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1.
Sci Rep ; 14(1): 7893, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570549

RESUMO

The Anthropocene rise in global temperatures is facilitating the expansion of tropical species into historically non-native subtropical locales, including coral reef fish. This redistribution of species, known as tropicalization, has serious consequences for economic development, livelihoods, food security, human health, and culture. Measuring the tropicalization of subtropical reef fish assemblages is difficult due to expansive species ranges, temporal distribution shifts with the movement of isotherms, and many dynamic density-dependent factors affecting occurrence and density. Therefore, in locales where tropical and subtropical species co-occur, detecting tropicalization changes relies on regional analyses of the relative densities and occurrence of species. This study provides a baseline for monitoring reef fish tropicalization by utilizing extensive monitoring data from a pivotal location in southeast Florida along a known transition between tropical and subtropical ecotones to define regional reef fish assemblages and use benthic habitat maps to spatially represent their zoogeography. Assemblages varied significantly by ecoregion, habitat depth, habitat type, and topographic relief. Generally, the southern assemblages had higher occurrences and densities of tropical species, whereas the northern assemblages had a higher occurrence and density of subtropical species. A total of 108 species were exclusive to regions south of the Bahamas Fracture Zone (BFZ) (South Palm Beach, Deerfield, Broward-Miami) and 35 were exclusive to the north (North Palm Beach, Martin), supporting the BFZ as a pivotal location that affects the coastal biogeographic extent of tropical marine species in eastern North America. Future tropicalization of reef fish assemblages are expected to be evident in temporal deviance of percent occurrence and/or relative species densities between baseline assemblages, where the poleward expansion of tropical species is expected to show the homogenization of assemblage regions as adjacent regions become more similar or the regional boundaries expand poleward. Ecoregions, habitat depth, habitat type, and relief should be incorporated into the stratification and analyses of reef fish surveys to statistically determine assemblage differences across the seascape, including those from tropicalization.


Assuntos
Recifes de Corais , Fraturas Ósseas , Animais , Humanos , Ecossistema , Peixes , Florida , Bahamas
2.
PeerJ ; 11: e15854, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37842057

RESUMO

Vermetid worm-snails are sessile and irregularly coiled marine mollusks common in warmer nearshore and coral reef environments that are subject to high predation pressures by fish. Often cryptic, some have evolved sturdy shells or long columellar muscles allowing quick withdrawal into better protected parts of the shell tube, and most have variously developed opercula that protect and seal the shell aperture trapdoor-like. Members of Thylacodes (previously: Serpulorbis) lack such opercular protection. Its species often show polychromatic head-foot coloration, and some have aposematic coloration likely directed at fish predators. A new polychromatic species, Thylacodes bermudensis n. sp., is described from Bermuda and compared morphologically and by DNA barcode markers to the likewise polychromatic western Atlantic species T. decussatus (Gmelin, 1791). Operculum loss, previously assumed to be an autapomorphy of Thylacodes, is shown to have occurred convergently in a second clade of the family, for which a new genus Cayo n. gen. and four new western Atlantic species are introduced: C. margarita n. sp. (type species; with type locality in the Florida Keys), C. galbinus n. sp., C. refulgens n. sp., and C. brunneimaculatus n. sp. (the last three with type locality in the Belizean reef) (all new taxa authored by Bieler, Collins, Golding & Rawlings). Cayo n. gen. differs from Thylacodes in morphology (e.g., a protoconch that is wider than tall), behavior (including deep shell entrenchment into the substratum), reproductive biology (fewer egg capsules and eggs per female; an obliquely attached egg capsule stalk), and in some species, a luminous, "neon-like", head-foot coloration. Comparative investigation of the eusperm and parasperm ultrastructure also revealed differences, with a laterally flattened eusperm acrosome observed in two species of Cayo n. gen. and a spiral keel on the eusperm nucleus in one, the latter feature currently unique within the family. A molecular phylogenetic analysis based on mitochondrial and nuclear rRNA gene sequences (12SrRNA, trnV, 16SrRNA, 28SrRNA) strongly supports the independent evolution of the two non-operculate lineages of vermetids. Thylacodes forms a sister grouping to a clade comprising Petaloconchus, Eualetes, and Cupolaconcha, whereas Cayo n. gen is strongly allied with the small-operculate species Vermetus triquetrus and V. bieleri. COI barcode markers provide support for the species-level status of the new taxa. Aspects of predator avoidance/deterrence are discussed for these non-operculate vermetids, which appear to involve warning coloration, aggressive behavior when approached by fish, and deployment of mucous feeding nets that have been shown, for one vermetid in a prior study, to contain bioactive metabolites avoided by fish. As such, non-operculate vermetids show characteristics similar to nudibranch slugs for which the evolution of warning coloration and chemical defenses has been explored previously.


