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Ichthyological surveys have traditionally been conducted using whole-specimen, capture-based sampling with varied but conventional fishing gear. Recently, environmental DNA (eDNA) metabarcoding has emerged as a complementary, and possible alternative, approach to whole-specimen methodologies. In the tropics, where much of the diversity remains undescribed, vast reaches continue unexplored, and anthropogenic activities are constant threats; there have been few eDNA attempts for ichthyological inventories. We tested the discriminatory power of eDNA using MiFish primers with existing public reference libraries and compared this with capture-based methods in two distinct ecosystems in the megadiverse Amazon basin. In our study, eDNA provided an accurate snapshot of the fishes at higher taxonomic levels and corroborated its effectiveness to detect specialized fish assemblages. Some flaws in fish metabarcoding studies are routine issues addressed in natural history museums. Thus, by expanding their archives and adopting a series of initiatives linking collection-based research, training and outreach, natural history museums can enable the effective use of eDNA to survey Earth’s hotspots of biodiversity before taxa go extinct. Our project surveying poorly explored rivers and using DNA vouchered archives to build metabarcoding libraries for Neotropical fishes can serve as a model of this protocol.

This study aimed to determine the sensitivity of 61 Botryotinia ricini isolates to the fungicides fluazinam and thiophanate-methyl. The isolates were originated from Goias (n = 3), Maranhao (n = 3), Mato Grosso (n = 12), Minas Gerais (n = 1), Paraiba (n = 8), Rio Grande do Sul (n = 19) and Sao Paulo (n = 15) states. Mycelial discs (6 mm) removed from 5-day-old colonies were transferred to Petri dishes containing potato dextrose agar (PDA) amended with different concentrations of the fungicides. Two perpendicular measurements of the radial growth were taken and used to calculate the percentage of mycelial growth inhibition (PMGI) for each treatment (isolate × fungicide × concentration) in relation to the control. PMGI were used to obtain the effective concentration that inhibits 50 and 95% of the mycelial growth (EC50 and EC95) by means of linear regression. For fluazinam, the EC50 and EC95 (mean ± SD) were 0.1738 ± 0.0802 μg/mL and 0.7938 ± 0.1254 μg/mL, while for thiophanate-methyl, the EC50 and EC95 were 0.3487 ± 0.0963 μg/mL and 1.1325 ± 0.2063 μg/mL, respectively. Both fungicides have high intrinsic toxicity to B. ricini but fluazinam was a more potent growth inhibitor compared to thiophanate-methyl.

Made available in DSpace on 2020-12-10T20:10:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-02-14 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) NSF Center for Scientific Computing (NCC/GridUNESP) at Sao Paulo State University iXingu Project, NSF The family Trichomycteridae is one of the most diverse groups of freshwater catfishes in South and Central America with eight subfamilies, 41 genera and more than 300 valid species. Its members are widely distributed throughout South America, reaching Costa Rica in Central America and are recognized by extraordinary anatomical specializations and trophic diversity. In order to assess the phylogenetic relationships of Trichomycteridae, we collected sequence data from ultraconserved elements (UCEs) of the genome from 141 specimens of Trichomycteridae and 12 outgroup species. We used a concatenated matrix to assess the phylogenetic relationships by Bayesian inference (BI) and maximum likelihood (ML) searches and a coalescent analysis of species trees. The results show a highly resolved phylogeny with broad agreement among the three distinct analyses, providing overwhelming support for the monophyletic status of subfamily Trichomycterinae including Ituglanis and Scleronema. Previous relationship hypotheses among subfamilies are strongly corroborated, such as the sister relationship between Copionodontinae and Trichogeninae forming a sister clade to the remaining trichomycterids and the intrafamilial clade TSVSG (Tridentinae-Stegophilinae-VandelliinaeSarcoglanidinae-Glanapteryginae). Monophyly of Glanapteryginae and Sarcoglanidinae was not supported and the enigmatic Potamoglanis is placed outside Tridentinae. Univ Estadual Paulista, Dept Morfol, Inst Biociencias, Botucatu, SP, Brazil Univ Sao Paulo, Museu Zool, Sao Paulo, SP, Brazil Inst Invest Recursos Biol Alexander von Humboldt, Villa De Leyva, Boyaca, Colombia Drexel Univ, Acad Nat Sci, Philadelphia, PA 19104 USA Univ Calif Los Angeles, Dept Ecol & Evolutionary Biol, Los Angeles, CA USA Univ Estadual Paulista, Dept Morfol, Inst Biociencias, Botucatu, SP, Brazil FAPESP: 2014/26508-3 FAPESP: 2015/13382-4 FAPESP: 2014/06853-8 FAPESP: 2016/19075-9 FAPESP: 2014/05051-5 FAPESP: 2015/00691-9 FAPESP: 2016/11313-8 NSF: DEB 0107751 NSF: DEB-0315963 iXingu Project, NSF: DEB-1257813

Background The facial musculature is a remarkable anatomical complex involved in vital activities of fishes, such as food capture and gill ventilation. The evolution of the facial muscles is largely unknown in most major fish lineages, such as the Actinopterygii. This megadiverse group includes all ray-finned fishes and comprises approximately half of the living vertebrate species. The Polypteriformes, Acipenseriformes, Lepisosteiformes, Amiiformes, Elopiformes, and Hiodontiformes occupy basal positions in the actinopterygian phylogeny and a comparative study of their facial musculature is crucial for understanding the cranial evolution of bony fishes (Osteichthyes) as a whole. Results The facial musculature of basal actinopterygians is revised, redescribed, and analyzed under an evolutionary perspective. We identified twenty main muscle components ontogenetically and evolutionarily derived from three primordial muscles. Homologies of these components are clarified and serve as basis for the proposition of a standardized and unifying myological terminology for all ray-finned fishes. The evolutionary changes in the facial musculature are optimized on the osteichthyan tree and several new synapomorphies are identified for its largest clades, including the Actinopterygii, Neopterygii, and Teleostei. Myological data alone ambiguously support the monophyly of the Holostei. A newly identified specialization constitutes the first unequivocal morphological synapomorphy for the Elopiformes. The myological survey additionally allowed a reinterpretation of the homologies of ossifications in the upper jaw of acipenseriforms. Conclusions The facial musculature proved to be extremely informative for the higher-level phylogeny of bony fishes. These muscles have undergone remarkable changes during the early radiation of ray-finned fishes, with significant implications for the knowledge of the musculoskeletal evolution of both derived actinopterygians and lobe-finned fishes (Sarcopterygii).