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1.
Zootaxa ; 4588(1): zootaxa.4588.1.1, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31716112

RESUMO

A checklist of the marine and estuarine fishes of New Ireland Province is presented, with special emphasis on Kavieng District, combining both previous and new records. After the recent KAVIENG 2014 expedition, a total of 1325 species in 153 families were recorded from the region. The largest families are the Gobiidae, Pomacentridae, Labridae, Serranidae, Apogonidae, Lutjanidae, Chaetodontidae, Blenniidae, Carangidae, Acanthuridae, Scaridae, Holocentridae, Syn-gnathidae, Lethrinidae and Scorpaenidae. A total of 810 fish species (61.1 % of the total marine and estuarine fish fauna) are recorded from New Ireland for the first time.The fish fauna of New Ireland includes 142 species in transitional waters and 1264 species in marine habitats, and 54 species species in freshwater habitats. Zoogeographically, 1179 species have a wide distribution range, most frequently a broad Indo-West Pacific distribution. Among the remaining species, just 12 are endemic to New Ireland.


Assuntos
Perciformes , Animais , Ecossistema , Oceano Pacífico , Papua Nova Guiné
2.
PeerJ ; 6: e5357, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30128183

RESUMO

We investigated a pantropical sub-family and genus of damselfishes, the sergeant-majors (Pomacentridae: Abudefdufinae: Abudefduf), to identify the tempo and mechanisms of speciation in the lineage. We examined sequence capture data from 500 loci and 20 species, with multiple individuals sampled from across the geographic ranges of widespread species. Utilizing a maximum likelihood framework, as well as a time-calibrated Bayesian phylogeny, the following key questions are addressed: What is the historical tempo of speciation? What are the relative contributions of vicariant, peripatric and parapatric speciation to sergeant-major diversity? How is speciation related to major variation in trophic ecology? The approximately 20 species of sergeant-majors fall into three main lineages. The ancestral condition appears to be benthivory, which is predominant in two lineages comprising six species. The remaining species of sergeant-majors, of which there are at least 15, fall within a clade composed entirely of planktivores. This clade is sister to a benthivore clade that included one species, Abudefduf notatus, in transition to planktivory. Most speciation of sergeant-majors, which appeared ∼24 million years ago, occurred in the last 10 million years. Present distributional patterns indicate vicariant speciation precipitated by the closure of land barriers between both sides of the Atlantic and the Pacific, and the emergence of land between the Indian and Pacific Oceans. Within this backdrop, frequent oscillations in sea level over the last 10 million years also appear to have generated conditions suitable for both peripatric and vicariant speciation, and most speciation within the genus appears linked to these changes in sea level. Diversification within the genus has been concentrated in planktivorous seargeant-majors rather than benthivores. The root cause is unclear, but does not appear to be related to differences in dispersal potential, which is greater in the planktivorous species, due to the ability of their post-larval juveniles to raft with floating debris. This elevated speciation rate in planktivores and their propensity to form local endemics may reflect relaxation of selective pressures (e.g., on crypticity) that limit speciation in benthivorous sergeant-majors. Finally, our data allow us to clarify relationships of geminate sergeant-major species, indicating that there are subdivisions within the Atlantic for both benthivore and planktivore geminate pairs that may have misled previous studies.

3.
Zootaxa ; 4413(2): 271-294, 2018 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-29690109

RESUMO

The freshwater melanotaeniid genus Cairnsichthys is endemic to a relatively small area of specialised habitat within the Wet Tropics bioregion of north-eastern Queensland, Australia. It was previously considered as monotypic, including only a single species, C. rhombosomoides (Nichols Raven, 1928). The recent discovery of an apparently-isolated population in the Daintree rainforest, approximately 120 km north of the known range extent, prompted a detailed investigation of its taxonomic status using a combined lines of evidence approach. We provide compelling evidence from multiple nuclear genetic markers (52 allozyme loci), mitochondrial DNA sequence data (1141 bp cytochrome b) and morphology (examination of a suite of 38 morphometric and meristic characters) that supports north-south splitting of C. rhombosomoides. Accordingly, we describe the northern population as a distinct species, C. bitaeniatus sp. nov., on the basis of 25 specimens, 34.7-65.6 mm SL. The new species differs morphologically primarily by having a more slender and narrow shape, featuring a flatter, straighter predorsal profile and shorter second dorsal fin base; possession of slightly smaller scales, reflected in higher counts of lateral scales and predorsal scales; typically more vertebrae; and colour differences including a more robust, short black stripe across the upper operculum, a pronounced yellow patch on the anteroventral body and usually a more conspicuous second dark stripe on the lower body, with adult males generally having yellowish compared to reddish fins. We also provide a generic diagnosis for Cairnsichthys and a redescription of C. rhombosomoides. Information on the known distribution, habitats and conservation status of species in the genus is summarised, the new species being of particular concern as a narrow range endemic with specific environmental requirements.