Assuntos
Recifes de Corais , Caramujos , Animais , Masculino , Feminino , Filogenia , Caramujos/anatomia & histologia , Ovos , Alimentos Marinhos
3.
J Fish Biol ; 103(5): 1237-1241, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37526309

RESUMO

We describe the first recorded association between fishes and nudibranchs in epipelagic waters. In situ observations and photographs of a juvenile spotted driftfish Ariomma regulus (Stromateiformes; Ariommatidae) swimming alongside the planktonic nudibranch Phylliroe lichtensteinii (Gastropoda; Phylliroidae) were made during blackwater scuba dives off Palm Beach, Florida, United States of America. In this paper, we describe this behavior, highlighting a previously undocumented zooplanktonic host used by fishes. This finding also demonstrates the importance of community science in advancing our understanding of the early life history of marine species.


Assuntos
Peixes , Gastrópodes , Animais , Plâncton , Natação , Florida , Moluscos
4.
PeerJ ; 11: e14751, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36815990

RESUMO

The taxonomic status of the sergestid shrimp, Acetes americanus, has been questioned for several decades. No specific study has been performed thus far to resolve the incongruences. This species has a wide geographical range in the western Atlantic and is represented by two formally accepted subspecies: Acetes americanus carolinae, distributed in North America, and Acetes americanus americanus, present in South America. However, there are regions where the coexistence of both subspecies has been reported, such as Central America. This study aimed to genetically compare specimens of A. a. americanus collected in South America with A. a. carolinae sampled in North America to check for possible differences and the existence of more than one subspecies of A. americanus on the Brazilian coast. Based on the sequences of two informative markers, the cytochrome oxidase I region (COI) and 16S rRNA, phylogenetic reconstruction demonstrated well-defined clades with high support values, reinforcing the idea that A. a. americanus is genetically different from A. a. carolinae. Our hypothesis was corroborated as the specimens collected in Brazil were divided into two distinct lineages: the first composed of A. a. americanus sensu stricto (Brazil 1) and the second by Acetes americanus (Brazil 2). The three groups evidenced in the haplotype network were the same as those observed in the phylogenetic tree. The morphometric character (height/length of the thelycum) was effective in distinguishing A. a. Brazil 1 from A. a. carolinae. However, more detailed and conclusive studies comprising other characteristics to propose and describe a possible new entity are necessary. To the best of our knowledge, for the first time, the results of this study provide some insights into the taxonomic status of the sergestid shrimp A. americanus in the western Atlantic.


Assuntos
Decápodes , Animais , Filogenia , RNA Ribossômico 16S/genética , Decápodes/genética , Crustáceos/genética , Brasil , Variação Genética
5.
J Phycol ; 58(6): 731-745, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36054695

RESUMO

Continuing molecular studies of the red algal genus Dasya collected off the coast of Bermuda have revealed two new species in the developing D. cryptica species complex-one from each the euphotic and mesophotic zones, D. orae sp. nov. and D. bathypelagica sp. nov., respectively. Furthermore, what was known as D. baillouviana in Bermuda is shown to represent D. hibernae sp. nov., a sibling of D. pedicellata from New England and New York, USA. Despite morphological similarities to the recently described shallow subtidal species from the islands, D. cryptica, molecular sequencing and morphological comparisons demonstrated that a new set of inshore specimens represented D. orae. The larger, new deep-water species, D. bathypelagica, was genetically compared with recent Bermuda collections of D. baillouviana and others worldwide morphologically falling under this epithet and represented a new species also grouping in the D. cryptica complex. The specimens of D. hibernae from Bermuda were shown to be genetically distinct from specimens of D. pedicellata from southern New England and New York. Molecular analyses necessitated the resurrection of D. pedicellata and uncovered undescribed species in the D. baillouviana complex in the western Atlantic. Based upon genetic evidence provided here, the generitype of Rhodoptilum nested among species in the D. baillouviana complex including the generitype. This finding required the synonymy of the genus Rhodoptilum with Dasya and allowed for the reinstatement of D. plumosa. Furthermore, Dasya collinsiana resolved in the lineage including a closely related species to the generitype of Dasysiphonia, necessitating the transfer of this Bermudian species and others worldwide from the genus Dasya to Dasysiphonia.


