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1.
Ecol Appl ; 33(2): e2773, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36317855

RESUMO

In the welcome circumstance that species believed extinct are rediscovered, it is often the case that biological knowledge acquired before the presumed extinction is limited. Efforts to address these knowledge gaps, in particular to assess the taxonomic integrity and conservation status of such species, can be hampered by a lack of genetic data and scarcity of samples in museum collections. Here, we present a proof-of-concept case study based on a multidisciplinary data evaluation approach to tackle such problems. The approach was developed after the rediscovery, 40 years after its presumed extinction, of the enigmatic Lake Constance deep-water charr Salvelinus profundus. Targeted surveys led to the capture of further species and additional sympatric normal charr, Salvelinus cf. umbla. Since the lake had been subject to massive stocking in the past, an evaluation of the genetic integrity of both extant forms was called for in order to assess possible introgression. A two-step genomic approach was developed based on restriction site associated DNA (RAD). Diagnostic population genomic (single nucleotide polymorphism [SNP]) data were harvested from contemporary samples and used for RNA bait design to perform target capture in DNA libraries of archival scale material, enabling a comparison between extant and historic samples. Furthermore, life history traits and morphological data for both extant forms were gathered and compared with historical data from the past 60-120 years. While extant deep-water charr matched historical deep-water specimens in body shape, gill raker count, and growth rates, significant differences were discovered between historical and extant normal charr. These resulted were supported by genomic analyses of contemporary samples, revealing the two extant forms to be highly divergent. The results of population assignment tests suggest that the endemic deep-water charr persisted in Lake Constance during the eutrophic phase, but not one of the historical genomic samples could be assigned to the extant normal charr taxon. Stocking with non-endemic charr seems to be the most likely reason for these changes. This proof-of-concept study presents a multidisciplinary data evaluation approach that simultaneously tests population genomic integrity and addresses some of the conservation issues arising from rediscovery of a species characterized by limited data availability.


Assuntos
Lagos , Truta , Animais , Efeitos Antropogênicos , Água
2.
J Fish Biol ; 102(1): 4-26, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36444901

RESUMO

A new species, Parakneria alytogrammus, is described from the main stream of the Upper Lufira River. This species is easily distinguished from its congeners from the Congo Basin by its unique colouration, consisting of a low number of transversal bands on each of the caudal-fin lobes, 2 (vs. 3-5) and the presence of an uninterrupted lateral mid-longitudinal black band in fresh and preserved specimens (vs. absent). In addition, the new species differs from its Upper Lualaba congeners by the narrow width of its pectoral-fin base, 4.8-5.6% LS [vs. wider, 8.2-10.1% for P. lufirae, 8.6% LS for P. damasi (holotype), and 7.6-7.9% LS for P. thysi]. Finally, it differs from the only species currently known from the Luapula-Mweru system, P. malaissei, by having a short post-dorsal distance, 36.4-36.6% LS (vs. longer, 38.6-41.1% LS ) and a short post-pelvic distance of 40.0-40.6% LS (vs. longer, 41.4-44.1% LS ). Mitochondrial DNA-haplotypes of P. alytogrammus sp. nov. form a clade, which is sister to the P. thysi clade, and from which it diverges by a genetic (Kimura 2-parameter and uncorrected p) distance of 0.7% in the COI-barcoding locus. The Upper Lufira, one of the sub-basins of the Upper Congo Basin, remains poorly explored relative to its fish fauna. In contrast, the region is well explored with regard to its mineral wealth. Unfortunately, mining exploitation is carried out in the region without proper concern for the environment. Thus, the discovery of this new species for science calls for increased protection and aquatic biodiversity exploration in this mining region.


Assuntos
Código de Barras de DNA Taxonômico , Peixes , Animais , República Democrática do Congo , Peixes/genética , Biodiversidade
3.
J Fish Biol ; 101(5): 1333-1342, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36053860

RESUMO

The small cyprinid genus Prolabeops Schultz, 1941 is restricted to the Nyong and Sanaga River systems in Cameroon. In the past, the genus had been suggested to be either a member of the Labeoninae, Torinae or the Smiliogastrinae mainly on the basis of morphological similarities, and it is nowadays considered as incertae sedis within the Cypriniformes. This study provides the first attempt to reveal the phylogenetic position of Prolabeops using molecular data. For this purpose, the authors sequenced a large fraction of the mitochondrial genome (c. 13,600 bp), including all mitochondrial protein coding genes, of two Prolabeops melanhypopterus specimens and an additional four Enteromius specimens. The large-scale phylogenetic analysis was based on an alignment including all mitochondrial protein coding genes of 902 specimens representing c. 899 cypriniform species. Prolabeops was clearly recovered within the African Smiliogastrinae, forming a weakly supported clade together with Enteromius jae, Enteromius hulstaerti and Barboides gracilis. The study data underline the urgent need of a thorough taxonomic revision of the small African barbs collectively placed in the genus Enteromius.