Assuntos
Peixes , Distribuição Animal , Animais , Austrália , Ecossistema , Masculino , Queensland
4.
Zootaxa ; 4338(2): 333-340, 2017 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-29245744

RESUMO

The Pseudochromis reticulatus complex is diagnosed to include species of Pseudochromis with the combination of a pointed caudal fin (rounded with middle rays produced), a reticulated colour pattern on the upper part of the body, dorsal-fin rays modally III,26, anal-fin rays modally III,15, and pectoral-fin rays modally 18. Members of the complex include P. reticulatus Gill & Woodland, P. pictus Gill & Randall, P. tonozukai Gill & Allen, P. jace Allen, Gill & Erdmann and P. stellatus new species. The last-named is herein described from six specimens from Batanta and Batu Hitam in the Raja Ampat Islands, West Papua, Indonesia. It is distinguished from other members of the complex in live coloration, and in having higher mean numbers of scales in lateral series and of anterior lateral-line scales (36-38 and 29-32, respectively), and a deeper body as measured from the dorsal-fin origin to pelvic-fin origin (31.8-33.5 % SL).


Assuntos
Peixes , Animais , Cor , Indonésia
5.
Zootaxa ; 3986(2): 201-16, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26250181

RESUMO

Three new species of Glossogobius are described from New Guinea. Glossogobius multipapillus, n. sp. from northeastern New Guinea has a lobed mental fraenum and a distinctive papilla pattern unlike any other species in the genus. Glossogobius sentaniensis, n. sp. is described from Lake Sentani. The species is similar to Glossogobius aureus and G. koragensis differing in head pores and large dark spots on the body. Glossogobius macrocephalus n. sp. from Lake Tebera and surrounding rivers has a lobed mental fraenum and differs from other species in the Glossogobius celebius group in the combination of having a large head, head pore, fin-ray and predorsal scale counts.


Assuntos
Perciformes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Masculino , Nova Guiné , Tamanho do Órgão , Perciformes/anatomia & histologia , Perciformes/crescimento & desenvolvimento
6.
Zootaxa ; 3881(4): 328-40, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25543639

RESUMO

A new species of the cardinalfish genus Siphamia is described from specimens collected in the Province of West Papua, Indonesia, at depths of 50-72 m. Siphamia papuensis n. sp. has a striated light organ which makes it a member of the S. tubifer species group. Within this group it is closely related to S. argentea, sharing with the latter 13 pectoral-fin rays, 9 developed gill rakers and an irregular pattern of yellowish green bars on the body. It differs from S. argentea in having an incomplete lateral line and in lacking dark marks on the head, and at the origin and end of the dorsal-fin and anal-fin bases, as well as the absence of red spots along the light organ and along the back. Japanese records of S. tubulata are reidentified as S. argentea, and new locality records for S. argentea and S. stenotes are reported. Analysis of sequence data from a 16S rDNA fragment revealed the clear separation of S. papuensis n. sp., S. argentea and other included Siphamia species (S. jebbi, S. tubifer and S. stenotes). 


Assuntos
Perciformes/anatomia & histologia , Perciformes/classificação , Distribuição Animal , Animais , Feminino , Indonésia , Masculino , Perciformes/genética , Perciformes/fisiologia , Filogenia , Especificidade da Espécie
7.
Zootaxa ; 3832: 1-247, 2014 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25081275