Assuntos
Rodófitas , Filogenia , Bermudas , Rodófitas/genética , New York
6.
J Fish Biol ; 101(3): 522-539, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35633502

RESUMO

Anchoviella cayennensis (Puyo, 1945) is a relatively small-sized, coastal and estuarine western Atlantic species of anchovy distributed from Suriname to southeastern Brazil. The species is morphologically similar to Anchoviella perfasciata (Poey, 1860) from the Central and western North Atlantic, and it has been suggested in the literature that both are actually synonyms. The recently described Anchoviella sanfranciscana (Barbosa et al., 2017) was reported as endemic to the estuary of the São Francisco River, northeastern Brazil. Most characters proposed as diagnostic for A. sanfranciscana in the description are, however, similar to the ones reported for A. cayennensis and A. perfasciata. To determine the complex taxonomic scenario involving the three species, 24 morphometric and 13 meristic characters of 171 specimens tentatively identified as A. perfasciata (including the holotype) and A. cayennensis from the Central and South Atlantic in addition to the holotype and 19 paratypes of A. sanfranciscana (total: 191 specimens) were analysed. The PCAs of morphometric characters indicate the existence of two groups, which are recognized as A. perfasciata and A. cayennensis, with A. sanfranciscana proposed as a junior synonym of the later. Further evidence from gill arch dentition also indicates that A. perfasciata and A. cayennensis are distinct valid species. A redescription of A. cayennensis is presented, with a neotype proposed for the species. Confirmation of the identity of specimens attributed to A. cayennensis indicates that its southern limit of distribution is in the Rio de Janeiro State, southeastern Brazil. An updated taxonomic key for the estuarine and coastal Atlantic species of Anchoviella is also presented.


Assuntos
Peixes , Brânquias , Animais , Brasil , Rios , Alimentos Marinhos
7.
PeerJ ; 9: e12108, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540376

RESUMO

'Miniaturization' is a widespread phenomenon among the Metazoa. In the molluscan class Bivalvia, records of miniaturization are numerous. Among the Archiheterodonta, Warrana besnardi (Klappenbach, 1963) has attracted attention for its tiny size, which does not exceed 1.5 mm in shell length, and because it belongs to a group with limited anatomical information and often-debated status, the "Condylocardiidae" (which recent molecular studies place deeply nested within the family Carditidae). All species of Warrana Laseron, 1953 are small-bodied, and so miniaturization presumably occurred from a large-bodied ancestor within the Carditidae sensu lato. South American W. besnardi is here studied in detail. Its small size and the enlargement of the anterodorsal region during growth, reflects (and likely led) to infaunal habit, living as a burrowing bivalve that passively feeds on deposit particles entering the pallial cavity anteriorly. Mantle glands, previously reported as a common feature of other archiheterodonts, are missing in W. besnardi, but spongiform tissue in the antero-ventral portion of the mantle lobes presumably represents a blood sinus that might compensate for the great reduction of the ctenidia. Lecithotrophy is reported, with yolky oocytes bearing a thick non-cellular capsule layer; brooding was not observed, and it is here hypothesized that the extreme miniaturization, with the great reduction of ctenidia, is responsible for a shift in the reproductive mode of condylocardiids, contrasting with the commonly reported ovoviviparity of the carditids.

