific plasma Vitellogenin (Vtg) using an enzyme immuno assay (EIA), and (2) the determination of plasma 17beta-estradiol and 11-ketotestosterone levels for immature specimens. The Vtg purification was performed by electro-elution after polyacrilamide gel electrophoresis (PAGE) from plasma of 17beta-estradiol treated A. gigas juveniles. Two different Vtg molecules were isolated, (Vtg(1) and Vtg(2)) with 184 and 112 kDa apparent molecular masses, respectively, and two antibodies were raised in rabbits for each Vtg molecule. Adult fish were 100% accurately sexed by Vtg EIA, while 100% of immature fish and 95% of adults were accurately sexed by 17beta-Estradiol and 11-Ketestosterone ratios. We also observed different color pattern development in male and female adult fish (6-year-olds) around the reproductive period.