Assuntos
Cyprinidae , Cipriniformes , Genoma Mitocondrial , Animais , Filogenia , Cipriniformes/genética , Cyprinidae/anatomia & histologia , Proteínas Mitocondriais/genética
4.
J Fish Biol ; 100(5): 1171-1186, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35184288

RESUMO

Several hundred catfish species (order: Siluriformes) belonging to 11 families inhabit Africa, of which at least six families are endemic to the continent. Although four of those families are well-known to belong to the 'Big-Africa clade', no previous study has addressed the phylogenetic placement of the endemic African catfish family Austroglanididae in a comprehensive framework with molecular data. Furthermore, interrelationships within the 'Big-Africa clade', including the most diverse family Mochokidae, remain unclear. This study was therefore designed to help reconstruct inter- and intrarelationships of all currently valid mochokid genera, to infer their position within the 'Big Africa clade' and to establish a first molecular phylogenetic hypothesis of the relationships of the enigmatic Austroglanididae within the Siluriformes. We assembled a comprehensive mitogenomic dataset comprising all protein coding genes and representing almost all recognized catfish families (N = 33 of 39) with carefully selected species (N = 239). We recovered the monophyly of the previously identified multifamily clades 'Big Asia' and 'Big Africa' and determined Austroglanididae to be closely related to Pangasiidae, Ictaluroidea and Ariidae. Mochokidae was recovered as the sister group to a clade encompassing Auchenoglanididae, Claroteidae, Malapteruridae and the African Schilbeidae, albeit with low statistical support. The two mochokid subfamilies Mochokinae and Chiloglanidinae as well as the chiloglanid tribe Atopochilini were recovered as reciprocally monophyletic. The genus Acanthocleithron forms the sister group of all remaining Mochokinae, although with low support. The genus Atopodontus is the sister group of all remaining Atopochilini. In contrast to morphological reconstructions, the monophyly of the genus Chiloglanis was strongly supported in our analysis, with Chiloglanis macropterus nested within a Chiloglanis sublineage encompassing only other taxa from the Congo drainage. This is an important result because the phylogenetic relationships of C. macropterus have been controversial in the past, and because we and other researchers assumed that this species would be resolved as sister to most or all other members of Chiloglanis. The apparent paraphyly of Synodontis with respect to Microsynodontis provided an additional surprise, with Synodontis punu turning out to be the sister group of the latter genus.


Assuntos
Peixes-Gato , África , Animais , Ásia , Congo , Filogenia , Análise de Sequência de DNA
5.
Mol Phylogenet Evol ; 136: 215-226, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30974200

RESUMO

Although the majority of cichlid diversity occurs in the African Great Lakes, these fish have also diversified across the African continent. Such continental radiations, occurring in both rivers and lakes have received far less attention than lacustrine radiations despite some members, such as the oreochromine cichlids (commonly referred to as 'tilapia'), having significant scientific and socio-economic importance both within and beyond their native range. Unique among cichlids, several species of the genus Oreochromis exhibit adaptation to soda conditions (including tolerance to elevated temperatures and salinity), which are of interest from evolutionary biology research and aquaculture perspectives. Questions remain regarding the factors facilitating the diversification of this group, which to date have not been addressed within a phylogenetic framework. Here we present the first comprehensive (32/37 described species) multi-marker molecular phylogeny of Oreochromis and closely related Alcolapia, based on mitochondrial (1583 bp) and nuclear (3092 bp) sequence data. We show widespread discordance between nuclear DNA and mitochondrial DNA trees. This could be the result of incomplete lineage sorting and/or introgression in mitochondrial loci, although we did not find a strong signal for the latter. Based on our nuclear phylogeny we demonstrate that adaptation to adverse conditions (elevated salinity, temperature, or alkalinity) has occurred multiple times within Oreochromis, but that adaptation to extreme (soda) conditions (high salinity, temperature, and alkalinity) has likely arisen once in the lineage leading to O. amphimelas and Alcolapia. We also show Alcolapia is nested within Oreochromis, which is in agreement with previous studies, and here revise the taxonomy to synonymise the genus in Oreochromis, retaining the designation as subgenus Oreochromis (Alcolapia).