RESUMO

A checklist of the marine and estuarine fishes of Madang District is presented, combining both previous and new records. After the recent PAPUA NIUGINI 2012 expedition, a total of 1337 species in 129 families have been recorded from the region. One species and one family is not native (Cichlidae: Oreochromis mossambicus), but has been introduced. The native fish fauna of Madang therefore consists of 1336 species in 128 families. The largest families are the Gobiidae, Labridae, Pomacentridae, Apogonidae, Serranidae, Blenniidae, Chaetodontidae, Syngnathidae and Muraenidae, Scorpaenidae and Lutjanidae, Myctophidae, Acanthuridae, Scaridae, Holocentridae, Carangidae, Pomacanthidae and Tetraodontidae, and Caesionidae. A total of 820 fish species (61.4 % of the total marine and estuarine fish fauna) are recorded from Madang for the first time. The fish fauna of Madang includes a total of 187 species of transitional waters and 1326 species in marine habitats. A total of 156 species of the marine or estuarine species also occurs in freshwater. Zoogeographically, 1271 species have a wide distribution range, most frequently a broad Indo-West Pacific distribution. Among the remaining species, only 8 are endemic to Madang District. Anthropogenic threats to the fish fauna and habitats of Madang District include extensive fishing in Madang Lagoon, sometimes with destructive fishing practices; the discharge of untreated sewage of human settlements, mining and industrial developments into the lagoon and nearby oceanic habitats; and destruction of mangrove habitats by extensive construction work on the shores. These anthropogenic threats may call for conservation and monitoring measures in the near future.


Assuntos
Peixes/classificação , Distribuição Animal , Animais , Biodiversidade , Lista de Checagem , Ecossistema , Feminino , Masculino , Papua Nova Guiné
8.
Mol Phylogenet Evol ; 67(1): 15-27, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23313459

RESUMO

The family Melanotaeniidae (rainbowfishes) represents the largest monophyletic group of freshwater fishes found in Australia and New Guinea. The family consists of seven genera and a total of 81 species, which are broadly distributed throughout the region. We conducted a phylogenetic analysis of Melanotaeniidae based on nearly complete taxonomic sampling of all species. We sequenced seven protein coding mitochondrial genes and the first two introns of the nuclear S7 gene, for a total of 6827 base pairs. Our goal was to use the phylogeny to infer the biogeographic history of rainbowfishes in this region, to provide a framework for the timing of divergence within the family, and to test for possible introgression between species. We found strong support for the monophyly of Melanotaeniidae. Three species-poor genera-Cairnsichthys, Rhadinocentrus and Iriatherina-were all resolved as early branching lineages within the family. The three species-rich genera-Melanotaenia, Chilatherina and Glossolepis-did not form a single monophyletic group, but instead formed three monophyletic groups endemic to discrete geographic regions: western New Guinea, northern New Guinea, and southern New Guinea plus Australia, respectively. All three geographic regions also contained three to four additional lineages that were separated by large genetic divergences and were frequently sympatric (except in western New Guinea). Our molecular clock results provide much older estimates of divergence than some aspects of the present geological setting. For instance, the formation of the present day Central Highlands, the integration of the Birds Head region with the rest of New Guinea, and the present proximate position of Waigeo and Batanta islands relative to the Birds Head, are all younger than the rainbowfishes living there based on our molecular clock estimates. We also identified ten species that have likely experienced historical introgression. Most introgression events were between different groups within the northern New Guinea lineage and the Southern New Guinea/Australian lineages. Finally, we identified nearly 20 undescribed species within Melanotaeniidae, demonstrating that much work remains in describing freshwater fish diversity in this region.


Assuntos
Evolução Molecular , Peixes/classificação , Filogenia , Animais , Austrália , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Peixes/genética , Íntrons , Funções Verossimilhança , Modelos Genéticos , Nova Guiné , Análise de Sequência de DNA
9.
Science ; 330(6010): 1503-9, 2010 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-20978281

RESUMO

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Vertebrados , Anfíbios , Animais , Aves , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Extinção Biológica , Espécies Introduzidas , Mamíferos , Dinâmica Populacional
10.
Biol Lett ; 5(2): 258-61, 2009 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-19126528

RESUMO

Studying hybridization is crucial to understanding speciation and almost all our knowledge comes from terrestrial and freshwater environments. Marine hybrids are considered rare, particularly on species-rich coral reefs. Here, we report a significant marine hybrid zone at Christmas and Cocos Islands (eastern Indian Ocean) with 11 hybrid coral reef fishes (across six families); the most recorded hybrids of any marine location. In most cases, at least one of the parent species is rare (less than three individuals per 3000 m(2)), suggesting that hybridization has occurred because individuals of the rare species have mated with another species owing to a scarcity of conspecific partners. These islands also represent a marine suture zone where many of the hybrids have arisen through interbreeding between Indian and Pacific Ocean species. For these species, it appears that past climate changes allowed species to diverge in allopatry, while recent conditions have facilitated contact and subsequent hybridization at this Indo-Pacific biogeographic border. The discovery of the Christmas-Cocos hybrid zone refutes the notion that hybridization is lacking on coral reefs and provides a natural laboratory for testing the generality of terrestrially derived hybridization theory in the marine environment.