8.
J Fish Biol ; 99(4): 1292-1298, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34180056

RESUMO

In this study, a new species of Pseudogilbia Møller, Schwarzhans & Nielsen 2004 is described based on two male specimens (40-44 mm LS ) from shallow reefs of Bahia, Brazil. Pseudogilbia australis sp. nov. is distinguished from its only congener, Pseudogilbia sanblasensis Møller, Schwarzhans & Nielsen 2004 from Caribbean Panama, by having: two lower preopercular pores (vs. one); dorsal-fin rays 65-67 (vs. 69); anal-fin rays 51-53 (vs. 56); pectoral-fin rays 18 (vs. 20); caudal vertebrae 27-28 (vs. 30); pectoral-fin length 15.0%-15.9% LS (vs. 14.3); pelvic-fin length 13.5% LS (vs. 16.4) and a different morphology of the male copulatory organ. Pseudogilbia australis sp. nov. is the only dinematichthyid so far recorded in the South Atlantic. An updated diagnosis for the genus is also provided.


Assuntos
Perciformes , Animais , Brasil , Região do Caribe , Peixes , Masculino , Panamá
9.
PeerJ ; 9: e10775, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859870

RESUMO

BACKGROUND: Among all present demosponges, lithistids represent a polyphyletic group with exceptionally well-preserved fossils dating back to the Cambrian. Knowledge of their recent diversity, particularly in the Tropical Western Atlantic Ocean (TWA) where they are common in deep waters, is scarce making any comparison between present and past major 'lithistid' faunas difficult. In addition, the lack of sufficient molecular and morphological data hamper any predictions on phylogenetic relationships or phylodiversity from this region. The Harbor Branch Oceanographic Institute (HBOI, Fort Pierce, Florida) holds the largest collection of TWA lithistid sponges worldwide, however, the majority remain to be taxonomically identified and revised. PRINCIPAL FINDINGS: In this study we provide sequences of 249 lithistid demosponges using two independent molecular markers (28S rDNA (C1-D2) and cox1 mtDNA). In addition, a morphological documentation of 70 lithistid specimens is provided in the database of the Sponge Barcoding Project (SBP). This integrated dataset represents the largest and most comprehensive of the TWA lithistids to date. The phylogenetic diversity of 'lithistid' demosponges in the Bahamas and Jamaica are high in comparison to other TWA regions; Theonellidae and Corallistidae dominate the fauna, while Neopeltidae and Macandrewiidae are rare. A proposed tetractinellid suborder, one undescribed genus and several undescribed species are recognized and the Pacific 'lithistid' genera, Herengeria and Awhiowhio, are reported from the TWA for the first time. The higher-taxa relationships of desma-bearing tetractinellids are discussed and topics for revision suggested. CONCLUSION: This first integrative approach of TWA 'lithistid' demosponges contributes to a better understanding of their phylogenetic affinities, diversity and bathymetric distribution patterns within the TWA. As in the Pacific, the TWA 'lithistid' demosponges dominate deep-water habitats. Deeper taxonomic investigations will undoubtedly contribute to a better comparison between present major 'lithistid' faunas and their fossil record in the Mesozoic.

10.
J Fish Biol ; 99(3): 856-874, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33913166

RESUMO

Tracking 47 post-spawned adult Atlantic salmon Salmo salar L. in a hydropower-regulated river through autumn, winter and spring revealed that winter survival was 56% and 75% in two study years, respectively, with higher mortality of males than females (50% vs. 33% and 100% vs. 13%, respectively). Some kelts (n = 7) displayed nondirected movements that were interpreted as a reconditioning period for an average of 9-17 days prior to directed downstream movements indicating the initiation of migration. Survival after the initiation of migration in spring was 83% and 94% to the hydropower dam in the first and second study years, and decreased to 60 and 63%, respectively, after dam passage. There were no further losses in the downriver reach in the second year, with the first year having a cumulative survival estimate of 53% to the river mouth. Kelts approached the dam when the spillway gates were available as a passage option most of the time (64%-75%), but some kelts arrived at the dam or had not yet passed when spillways were closed (n = 6) and the only remaining passage option was restricted to the turbines. However, all but one kelt that must have passed via turbine were successful in reaching the river mouth. Migratory delay presumably due to searching behaviour caused by low water flow was estimated at approximately 6 days as migration rates were significantly slower in the reservoir (median ± s.e. 8.5 ± 2.5 km day-1 ) than up- (29.7 ± 5.0 km day-1 ) or downriver (22.1 ± 3.1 km day-1 ). The proportion of time (median 30%) that kelts spent swimming upstream (searching behaviour) in the reservoir was a significant variable for migration success.