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Núcleo Celular/genética , Ciclídeos/classificação , Ciclídeos/genética , DNA Mitocondrial/genética , Filogenia , Adaptação Fisiológica/genética , Animais , Teorema de Bayes , Hibridização Genética , Lagos
6.
Mol Phylogenet Evol ; 124: 82-99, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29477383

RESUMO

Phylogenetic studies focusing on Salmonidae have revealed significant obstacles in trying to clarify some interspecific relationships within the Salmoninae subfamily, due to a limited number of markers typed, conflicting phylogenetic signals and ancient hybridization events. To infer reliable phylogenetic relationships, evaluate several putative scenarios of ancient hybridization, and estimate divergence times within Salmoninae, we applied restriction-site associated DNA sequencing (RAD-seq) to 43 samples, including 26 genetic lineages across 21 species, largely representing the subfamily, with an emphasis on the genus Salvelinus. We identified 28,402 loci and 28,363 putatively unlinked SNPs, which were used in downstream analyses. Using an iterative k-means partitioned dataset and a Maximum Likelihood approach; we generated a well-supported phylogeny, providing clear answers to several previous phylogenetic uncertainties. We detected several significant introgression signals, presumably ancient, in the genus Salvelinus. The most recent common ancestor of Salmonidae dates back to approximately 58.9MY ago (50.8-64 MY) and the crown age of Salmoninae was estimated to be 37.7 MY (35.2-40.8 MY) using a Bayesian molecular dating analysis with a relaxed molecular clock. The divergence among genera of the subfamily occurred between the late Eocene and middle of the Miocene (≈38-11 MY) such as the divergence between the genus Oncorhynchus and Salvelinus, which we estimated to 21.2 MY ago (95% HPD: 19.8-23.0 MY), while species diversification took place mainly during the Neogene (≈22-1.5 MY), with more than half of these events occurring in the last 10 MY.


Assuntos
Variação Genética , Hibridização Genética , Filogenia , Mapeamento por Restrição , Salmonidae/classificação , Salmonidae/genética , Análise de Sequência de DNA/métodos , Animais , Sequência de Bases , Teorema de Bayes , Calibragem , Análise de Dados , Fósseis , Funções Verossimilhança , Fatores de Tempo
7.
Proc Biol Sci ; 283(1822)2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26763702

RESUMO

Strong disruptive ecological selection can initiate speciation, even in the absence of physical isolation of diverging populations. Species evolving under disruptive ecological selection are expected to be ecologically distinct but, at least initially, genetically weakly differentiated. Strong selection and the associated fitness advantages of narrowly adapted individuals, coupled with assortative mating, are predicted to overcome the homogenizing effects of gene flow. Theoretical plausibility is, however, contrasted by limited evidence for the existence of rugged adaptive landscapes in nature. We found evidence for multiple, disruptive ecological selection regimes that have promoted divergence in the sympatric, incipient radiation of 'sharpfin' sailfin silverside fishes in ancient Lake Matano (Sulawesi, Indonesia). Various modes of ecological specialization have led to adaptive morphological differences between the species, and differently adapted morphs display significant but incomplete reproductive isolation. Individual fitness and variation in morphological key characters show that disruptive selection shapes a rugged adaptive landscape in this small but complex incipient lake fish radiation.


Assuntos
Adaptação Biológica , Peixes/fisiologia , Animais , Ecossistema , Comportamento Alimentar , Peixes/anatomia & histologia , Peixes/genética , Especiação Genética , Variação Genética , Geografia , Indonésia , Fenótipo , Seleção Genética
8.
BMC Evol Biol ; 14: 94, 2014 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-24886257

