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1.
Science ; 376(6598): 1215-1219, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35679394

RESUMO

Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community composition at such geographic scales remains unknown. Using standardized experiments that spanned 115° of latitude, at 36 nearshore sites along both coasts of the Americas, we found that marine predators have both higher consumption rates and consistently stronger impacts on biomass and species composition of marine invertebrate communities in warmer tropical waters, likely owing to fish predators. Our results provide robust support for a temperature-dependent gradient in interaction strength and have potential implications for how marine ecosystems will respond to ocean warming.


Assuntos
Organismos Aquáticos , Biomassa , Peixes , Temperatura Alta , Invertebrados , Comportamento Predatório , Animais , Aquecimento Global , Oceanos e Mares
2.
Mar Pollut Bull ; 133: 568-577, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30041351

RESUMO

Hydroid assemblage's responses to organic contamination were evaluated using sedimentary sterols as explanatory variables. At seven coral reef sites in the Havana west coast, hydroids were collected along three 10 m × 1 m, 10 m deep transects. Five sterols were analysed, i.e., coprostanol, an indicator of faecal contamination, and cholestanol, cholesterol, stigmasterol and brassicasterol, indicators of biogenic organic matter inputs. The sampling sites were classified by level of contamination. A total of 65 species comprised the hydroid assemblages. Hydroids community abundance and richness decreased in the contaminated sites. Coprostanol had the highest relative importance for these variables and also for Plumularia floridana and Clytia gracilis abundances. Obelia dichotoma and Halecium bermudense were relatively abundant in the contaminated sites. The results indicate that faecal contamination negatively affected the hydroid assemblages, highlighting the importance of integrated biological and chemical indicators to evaluate the environmental conditions of the Havana coral reef.


Assuntos
Recifes de Corais , Biomarcadores Ambientais , Hidrozoários/fisiologia , Esteróis/análise , Poluição da Água/efeitos adversos , Animais , Biodiversidade , Colestanol/análise , Cuba , Ecossistema , Fezes , Sedimentos Geológicos/análise
3.
Zootaxa ; 4194(1): zootaxa.4194.1.1, 2016 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-27988700

RESUMO

We have compiled available records in the literature for medusozoan cnidarians and ctenophores of South America. New records of species are also included. Each entry (i.e., identified species or still as yet not determined species referred to as "sp." in the literature) includes a synonymy list for South America, taxonomical remarks, notes on habit, and information on geographical occurrence. We have listed 800 unique determined species, in 958 morphotype entries: 5 cubozoans, 905 hydrozoans, 25 scyphozoans, 3 staurozoans, and 20 ctenophores. Concerning nomenclatural and taxonomical decisions, two authors of this census (Miranda, T.P. & Marques, A.C.) propose Podocoryna quitus as a nomen novum for the junior homonym Hydractinia reticulata (Fraser, 1938a); Euphysa monotentaculata Zamponi, 1983b as a new junior synonym of Euphysa aurata Forbes, 1848; and Plumularia spiralis Milstein, 1976 as a new junior synonym of Plumularia setacea (Linnaeus, 1758). Finally, we also reassign Plumularia oligopyxis Kirchenpauer, 1876 as Kirchenpaueria oligopyxis (Kirchenpauer, 1876) and Sertularella margaritacea Allman, 1885 as Symplectoscyphus margaritaceus (Allman, 1885).


Assuntos
Ctenóforos/classificação , Distribuição Animal , Animais , Ecossistema , Feminino , Masculino , América do Sul
4.
Zootaxa ; (3796): 494-506, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24870689

RESUMO

Podocoryna loyola, a new hydractiniid species, has been found on artificial substrates in Baía de Paranaguá, southern coast of Brazil, since April 2007. Its main morphological characteristics are: (1) polymorphic colonies with reticular stolons or encrusting hydrorhiza not covered by periderm and smooth chitinous spines; (2) newly-released medusae with eight tentacles and small interradial gonads; (3) mature medusae with eight tentacles and unbranched oral lips; gastric peduncle absent. Molecular data show that P. loyola is distinct from all other examined species of Podocoryna, and from P. hayamaensis Hirohito (1988), its sister species from Japan. As the polyps having been noted only quite recently, and in having been found only on man-made objects in port areas and estuaries, the species is most likely exotic to the region.


Assuntos
Hidrozoários/anatomia & histologia , Espécies Introduzidas , Animais , Brasil , Hidrozoários/genética
5.
Zootaxa ; 3768: 291-326, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24871179

RESUMO

This study is the first faunistic inventory of hydromedusae from the inner continental shelf of Paraná State. We describe the composition of hydromedusae species, collected with bottom-trawl and Hensen nets, in campaigns carried out from 1997 to 2006. We analyzed 17,797 specimens from 578 samples, and provide descriptions, photographs, and information about the biology of the 22 species found. All species had previous records from the Brazilian coast; however, this is the first record of Bougainvillia frondosa, Ectopleura dumortieri, Cirrholovenia tetranema, Eucheilota maculata, Gossea brachymera, Solmaris corona, and Amphogona apsteini for the coast of Paraná. Most species are typical of tropical and subtropical coastal waters from the South Brazilian Bight. However, Turritopsis nutricula, Niobia dendrotentaculata, Solmaris corona, and Aglaura hemistoma are abundant in oceanic waters, and Olindias sambaquiensis and Solmaris corona are associated with colder waters (<20°C). The current number of species known for the state is 26. Additional collection effort is needed in regions not sampled in this work, such as bays and offshore waters.


Assuntos
Cnidários/anatomia & histologia , Cnidários/classificação , Animais , Oceano Atlântico , Brasil , Cnidários/fisiologia , Demografia , Especificidade da Espécie
6.
Biota neotrop. (Online, Ed. port.) ; 11(3): 331-353, jul.-set. 2011. ilus, mapas, tab
Artigo em Português | LILACS | ID: lil-610581

RESUMO

A fauna de hidroides bentônicos do infralitoral raso, de seis locais do município de Bombinhas (Santa Catarina, Brasil), foi pesquisada e analisada com base na morfologia. O cnidoma foi examinado quando necessário para a identificação específica. Foram encontradas 25 espécies, das quais cinco (20 por cento) são registradas pela primeira vez para o estado de Santa Catarina e três (12 por cento) são registradas pela primeira vez para a região sul do Brasil. Houve um acréscimo de 12 por cento e 5,5 por cento nos registros de espécies de hidroides para Santa Catarina e litoral sul brasileiro, respectivamente.


The benthic hydroid fauna from shallow subtidal zone of six localities in the municipality of Bombinhas (state of Santa Catarina, Brazil) was surveyed and its morphology analysed. Cnidome was also examined when it was necessary for species identification. Twenty five morphospecies were found, from which five (20 percent) were recorded for the first time in Santa Catarina State and three (12 percent) were recorded for the first time in the south region of Brazil. There was a 12 percent and 5.5 percent increase in the records of benthic hydroid species for Santa Catarina and southern Brazilian coast, respectively.

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