Assuntos
Salmo salar , Migração Animal , Animais , Feminino , Masculino , Rios , Estações do Ano , Natação
11.
Parasite ; 28: 34, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33835020

RESUMO

The coquina, Donax variabilis, is a known intermediate host of monorchiid and gymnophallid digeneans. Limited morphological criteria for the host and the digeneans' larval stages have caused confusion in records. Herein, identities of coquinas from the United States (US) Atlantic coast were verified molecularly. We demonstrate that the current GenBank sequences for D. variabilis are erroneous, with the US sequence referring to D. fossor. Two cercariae and three metacercariae previously described in the Gulf of Mexico and one new cercaria were identified morphologically and molecularly, with only metacercariae occurring in both hosts. On the Southeast Atlantic coast, D. variabilis' role is limited to being a facultative second intermediate host, and D. fossor, an older species, acts as both first and second intermediate hosts. Sequencing demonstrated 100% similarities between larval stages for each of the three digeneans. Sporocysts, single tail cercariae, and metacercariae in the incurrent siphon had sequences identical to those of monorchiid Lasiotocus trachinoti, for which we provide the complete life cycle. Adults are not known for the other two digeneans, and sequences from their larval stages were not identical to any in GenBank. Large sporocysts, cercariae (Cercaria choanura), and metacercariae in the coquinas' foot were identified as Lasiotocus choanura (Hopkins, 1958) n. comb. Small sporocysts, furcocercous cercariae, and metacercariae in the mantle were identified as gymnophallid Parvatrema cf. donacis. We clarify records wherein authors recognized the three digenean species but confused their life stages, and probably the hosts, as D. variabilis is sympatric with cryptic D. texasianus in the Gulf of Mexico.


TITLE: Les données moléculaires remodèlent notre compréhension des cycles de vie de trois Digènes (Monorchiidae et Gymnophallidae) parasites du bivalve Donax variabilis : ce n'est qu'un hôte facultatif ! ABSTRACT: La telline, Donax variabilis, est un hôte intermédiaire connu de digènes Monorchiidae et Gymnophallidae. Le nombre limité de critères morphologiques pour identifier les hôtes et les stades larvaires des parasites sont à la base de confusion dans la littérature. Dans cette étude nous avons identifié par séquençage les tellines collectées sur la côte Atlantique des États-Unis. Nous démontrons que les séquences pour D. variabilis dans GenBank sont incorrectes et que celle du spécimen américain est en fait celle de D. fossor. Deux cercaires et trois métacercaires décrites au préalable dans le Golfe du Mexique ainsi qu'une nouvelle cercaire ont été identifiées morphologiquement et par séquençage. Les métacercaires seules infectent les deux hôtes. Sur la côte sud-est Atlantique, D. variabilis a un rôle limité à seulement celui de second hôte intermédiaire facultatif, et D. fossor, une espèce plus ancienne, est premier et second hôte intermédiaire. Le séquençage a montré 100 % de similarité entre les stades larvaires de chacun des trois digènes. Des sporocystes avec des cercaires à queue simple et les métacercaires dans le siphon inhalant ont des séquences identiques à celles de Lasiotocus trachinoti, pour qui nous donnons le cycle complet. Les adultes des deux autres digènes ne sont pas connus et les séquences des stades larvaires ne sont identiques à aucune dans GenBank. Des sporocystes de grande taille, les cercaires (Cercaria choanura) et les métacercaires enkystées dans le pied des tellines sont identifiées comme étant Lasiotocus choanura (Hopkins, 1958) n. comb. Des petits sporocystes avec des furcocercaires et des métacercaires dans le manteau des tellines sont identifiées comme étant le gymnophallide Parvatrema cf. donacis. Nous clarifions les rapports de la littérature dans lesquels les auteurs ont reconnu les trois espèces de digènes mais ont confondu leurs stades larvaires et probablement les hôtes étant donné que D. variabilis vit en sympatrie avec l'espèce cryptique D. texasianus dans le Golfe du Mexique.


