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1.
Biodivers Genomes ; 20242024 Apr.
Article in English | MEDLINE | ID: mdl-38698932

ABSTRACT

We present the complete genome sequences of 12 species of Enteromius. Illumina sequencing was performed on genetic material from museum specimens. The reads were assembled using a de novo method followed by a finishing step. The raw and assembled data are publicly available via Genbank.

2.
Zookeys ; 1197: 57-91, 2024.
Article in English | MEDLINE | ID: mdl-38616924

ABSTRACT

The recent surge in the discovery of hidden diversity within rheophilic taxa, particularly in West and East Africa, prompted a closer examination of the extent to which the current taxonomy may obscure the diversity of riffle-dwelling suckermouth catfishes in the genus Chiloglanis in southern Africa. Currently, the region comprises eight valid species within this genus. Seven of them have relatively narrow geographic distribution ranges except for C.neumanni, which is considered to be widely distributed, occurring from the Buzi River system in the south, and its northern limit being the eastward draining river systems in Tanzania. Recent surveys of the middle Zambezi River system revealed Chiloglanis specimens that were distinguishable from the known species of the genus from southern Africa. Integration of molecular and morphological data indicated that these specimens from the Mukwadzi River represent a new species to science, herein described as Chiloglaniscarnatus Mutizwa, Bragança & Chakona, sp. nov. This species is readily distinguished from its southern African congeners by the possession of a distinctive extended dermal tissue covering the base of the dorsal fin and the possession of ten mandibular teeth (vs 8, 12, or 14 in the other taxa). Results from this study add to the growing evidence of a high level of undocumented diversity within riffle-dwelling taxa in southern Africa.

3.
J Inorg Biochem ; 240: 112096, 2023 03.
Article in English | MEDLINE | ID: mdl-36603242

ABSTRACT

The rational design and functionalization of small, simple, and stable peptides scaffolds is an attractive avenue to mimic catalytic metal-centres of complex proteins, relevant for the design of metalloenzymes with environmental, biotechnological and health impacts. The de novo designed α3DIV-L21C framework has a rubredoxin-like metal binding site and was used in this work to incorporate a Mo-atom. Thermostability studies using differential scanning calorimetry showed an increase of 4 °C in the melting temperature of the Mo-α3DIV-L21C when compared to the apo-α3DIV-L21C. Circular dichroism in the visible and far-UV regions corroborated these results showing that Mo incorporation provides stability to the peptide even though there were almost no differences observed in the secondary structure. A formal reduction potential of ∼ -408 mV vs. NHE, pH 7.6 was determined. Combining electrochemical results, EPR and UV-visible data we discuss the oxidation state of the molybdenum centre in Mo-α3DIV-L21C and propose that is mainly in a Mo (VI) oxidation state.


Subject(s)
Metalloproteins , Molybdenum , Molybdenum/chemistry , Rubredoxins/metabolism , Metalloproteins/chemistry , Oxidation-Reduction , Peptides/metabolism
4.
Biodivers Data J ; 11: e98632, 2023.
Article in English | MEDLINE | ID: mdl-38327355

ABSTRACT

Background: The Maranhão State harbours great fish diversity, but some areas are still undersampled or little known, such as the Munim River Basin in the northeast of the State. This lack of knowledge is critical when considering anthropogenic impacts on riverine systems especially in the face of major habitat destruction. These pressing threats mean that a comprehensive understanding of diversity is critical and fish checklists extremely relevant. Therefore, the present study provides a checklist of the fish species found in the Munim River Basin, Maranhão State, north-eastern Brazil, based on collected specimens. New information: A total of 123 species were recorded for the Munim River Basin, with only two non-native species, Oreochromisniloticus and Colossomamacropomum, showing that the fish assemblage has relatively high ecological integrity. In addition, 29 species could not be identified at the species level, indicating the presence of species that are probably new to science in the Basin. A predominance of species belonging to the fish orders Characiformes and Siluriformes, with Characidae being recovered as the most species-rich family (21 species) agrees with the general pattern for river basins in the Neotropical Region. The total fish diversity was estimated by extensive fieldwork, including several sampling gears, carried out in different seasons (dry and rainy) and exploring different environments with both daily and nocturnal sampling, from the Basin's source to its mouth. A total of 84 sites were sampled between 2010 and 2022, resulting in 12 years of fieldwork. Fish assemblages were distinct in the Estuary and Upper river basin sections and more similar in the Lower and Middle sections indicating environmental filtering processes. Species were weakly nested across basin sections, but unique species were found in each section (per Simpsons Index). High variability of species richness in the Middle river basin section is likely due to microhabitat heterogeneity supporting specialist fish communities.