RESUMO

BACKGROUND: The Malili Lakes system in central Sulawesi (Indonesia) is a hotspot of freshwater biodiversity in the Wallacea, characterized by endemic species flocks like the sailfin silversides (Teleostei: Atherinomorpha: Telmatherinidae) radiation. Phylogenetic reconstructions of these freshwater fishes have previously revealed two Lake Matano Telmatherina lineages (sharpfins and roundfins) forming an ancient monophyletic group, which is however masked by introgressive hybridization of sharpfins with riverine populations. The present study uses mitochondrial data, newly included taxa, and different external calibration points, to estimate the age of speciation and hybridization processes, and to test for phylogeographic relationships between Kalyptatherina from ancient islands off New Guinea, Marosatherina from SW Sulawesi, and the Malili Lakes flock. RESULTS: Contrary to previous expectations, Kalyptatherina is the closest relative to the Malili Lakes Telmatherinidae, and Marosatherina is the sister to this clade. Palaeogeographic reconstructions of Sulawesi suggest that the closer relationship of the Malili Lakes radiation to Kalyptatherina might be explained by a 'terrane-rafting' scenario, while proto-Marosatherina might have colonized Sulawesi by marine dispersal. The most plausible analysis conducted here implies an age of c. 1.9 My for the onset of divergence between the two major clades endemic to Lake Matano. Diversification within both lineages is apparently considerably more recent (c. 1.0 My); stream haplotypes present in the sharpfins are of even more recent origin (c. 0.4 My). CONCLUSIONS: Sulawesi's Telmatherinidae have most likely originated in the Sahul Shelf area, have possibly reached the island by both, marine dispersal and island/terrane-rafting, and have colonized the Malili Lakes system from rivers. Estimates for the split between the epibenthic sharpfins and the predominantly pelagic to benthopelagic roundfins in Lake Matano widely coincide with geological age estimates of this rift lake. Diversification within both clades clearly predates hybridization events with stream populations. For Lake Matano, these results support a scenario of initial benthic-pelagic divergence after colonization of the lake by riverine populations, followed by rapid radiation within both clades within the last 1 My. Secondary hybridization of stream populations with the sharpfins occurred more recently, and has thus most likely not contributed to the initial divergence of this benthic species flock.


Assuntos
Peixes/classificação , Peixes/genética , Lagos , Animais , Biodiversidade , Especiação Genética , Hibridização Genética , Indonésia , Nova Guiné , Filogeografia
9.
Mol Phylogenet Evol ; 68(1): 64-80, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23542002

RESUMO

African cichlids formerly referred to as "Tilapia" represent a paraphyletic species assemblage belonging to the so called haplotilapiine lineage which gave rise to the spectacular East African cichlid radiations (EARs) as well as to globally important aquaculture species. We present a comprehensive molecular phylogeny of representative haplotilapiine cichlids, combining in one data set four mitochondrial and five nuclear loci for 76 species, and compare it with phylogenetic information of a second data set of 378 mitochondrial ND2 haplotypes representing almost all important "Tilapia" or Tilapia-related lineages as well as most EAR lineages. The monophyly of haplotilapiines is supported, as is the nested sister group relationship of Etia and mouthbrooding tilapiines with the remaining haplotilapiines. The latter are consistently placed in eight monophyletic clades over all datasets and analyses, but several dichotomous phylogenetic relationships appear compromised by cytonuclear discordant phylogenetic signal. Based on these results as well as on extensive morphological evidence we propose a novel generic and suprageneric classification including a (re-)diagnosis of 20 haplotilapiine cichlid genera and nine tribes. New tribes are provided for the former subgenera Coptodon Gervais, 1853, HeterotilapiaRegan, 1920 and PelmatolapiaThys van den Audenaerde, 1969, in addition for "Tilapia" joka, Tilapia sensu stricto and Chilochromis, Etia, Steatocranus sensu stricto, the mouthbrooding tilapiines and for a clade of West African tilapiines.


Assuntos
DNA Mitocondrial/classificação , NADH Desidrogenase/classificação , Proteínas Nucleares/classificação , RNA Ribossômico 16S/classificação , Tilápia/classificação , África Oriental , África Ocidental , Animais , Núcleo Celular/química , Núcleo Celular/genética , DNA Mitocondrial/genética , Especiação Genética , Mitocôndrias/química , Mitocôndrias/genética , NADH Desidrogenase/genética , Proteínas Nucleares/genética , Filogenia , Filogeografia , RNA Ribossômico 16S/genética , Tilápia/genética
10.
Zootaxa ; 3701: 35-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26191569

RESUMO

Three new species of the lampeye genus Hylopanchax are described from the central Congo basin: H. leki, new species, H. ndeko, new species, and H. moke, new species. These differ considerably in body shape from the two previously de- scribed species, H. stictopleuron and H. silvestris, with two deep bodied and one small and slender species. A redefinition of the diagnostic characters of the genus Hylopanchax is presented, including pronounced sexual dimorphism.