Assuntos
Bivalves , Trematódeos , Animais , Cercárias , Estágios do Ciclo de Vida , Metacercárias , Trematódeos/genética
12.
Zootaxa ; 4933(1): zootaxa.4933.1.2, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33756803

RESUMO

Free-living bryozoans, unlike most cheilostomes, live unattached from the substratum on or within soft sedimentary bottoms. Bryozoans of the family Cupuladriidae Lagaaij, 1952 are probably the best-studied free-living representatives. In Brazil, eight species of cupuladriids have been reported to date, including some regarded as species complexes. This paper documents cupuladriid taxa from northeastern and northern Brazil based on the examination of 1236 colonies. Three species previously reported from Brazil are described: Cupuladria monotrema (Busk, 1884), Discoporella gemmulifera Winston Vieira, 2013 and Discoporella salvadorensis Winston, Vieira Woollacott, 2014. A new species, Cupuladria minuta n. sp., is erected; it differs from its congeners in having small, flat discoid colonies, with the central area up to the fifth astogenetic generation composed of vicarious avicularia with an auriform opesia, and quadrangular to rectangular basal sectors with 1-6 small openings per sector. Our results suggest that four species previously recorded from Brazil are doubtful-Cupuladria canariensis (Busk, 1859), Cupuladria biporosa Canu Bassler, 1923, Discoporella umbellata (Defrance, 1923) and Discoporella depressa (Conrad, 1841). Some Brazilian specimens previously assigned to Discoporella umbellata var. conica are re-assigned to D. salvadorensis. The species studied here frequently co-occur on mainly sandy and muddy bottoms at 8-130 m depth, as it is typical of most living populations of cupuladriids. The sedimentation rate, and thus the bottom composition, likely influence the distribution of cupuladriids in Brazil, with Cupuladria species being more common in stabler and coarser sea bottoms than Discoporella species, which tend to be more broadly distributed.


Assuntos
Briozoários , Animais , Brasil
13.
J Fish Biol ; 98(2): 470-484, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33058185

RESUMO

As environmental change persists, understanding resource use patterns is of value to predict the consequences of shifting trophic structures. While many sharks are opportunistic predators, some exhibit prey selectivity, putting them at higher risk compared to species with greater trophic plasticity. In the Gulf of Mexico (GOM), Clupeids and Sciaenids comprise 69% of blacktip shark (Carcharhinus limbatus) diets, which is consequential considering potential responses of these prey groups to disturbance and over harvesting. We assessed if blacktips exhibit selectivity for Clupeids and Sciaenids in the western GOM based on stomach contents from sharks in coastal Texas. Clupeids comprised <2% of diets, while striped mullet (Mugil cephalus) and red drum (Sciaenops ocellatus) comprised >70% of identifiable prey. Ontogenetic shifts from smaller (Clupeids, small Sciaenids) to larger, higher trophic level (Ariidae, Elasmobranchii) prey fits our understanding of foraging among coastal sharks, and suggests our regional understanding of blacktip trophic ecology may be limited by the sizes of sampled sharks. Observed increases in blacktip densities coupled with declines in prey (Mugilids, Sciaenids) is concerning if blacktips have limited diet plasticity. Yet GOM blacktips may be more generalized than previously thought, which is promising for conservation and management.


Assuntos
Dieta , Estuários , Comportamento Predatório , Tubarões/fisiologia , Animais , Cadeia Alimentar , Conteúdo Gastrointestinal , Golfo do México
14.
Neotrop. ichthyol ; 19(2): e200109, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1279484

RESUMO

The fishes of the Haemulidae family are currently allocated to 19 genera with a worldwide distribution in the tropical and subtropical waters of the world's oceans. Brachygenys and Haemulon are important genera of reef fish in Brazil, as they occur in large shoals, which are both ecologically and commercially valuable. This study identified the Brazilian species of the genera Brachygenys and Haemulon using DNA barcodes. While we found only a single lineage in Brachygenys chrysargyrea, Haemulon melanurum, H. parra, and H. squamipinna, more than one molecular operational taxonomic unit (MOTU) was identified in H. atlanticus, H. aurolineatum, and H. plumieri, indicating the possible existence of discrete populations or cryptic species.(AU)