5.
Zool Stud ; 60: e4, 2022.
Article in English | MEDLINE | ID: mdl-35774256

ABSTRACT

The Kryptolebias marmoratus species group is composed of the only three vertebrate species that lack females. These species present only males and simultaneously hermaphroditic individuals; that are able to reproduce by allogamy, with males, or by autogamy, performing self-fertilization and generating clones of themselves. The proportion of males is variable among those species and even among their populations. Kryptolebias hermaphroditus has the smallest proportion of males. Indeed, no males have been recorded in most known populations. This is a mainly autogamous species, with small populations having a disjunct distribution along the eastern and northern coast of Brazil. Species presenting such adaptations would be expected to have an elevated rate of genetic population structure, reflecting any barriers that obstruct gene flow between populations. Partial sequences of the mitochondrial cytochrome c oxidase I (COI) gene from 335 individuals were sampled to perform a population analysis. Only a single haplotype of COI, widely distributed throughout all the sampled populations, was recovered for K. hermaphroditus. Here we hypothesize that the high degree of communication within populations is probably the main biological feature leading to this pattern.

6.
Zootaxa ; 4927(2): zootaxa.4927.2.10, 2021 Feb 12.
Article in English | MEDLINE | ID: mdl-33756715

ABSTRACT

The poeciliid species, Poecilia kempkesi Poeser, 2013, was the fourth species of the subgenus Acanthophacelus Eigenmann, 1907 to be described, based on individuals from a single urban anthropized locality close to Paramaribo, Suriname (Poeser, 2013). The description itself lacked any section clearly distinguishing the new species from the remaining species of Poecilia Bloch Schneider 1801, and in particular from the species of the subgenus Acanthophacelus, type species Poecilia reticulata Peters, 1859. According to Article 13 of the International Code of Zoological Nomenclature (ICZN, 1999) the criteria of availability for a species-group name are:.


Subject(s)
Cyprinodontiformes , Poecilia , Animals
7.
J Fish Biol ; 98(3): 655-667, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33125161

ABSTRACT

Two new species of the lampeye genus Hylopanchax are described from the Ivindo River basin in the Ogowe River drainage. Hylopanchax multisquamatus, new species, and Hylopanchax thysi, new species, differ from congeners by the presence of a hyaline urogenital male papilla with small black spots and a dark-brown reticulate pattern on the flanks of both males and females in preserved specimens. Hylopanchax multisquamatus is distinguished from congeners by the number of scales on the mid-longitudinal series (27-30 vs. 19-26, respectively) and by the relative anterior/posterior flank scale depth ratio (140%-150% vs. 170%-220%). Hylopanchax thysi is distinguished from all other congeners, except Hylopanchax paucisquamatus, by the presence of vertebrae (30 vs. 31-33) and is further distinguished from H. multisquamatus by the presence of a deeper caudal peduncle and much larger anterior flank scales. It is distinguished from H. paucisquamatus by the presence of a hyaline urogenital male papilla with small black spots and a dark-brown reticulate pattern on the flanks of both males and females in preserved specimens. Osteological data of Hylopanchax are presented for the first time, and an updated diagnosis based on external morphology, colouration pattern and osteology is provided. An osteological comparison with closely related species belonging to the genera Procatopus, Hypsopanchax and "Hypsopanchax" is presented. (a) A truncate and slightly downward-directed anterior process of the angulo-articular and (b) a guitar-shaped lachrymal with both its anterior and posterior margins sharply curved are here considered as diagnostic features of Hylopanchax.