Assuntos
Ciprinodontiformes/anatomia & histologia , Ciprinodontiformes/classificação , África Central , Animais , Feminino , Masculino , Especificidade da Espécie
11.
Ecol Evol ; 12(9): e9300, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36177146

RESUMO

Freshwater habitats of the Caucasus biodiversity hotspot represent a center of endemism for the gobiid genus Ponticola Iljin, 1927. Hitherto, large-scale molecular studies, owing to restricted taxon and geographical sampling, have failed to give an elaborate picture of diversity and evolutionary history of these species. Here, to contribute to filling this gap, we assessed taxonomic diversity, phylogeography and evolutionary history for the south Caspian populations of Ponticola presently classified as P. iranicus and P. patimari, using an integrative taxonomic approach comprising an entire geographic range sampling, and analyses of mitochondrial DNA haplotypes, the head lateral line system, otolith shape, and meristic and morphometric variation. All freshwater samples of the P. syrman group belong to a monophyletic clade with two main subclades: a small subclade confined to the upper Sefidroud sub-basin including the type locality of P. iranicus and a large subclade with three geographically constrained haplogroups (Hg1, Hg2, and Hg3), comprising the rest of the distribution. Hg1 showed an eastern distribution including the type locality of P. patimari, while Hg2 and Hg3 are sister groups with central and western-central distributions, respectively. The freshwater clade diverged from P. syrman during the Tyurkyanian low stand (~150 m b.s.l. lasting ~0.1 Myr), while the divergence of P. iranicus and P. patimari and radiations within P. patimari took place during the Bakunian high stand (up to 50 m a.s.l. lasting ~378-480 kya). Species delimitation analyses indicated two distinct species, corresponding to each main subclade. Although the otolith shape and lateral line analyses did not reflect with phylogeographic pattern, PCA and DFA plots of meristic and morphometric data showed a clear separation of the two major subclades corresponding to P. iranicus and P. patimari, suggesting the presence of significant morphological variation meriting formal taxonomic recognition. Overall, our findings (i) reveal the presence of two freshwater endemic species in the P. syrman group, and pending further investigation, hypothesize the presence of a third cryptic species; (ii) revise and document a narrow distributional range and low diversity for P. iranicus, in contrast to a wider distributional range and high diversity for P. patimari; (iii) suggest that the climatic oscillations of the Pleistocene were associated with the cladogenesis within the P. syrman group; and (iv) allowed for the recognition of conservation units and proposition of management measures.

12.
Zootaxa ; 5154(4): 401-430, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-36095612

RESUMO

Ponticola hircaniaensis sp. nov. is described as a new gobiid species from the Kaboudval Stream, southern Caspian Sea basin. The new species is diagnosed among Caspian Sea basin Ponticola species by the following combination of characters: second dorsal-fin branched rays 1416, anal-fin branched rays 1012, scales in lateral series 5259; lower jaw slightly, if at all, prognathous; head and body yellowish brown showing a reticulate brown pattern on a yellow background, first dorsal fin with a marginal bright orangish-yellow band and a dark anterior spot, upper part of pectoral-fin base with a distinct dark brown stripe; length of third spine in first dorsal fin 13.418.3 % of standard length (SL), second dorsal-fin spine length 11.113.8 % SL, caudal peduncle length and depth 16.420.1 % and 11.112.8 % SL, respectively, head depth at nape 70.981.0 % of head length (HL), and at eye 52.566.0 % HL; sagittal otolith dorsal rim with a broad concavity in the middle, dorsal depression absent or indistinct, sulcus length/sulcus height and sulcus height/otolith height ratios 1.471.82 and 0.340.40, respectively. It is also characterised by a K2P nearest neighbour distance of 5% to P. kessleri in the mtDNA COI barcode region. Mitochondrial and nuclear DNA analyses suggested extensive hybridization between P. hircaniaensis sp. nov. and P. gorlap at Kaboudval, providing evidence for the first record of hybridization in the Ponto-Caspian gobiids. Based on narrow geographic range isolated above the Zarrin Gol Dam (< 2 km2), extensive hybridization with P. gorlap, and other threats, the new species should be considered Critically Endangered.