Os peixes da família Haemulidae estão atualmente distribuídos em 19 gêneros, com distribuição mundial em águas oceânicas tropicais e subtropicais. Brachygenys e Haemulon são importantes gêneros de peixes recifais do Brasil, visto que ocorrem em grandes cardumes, de valores ecológicos e comerciais. Este estudo identificou as espécies brasileiras dos gêneros Brachygenys e Haemulon usando o código de barras de DNA. Embora apenas uma única linhagem de Brachygenys chrysargyrea, Haemulon melanurum, H. parra e H. squamipinna tenha sido encontrada em nosso conjunto de dados, mais de uma unidade taxonômica operacional molecular (MOTU) foi identificada em H. atlanticus, H. aurolineatum e H. plumieri, indicando a possível existência de populações discretas ou espécies crípticas.(AU)


Assuntos
Animais , Perciformes , Distribuição de Produtos , Biologia Molecular , Análise de Sequência de DNA , Peixes
15.
Biota Neotrop. (Online, Ed. ingl.) ; 21(2): e20201125, 2021. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1278407

RESUMO

Abstract A case report of six brown booby (Sula leucogaster) envenomation following the ingestion of toadfish (Porichthys porosissimus) specimens in Rio de Janeiro, Southeastern Brazil is discussed herein. Several macro- and microscopic pathological alterations were observed in the examined brown booby specimens, and rapid envenomation (<24 h) is suggested due to the digestion stage of the fish found in their gastrointestinal tracts. This is the first report to mention the death of adult and juvenile brown boobies due to envenomation by the toadfish P. porosissimus. Further studies assessing the role of discarded fish as a driving force of negative effects on seabirds, such as envenomations, for example, along the southeastern coast of Brazil are recommended.


Resumo Um relato de caso sobre o envenenamento de seis indivíduos de atobás-marrons (Sula leucogaster) após a ingestão de espécimes de mangagá-liso (Porichthys porosissimus) no Rio de Janeiro, sudeste do Brasil, é discutido neste estudo. Diversas alterações patológicas macro e microscópicas foram observadas nos espécimes de atobá-marrom examinados, e um envenenamento rápido (<24 h) é sugerido devido ao estágio de digestão dos peixes encontrados em seus tubos digestórios. Este é o primeiro registro que menciona a morte de indivíduos juvenis e adultos de atobás marrons por envenenamento devido a ingestão do magangá-liso P. porosissimus. Novos estudos avaliando o papel dos peixes descartados como uma força motriz dos efeitos negativos sobre as aves marinhas como, por exemplo, envenenamentos, ao longo da costa sudeste do Brasil são recomendados.

16.
Glob Chang Biol ; 26(12): 6805-6812, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33021041

RESUMO

Interactions among species are likely to change geographically due to climate-driven species range shifts and in intensity due to physiological responses to increasing temperatures. Marine ectotherms experience temperatures closer to their upper thermal limits due to the paucity of temporary thermal refugia compared to those available to terrestrial organisms. Thermal limits of marine ectotherms also vary among species and trophic levels, making their trophic interactions more prone to changes as oceans warm. We assessed how temperature affects reef fish trophic interactions in the Western Atlantic and modeled projections of changes in fish occurrence, biomass, and feeding intensity across latitudes due to climate change. Under ocean warming, tropical reefs will experience diminished trophic interactions, particularly herbivory and invertivory, potentially reinforcing algal dominance in this region. Tropicalization events are more likely to occur in the northern hemisphere, where feeding by tropical herbivores is predicted to expand from the northern Caribbean to extratropical reefs. Conversely, feeding by omnivores is predicted to decrease in this area with minor increases in the Caribbean and southern Brazil. Feeding by invertivores declines across all latitudes in future predictions, jeopardizing a critical trophic link. Most changes are predicted to occur by 2050 and can significantly affect ecosystem functioning, causing dominance shifts and the rise of novel ecosystems.