Subject(s)
Bone and Bones/anatomy & histology , Cyprinodontiformes/anatomy & histology , Cyprinodontiformes/classification , Pigmentation , Animals , Female , Gabon , Male , Osteology , Rivers , Skin/anatomy & histology , Species Specificity , Specimen Handling , Spine/anatomy & histology
8.
Biota Neotrop. (Online, Ed. ingl.) ; 21(2): e20201172, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1180715

ABSTRACT

Abstract: Recent statements from the Brazilian federal government indicate that impacting economic activities, particularly commercial shrimp farming, are being encouraged in mangrove areas in the near future. Alterations of the National Action Plan and legal instruments that partially protected mangrove ecosystems have created an even weaker legal framework than previously existed. Such changes are leading Brazil far from the global call to conserve mangroves and from the Aichi targets and United Nations Sustainable Development Goals. Unfortunately, the loss of mangrove ecosystems and their ecosystem services will negatively impact living standards for Brazilians in coastal areas.


Resumo: As recentes determinações do governo Brasileiro indicam que atividades econômicas impactantes para os manguezais, particularmente a carcinocultura, serão incentivadas num futuro próximo. Alterações no Plano de Ação Nacional e em outros instrumentos legais, que parcialmente protegiam os manguezais, fragilizaram ainda mais os meios legais para proteção dessas áreas. Essas mudanças fazem o Brasil seguir na contra-mão da demanda global pela conservação dos manguezais e dos objetivos de desenvolvimento sustentável traçados pela Organização das Nações Unidas, bem como das metas de Aichi para a biodiversidade. Consequentemente, a iminente perda dos ecossistemas de manguezais impactará negativamente o padrão de vida dos Brasileiros que vivem em áreas costeiras.

9.
J Fish Biol ; 97(6): 1713-1723, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32914416

ABSTRACT

The present study explored the diversity of Nannocharax within southern Africa by implementing three species delimitation methods for a data set consisting of 37 mitochondrial cytochrome oxidase subunit I sequences. Two unilocus coalescent methods, the General Mixed Yule Coalescent (GMYC) and the Bayesian implementation of the Poisson Tree Processes (bPTP), and a genetic distance method, the Automatic Barcode Gap Discovery (ABGD), were applied. Both GMYC and bPTP delimited the same operational taxonomic units (OTUs), revealing a higher diversity for the genus in the region than previously recognised, whereas the ABGD failed to delimit the same candidate species. All methods delimited two species groups, and these are supported based on colouration patterning and morphology; the Nannocharax multifasciatus and the Nannocharax macropterus species groups and the delimited OTUs were assigned to each. Two putative new species were identified, Nannocharax cf. lineostriatus "Okavango" from the Okavango River in Angola and N. cf. lineostriatus "Kwanza" from the Kwanza River system in Angola. The distribution of Nannocharax dageti was confirmed for the Upper Zambezi and extended to the Okavango system, and an identification key for the southern Africa Nannocharax species is provided.


Subject(s)
Biodiversity , Characiformes/classification , Phylogeny , Africa, Southern , Angola , Animals , Bayes Theorem , DNA Barcoding, Taxonomic/veterinary
10.
RECIIS (Online) ; 14(2): 307-328, abr.-jun. 2020. ilus, graf
Article in Portuguese | LILACS | ID: biblio-1102488

ABSTRACT

O artigo objetiva analisar a cobertura midiática do desastre socioambiental ocorrido em 2018, em Barcarena, no Pará, e discutir tanto as diferenças entre a duração do desastre (prolongada) e a duração da cobertura (concentrada), quanto os direcionamentos de escuta entre a repercussão de eventos gerados por vozes oficiais/institucionais e a presença/ausência de vozes populares de comunidades e movimentos sociais. Como resultado, apresenta três momentos de análise dos dados coletados em clipping nacional ao longo de oito meses: uma análise quantitativa da frequência da cobertura indicando alcance e duração da visibilidade midiática; um recorte quanti-quali apontando como a mídia agenda e promove enquadramento por meio das fontes acionadas na produção da notícia; e uma análise qualitativa, na perspectiva de colonial, de como aparecem na cobertura do desastre as vozes historicamente silenciadas. Para compreender o desastre como processo, busca-se antes situar o contexto da mineração na Amazônia a partir do aporte da Ecologia Política.