Assuntos
Perciformes , Animais , Mar Cáspio , Peixes , Hibridização Genética , Rios
13.
Zootaxa ; 5190(2): 151-193, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37045174

RESUMO

An evidence-based annotated checklist of gobiid species (Teleostei: Gobiidae) inhabiting the South Caspian Sea and its catchment area (i.e., the South Caspian Sea sub-basin) is compiled. The South Caspian Sea sub-basin gobiofauna currently comprises 38 confirmed species in 11 genera (i.e., 88.4% of the Caspian gobiofauna); the most diverse genus is Benthophilus (16 species, 42.1%), followed by Ponticola (seven species, 18.4%), and Neogobius (four species, 10.5%). Ten species (26.3%) are endemic to the South Caspian Sea sub-basin, another 21 species (55.3%) are endemic in the Caspian Sea basin as a whole, six (15.8%) are native to the Ponto-Caspian region, and one species (2.6%) is exotic. According to the current IUCN Red List, 24 species (64.9%) are listed as being of "Least Concern", eight species (21.6%) are "Data Deficient", and five species (13.5%) as "Not Evaluated". Similar numbers of species are confirmed to inhabit the South Caspian Sea sub-basin waters of the three countries that border it: Iran harbors 25 species (nine genera), Azerbaijan has 28 species (10 genera), and Turkmenistan has 26 species (10 genera). The greatest known diversity of Benthophilus in South Caspian waters occurs in Azerbaijan and Turkmenistan (11 species each), whereas Iranian waters harbor seven species. In comparison, Iran, with six out of eight species (75%), has the greatest diversity of Ponticola known from the Caspian Sea basin. Species richness and endemism of the Caspian Sea gobiid-fauna varies considerably with latitude: the North, Middle and South sub-basins respectively harbor 21, 31, and 37 native species, of which 0, 3, and 10 species are endemic in that sub-basin alone. The high species diversity and endemism of Gobiidae in the South Caspian Sea sub-basin may have resulted from: (i) greater ecological diversity compared to the northern Caspian Sea marine areas (e.g., water depths) that may have led to differential niche adaptation and adaptive radiation in the Benthophilus-Anatirostrum species flock, (ii) lower historical extinction rate compared to Caspian higher latitudes, which had greater exposure to the Pleistocene's extreme climatic changes, (iii) geological history of freshwater habitats in the South Caspian Sea sub-basin that set the speciation and evolutionary stage for the genus Ponticola during these Pleistocene climatic oscillations, (iv) presently less limiting conditions compared to the North Caspian Sea, i.e., higher present winter minimum of water temperature and higher salinity, and (v) Iranian freshwater abundance, variability and habitat diversity. Contemporary gobiid diversity and endemism in the Caspian Sea basin suggests two higher-priority conservation areas: (i) freshwater habitats of the South Caspian Sea region in Iran and Azerbaijan, and (ii) shallow coastal and deep waters of the South and Middle Caspian Sea sub-basins. An identification key is provided for the updated gobiid species from the South Caspian Sea sub-basin.


Assuntos
Peixes , Perciformes , Animais , Mar Cáspio , Água
14.
Zootaxa ; 4980(1): 4563, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34186992

RESUMO

A new gobiid species, Benthophilus persicus sp. nov., is described from the southern Caspian Sea, Iran. The new species is diagnosed by the following character states: dermal fold on cheek well-developed, large, rectangular; chin barbel 1/32/3 of eye diameter; maximum body width 15.122.9% of standard length; mouth width, 36.355.8% of head length; second dorsal fin I+78; origin of anal fin in front of vertical through origin of second dorsal fin; dermal tubercles present on body, clearly larger than granules, with two posterior rows of spinules forming an acute angle, always less than right angle; dorsal row of tubercles complete, 2229; ventral row of tubercles 2225; ventrolateral row of tubercles absent; tubercles not present on temporal and occipital head regions; granules not present on flanks; transversal suborbital row 6i below posterior end of row b; anterior interorbital transversal row pa with one or two papillae and anterior interorbital transversal papilla row pp with two or three papillae; body with 2022 transversal ltm rows starting anteriorly behind pectoral axilla and alternating anteriorly with three longitudinal llm rows.