Assuntos
Ecossistema , Hibridização Genética , Perciformes/genética , Animais , Feminino , Oceano Índico , Masculino , Micronésia , Oceano Pacífico
11.
Conserv Biol ; 22(4): 965-75, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18786099

RESUMO

Endemism is thought to be relatively rare in marine systems due to the lack of allopatric barriers and the potential for long-distance colonization via pelagic larval dispersal. Although many species of coral reef fishes exhibit regionally restricted color variants that are suggestive of regional endemism, such variation is typically ascribed to intraspecific variation. We examined the genetic structure in 5 putatively monospecific fishes from the Indo-West Pacific (Amphiprion melanopus, Chrysiptera talboti, and Pomacentrus moluccensis [Pomacentridae] and Cirrhilabrus punctatus, and Labroides dimidiatus [Labridae]) that express regional color variation unique to this area. Mitochondrial-control-region sequence analysis showed shallow to deep genetic divergence in all 5 species (sequence divergence 2-17%), with clades concordant with regional color variation. These results were partially supported by nuclear RAG2 data. An analysis of molecular variation (AMOVA) mirrored the phylogenetic results; Phi(ST) values ranged from 0.91 to 0.7, indicating high levels of geographic partitioning of genetic variation. Concordance of genetics and phenotype demonstrate the genetic uniqueness of southwestern Pacific color variants, indicating that these populations are at a minimum distinct evolutionarily significant units and perhaps distinct regionally endemic species. Our results indicate that the alpha biodiversity of the southwestern Pacific is likely underestimated even in well-studied groups, such as reef fishes, and that regional endemism may be more common in tropical marine systems than previously thought.


Assuntos
Ecossistema , Peixes/genética , Peixes/fisiologia , Animais , Antozoários , Conservação dos Recursos Naturais , DNA/genética , Variação Genética , Filogenia , Pigmentos Biológicos , Dinâmica Populacional
12.
Proc Biol Sci ; 274(1609): 591-8, 2007 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-17476781

RESUMO

The interaction structure of mutualistic relationships, in terms of relative specialization of the partners, is important to understanding their ecology and evolution. Analyses of the mutualistic interaction between anemonefish and their host sea anemones show that the relationship is highly nested in structure, generalist species interacting with one another and specialist species interacting mainly with generalists. This supports the hypothesis that the configuration of mutualistic interactions will tend towards nestedness. In this case, the structure of the interaction is at a much larger scale than previously hypothesized, across more than 180 degrees of longitude and some 60 degrees of latitude, probably owing to the pelagic dispersal capabilities of these species in a marine environment. Additionally, we found weak support for the hypothesis that geographically widespread species should be more generalized in their interactions than species with small ranges. This study extends understanding of the structure of mutualistic relationships into previously unexplored taxonomic and physical realms, and suggests how nestedness analysis can be applied to the conservation of obligate species interactions.


Assuntos
Ecossistema , Perciformes/fisiologia , Anêmonas-do-Mar/fisiologia , Animais , Especificidade da Espécie , Simbiose
13.
Science ; 295(5558): 1280-4, 2002 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11847338

RESUMO

Coral reefs are the most biologically diverse of shallow water marine ecosystems but are being degraded worldwide by human activities and climate warming. Analyses of the geographic ranges of 3235 species of reef fish, corals, snails, and lobsters revealed that between 7.2% and 53.6% of each taxon have highly restricted ranges, rendering them vulnerable to extinction. Restricted-range species are clustered into centers of endemism, like those described for terrestrial taxa. The 10 richest centers of endemism cover 15.8% of the world's coral reefs (0.012% of the oceans) but include between 44.8 and 54.2% of the restricted-range species. Many occur in regions where reefs are being severely affected by people, potentially leading to numerous extinctions. Threatened centers of endemism are major biodiversity hotspots, and conservation efforts targeted toward them could help avert the loss of tropical reef biodiversity.


Assuntos
Cnidários , Conservação dos Recursos Naturais , Ecossistema , Peixes , Nephropidae , Caramujos , Animais , Cnidários/classificação , Cnidários/fisiologia , Peixes/classificação , Peixes/fisiologia , Humanos , Nephropidae/classificação , Nephropidae/fisiologia , Água do Mar , Caramujos/classificação , Caramujos/fisiologia , Clima Tropical
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