The article aims to analyze the media coverage of the socio-environmental disaster that occurred in 2018, in Barcarena, Pará, and to discuss both the differences between the duration of the disaster (prolonged) and the duration of the coverage (concentrated), as well as the listening directions between the repercussion events generated by official/institutional voices and the presence/absence of popular voices from communities and social movements. As a result, it presents three moments of analysis of data collected in national clipping over eight months: a quantitative analysis of the frequency of coverage indicating reach and duration of media visibility; a quanti-quali cut pointing out how the media schedules and promotes framing through the sources used in the production of the news; a qualitative analysis, in the decolonial perspective, of how historically silenced voices appear in the coverage of the disaster. To understand disaster as a process, we first seek to situate the context of mining in the Amazon from the perspective of Political Ecology.


El artículo tiene como objetivo analizar la cobertura mediática del desastre socioambiental ocurrido en 2018, en Barcarena, en Pará, y discutir tanto las diferencias entre la duración del desastre (prolongada) y la duración de la cobertura (concentrada) en cuanto a los direccionamientos de la escucha entre la repercusión de eventos generados por voces oficiales/institucionales y la presencia/ausencia de voces populares de comunidades y movimientos sociales. Como resultado, presenta tres momentos de análisis de los datos recogidos en clipping nacional a lo largo de ocho meses: un análisis cuantitativo de la frecuencia de la cobertura indicando alcance y duración de la visibilidad mediática; un recorte cuanti-quali señalando cómo los medios de comunicación agenda y promueve encuadre a través de las fuentes impulsadas en la producción de las noticias; y un análisis cualitativo, desde la perspectiva decolonial, de cómo aparecen en la cobertura del desastre las voces históricamente silenciadas. Para entender el desastre como proceso se busca, primero, situar el contexto de la minería en la Amazonía a partir del aporte de la Ecología Política.


Subject(s)
Humans , Industrial Disaster , Environmental Pollution , Environmental Journalism , Environmental Communication , Mining , Brazil , Data Collection , Mass Media
11.
Zookeys ; 923: 91-113, 2020.
Article in English | MEDLINE | ID: mdl-32292273

ABSTRACT

Through the analysis of a comprehensive database of COI sequences, with the sequencing of 48 specimens, a first insight into the genetic diversity, distribution and relationships between the southern Africa "Lacustricola" species is presented. Species from "Lacustricola" occur mainly in freshwater systems within the arid savanna, and are considered to be widely distributed in southern Africa, but most of them are data deficient taxa. Two species are redescribed, "Lacustricola" johnstoni (Günther, 1894) and "Lacustricola" myaposae (Boulenger, 1908), based on specimens collected at their respective type localities. Detailed osteological and life colouration information is presented for the first time. "Lacustricola" johnstoni was described from the Upper Shire River in Mangochi, Lake Malawi but is herein considered as widespread in the Okavango, Zambezi, southern Africa east coastal drainages and the Bangweulu in the Congo System. A sympatric similar species occurring in the Okavango is also identified. "Lacustricola" myaposae (Boulenger, 1908), was described from the Nseleni River in KwaZulu-Natal Province, South Africa and is herein considered to be endemic to the small coastal river drainages within this region. Lectotypes for both "L." johnstoni and "L." myaposae are designated. A new species from the Lualaba River in the Congo System, sister to "L." macrurus is identified, and the deep bodied "L." jubbi is considered sister taxon to a clade including "L." johnstoni and "L." myaposae.

12.
J Fish Biol ; 96(5): 1186-1201, 2020 May.
Article in English | MEDLINE | ID: mdl-31038741

ABSTRACT

Based on literature, museum collections and three recent expeditions, an annotated species list of the Lake Edward, East Africa, drainage system is presented, excluding the endemic haplochromines. A total of 34 non-Haplochromis species belonging to 10 families and 21 genera are recorded from the system. Three of these are endemic and two others have been introduced in the region. Six species are new records for the Lake Edward system. A species accumulation curve indicates that we probably covered most of the non-Haplochromis species in the area sampled during the recent expeditions, but undetected species might still be present in the Congolese part of the system, which is poorly sampled. A comparison of the species list with those of neighbouring basins confirmed the placement of the Lake Edward system within the east-coast ichthyofaunal province.


Subject(s)
Fishes/classification , Africa, Eastern , Animals , Biodiversity , Fishes/physiology , Lakes
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