Assuntos
Perciformes/anatomia & histologia , Perciformes/classificação , Animais , Mar Cáspio , Larva
15.
Mol Phylogenet Evol ; 56(3): 1011-24, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20580847

RESUMO

Nicaraguan Midas cichlids from crater lakes have recently attracted attention as potential model systems for speciation research, but no attempt has been made to comprehensively reconstruct phylogenetic relationships of this highly diverse and recently evolved species complex. We present a first AFLP (2793 loci) and mtDNA based phylogenetic hypothesis including all described and several undescribed species from six crater lakes (Apoyeque, Apoyo, Asososca Leon, Masaya, Tiscapa and Xiloá), the two great Lakes Managua and Nicaragua and the San Juan River. Our analyses demonstrate that the relationships between the Midas cichlid members are complex, and that phylogenetic information from different markers and methods do not always yield congruent results. Nevertheless, monophyly support for crater lake assemblages from Lakes Apoyeque, Apoyo, A. Leon is high as compared to those from L. Xiloá indicating occurrence of sympatric speciation. Further, we demonstrate that a 'three species' concept for the Midas cichlid complex is inapplicable and consequently that an individualized and voucher based approach in speciation research of the Midas cichlid complex is necessary at least as long as there is no comprehensive revision of the species complex available.


Assuntos
Ciclídeos/classificação , Evolução Molecular , Especiação Genética , Filogenia , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Teorema de Bayes , Ciclídeos/anatomia & histologia , Ciclídeos/genética , DNA Mitocondrial/genética , Genótipo , Modelos Genéticos , Nicarágua , Análise de Sequência de DNA
16.
Mol Phylogenet Evol ; 56(3): 905-17, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20457263

RESUMO

Deep-sea Lantern Sharks (Etmopteridae) represent the most speciose family within Dogfish Sharks (Squaliformes). We compiled an extensive DNA dataset to estimate the first molecular phylogeny of the family and to provide node age estimates for the origin and diversification for this enigmatic group. Phylogenetic inferences yielded consistent and well supported hypotheses based on 4685bp of both nuclear (RAG1) and mitochondrial genes (COI, 12S-partial 16S, tRNAVal and tRNAPhe). The monophyletic family Etmopteridae originated in the early Paleocene around the C/T boundary, and split further into four morphologically distinct lineages supporting three of the four extant genera. The exception is Etmopterus which is paraphyletic with respect to Miroscyllium. Subsequent rapid radiation within Etmopterus in the Oligocene/early Miocene was accompanied by divergent evolution of bioluminescent flank markings which morphologically characterize the four lineages. Higher squaliform interrelationships could not be satisfactorily identified, but convergent evolution of bioluminescence in Dalatiidae and Etmopteridae is supported.


Assuntos
Evolução Molecular , Filogenia , Tubarões/genética , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Fósseis , Genes RAG-1 , Funções Verossimilhança , Modelos Genéticos , Alinhamento de Sequência , Análise de Sequência de DNA , Tubarões/classificação
17.
Zootaxa ; 4834(1): zootaxa.4834.1.8, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-33056136

RESUMO

Corcyrogobius pulcher sp. nov. is described from off Île de Ngor, Dakar, Senegal. Corcyrogobius pulcher is distinguished from its two congeners by having the rear edge of the jaws ending posteriorly below mideye, second dorsal fin I/9, pectoral fin rays 17, pelvic fins oval or truncated posteriorly, scales in lateral series 26-27, anterior oculoscapular head canal with pore ß, suborbital row b of sensory papillae anteriorly beginning below vertical of posterior edge of eye, dark vertical caudal bar, branchiostegal membrane without intense dark spot, cheek with two oblique whitish stripes, the first going from the eye downwards and forward to the posterior jaws, the second on the preopercular, alternating with brown oblique stripe going from behind the eye downwards and forward across the cheek. Furthermore, mitochondrial COI-barcoding data unambiguously support the species-level distinctiveness of the three Corcyrogobius species. A key to the species of Corcyrogobius is provided.


Assuntos
Perciformes , Animais , Peixes , Cabeça , Senegal
18.
Zootaxa ; 4718(2): zootaxa.4718.2.3, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32230016

RESUMO

Two monotypic haplochromine cichlid genera (Teleostei: Cichlidae) of the Pseudocrenilabrus group are described from northern Zambia. One new genus is Palaeoplex gen. nov., with Pa. palimpsest sp. nov. as the type species, from the Luongo and Kalungwishi Rivers (Upper Congo drainage, Luapula subdrainage). It is diagnosed by a unique combination of morphological characters: (1) a fully developed infraorbital series without a distinct gap between the lachrymal and second infraorbital bone, (2) fused hypuralia 1+2 and hypuralia 3+4, (3) molariform teeth on the sagittal series of the lower pharyngeal jaw, and (4) a large maximum size. The second new genus, Lufubuchromis gen. nov., with L. relictus sp. nov. as the type species, is restricted to the upper Lufubu River catchment (Upper Congo drainage, Lake Tanganyika subdrainage). It is diagnosed by a unique combination of morphological characters: (1) a fully developed infraorbital series without a distinct gap between the lachrymal and second infraorbital bone, (2) fused hypuralia 1+2 (rarely with a visible suture) and fused hypuralia 3+4, (3) a unique male coloration pattern, i.e. deep crimson red colored areas on the anterior ventral flank parts, chest and belly and on the lower head; remaining parts of flanks and caudal peduncle bluish), and (4) a Pseudocrenilabrus blotch present in both sexes. Both new genera are compared with all remaining taxa of the Pseudocrenilabrus group and with all representatives of all other major haplotilapiine lineages.


Assuntos
Ciclídeos , Animais , Feminino , Lagos , Masculino , Zâmbia
19.
BMC Evol Biol ; 9: 186, 2009 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-19656365

RESUMO

BACKGROUND: For decades cichlid fishes (Perciformes: Cichlidae) of the East African cichlid radiations (Teleostei: Cichlidae) have served as natural experimental subjects for the study of speciation processes and the search for potential speciation key factors. Despite numerous phylogenetic studies dealing with their intragroup relationships, surprisingly little is known about the phylogenetic placement and time of origin of this enigmatic group. We used multilocus DNA-sequence data from five nuclear and four mitochondrial genes and refined divergence time estimates to fill this knowledge gap. RESULTS: In concordance with previous studies, the root of the East African cichlid radiations is nested within the so called "Tilapias", which is a paraphyletic assemblage. For the first time, we clarified tilapiine intragroup relationships and established three new monophyletic groups:"Oreochromini", "Boreotilapiini" and a group with a distribution center in East/Central Africa, the "Austrotilapiini". The latter is the founder lineage of the East African radiations and emerged at the Miocene/Oligocene boundary at about 14 to 26 mya. CONCLUSION: Our results provide the first resolved hypothesis for the phylogenetic placement of the megadiverse East African cichlid radiations as well as for the world's second most important aquaculture species, the Nile Tilapia, Oreochromis niloticus. Our analyses constitute not only a robust basis for African cichlid phylogenetics and systematics, but provide a valid and necessary framework for upcoming comparative phylogenomic studies in evolutionary biology and aquaculture.


Assuntos
Ciclídeos/genética , Evolução Molecular , Especiação Genética , Filogenia , África Oriental , Animais , Teorema de Bayes , Núcleo Celular/genética , Ciclídeos/classificação , DNA Mitocondrial/genética , Funções Verossimilhança , Análise de Sequência de DNA
20.
Zootaxa ; 4651(3): zootaxa.4651.3.6, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31716900

RESUMO

A new genus and species of goby, Gymnesigobius medits sp. nov., is described from the western Mediterranean slope bottoms at the Balearic Islands. The new goby belongs to the Gobius-lineage (Gobiinae). Examination of the single known specimen exhibits a unique combination of morphological characters which could not be fitted to any known genus. Gymnesigobius gen. nov. is morphologically distinguished from all other genera in the Gobius-lineage by the following combination of characters: chin without fold or barbels; mouth terminal with anterior tip above horizontal level of lower eye edge; predorsal area and first dorsal fin base naked; pelvic fin anterior membrane well developed; head with anterior oculoscapular and preopercular canals, posterior oculoscapular canal absent; pores of head canals enlarged, e.g. pores α and ρ larger or of about the same size as interspaces to pore ß; six transverse suborbital rows of sensory papillae, four continuous suborbital rows in front of row b, fifth row divided in three parts but in front of row b, sixth row just as superior part above row b and below pore α; longitudinal suborbital row b barely reaching forward to the vertical from posterior edge of eye. A full description of the new genus and species is provided. The new species, collected at a depth of between 344 and 364 m (mean depth of 354 m), is one of very few gobiid species found at bathyal depths.


Assuntos
Perciformes , Animais , Peixes , Espanha
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