Assuntos
Mudança Climática , Ecossistema , Animais , Brasil , Região do Caribe , Oceanos e Mares
17.
Zootaxa ; 4808(1): zootaxa.4808.1.3, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33055989

RESUMO

Brittle stars are considered one of the main benthic groups at the Brazilian coast, where they occur in high abundance and diversity. Ophiothrix Müller Troschel, 1840 is among the most common genera of ophiuroids, with hundreds of specimens deposited in Brazilian Zoological Collections. Here we reviewed the species of Ophiothrix of Brazil and elucidated the taxonomic status of the six species previously reported in Brazilian waters-Ophiothrix ailsae Tommasi, 1970, Ophiothrix angulata (Say, 1825), Ophiothrix brachyactis H. L. Clark, 1915, Ophiothrix rathbuni Ludwig, 1882, Ophiothrix suensoni Lütken, 1856 and Ophiothrix trindadensis Tommasi, 1970. Three of these were not found among the 1.134 specimens analyzed in this study-O. ailsae, O. angulata and O. brachyactis. Most specimens previously attributed to these three taxa are here assigned to Ophiothrix brasiliensis n. sp. due having disc covered by short spines with 2-6 thorns at the apex and triangular radial shields covered only by short bifid and trifid spines. Three other new species are also described. Ophiothrix spiniformis n. sp. has a disc covered by long spines with denticules along their complete length and an apex with spinelets and radial shields covered by short bifid and trifid spines. Ophiothrix tommasii n. sp. is characterized by the interradial regions of the disc and radial shields being covered by spines with 2-7 thorns at the tip, and by the presence of small spines on the first dorsal arm plate. Ophiothrix troscheli n. sp. has a disc covered by long conical spines and naked, triangular radial shields. An identification key for the Ophiothrix species of Brazil is provided.


Assuntos
Equinodermos , Animais , Brasil
18.
Zootaxa ; 4819(3): zootaxa.4819.3.4, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-33056093

RESUMO

The labrisomid genus Malacoctenus from Southwestern Atlantic is reviewed. Two new species of scaly blennies formerly reported by several authors as Malacoctenus triangulatus are described. One is found at the oceanic islands Fernando de Noronha Archipelago and Atol das Rocas, and the other is distributed along the Brazilian coastline. The two new species differ from other species of the genus and from each other by different combinations of the number of lateral-line scales, number and size of head cirri, and color pattern. Molecular data also support species' distinctiveness between M. triangulatus and the species described herein. Two additional recognized Brazilian species, M. delalandii and M. brunoi are described and illustrated and an identification key to all recognized Atlantic species is provided.


Assuntos
Peixes , Animais
19.
Zootaxa ; 4786(4): zootaxa.4786.4.4, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-33056461

RESUMO

At date, seven species of Stylopoma Levinsen, 1909 are reported from the Brazilian coast, five of which are known from Bahia State in the northeastern region. Here we describe four new species of Stylopoma, all from Bahia State: Stylopoma corallinum n. sp., Stylopoma faceluciae n. sp., Stylopoma multiavicularia n. sp. and Stylopoma sinuata n. sp. Unlike the Caribbean species of Stylopoma, that mainly have rounded primary orifice and slit-like sinus, the morphology of the primary orifice of Brazilian taxa, including the new species presented here, is quite variable. In the newly described taxa, the sinus is drop-shaped in S. corallinum n. sp. and S. faceluciae n. sp., U-shaped in S. multiavicularia n. sp. and V-shaped in S. sinuata n. sp. Like congeners from the Caribe, S. corallinum n. sp., S. faceluciae n. sp. and S. multiavicularia n. sp. have avicularia on the surface of the ooecia. Remarks on the morphological characters currently used in Stylopoma taxonomy are provided, including a comparative table of all living species worldwide.


Assuntos
Briozoários , Aranhas , Animais , Brasil
20.
Zootaxa ; 4845(3): zootaxa.4845.3.7, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-33056767

RESUMO

Several specimens of a small panopeid crab from coastal waters of the western Gulf of Mexico were long suspected to represent an undescribed species and are herein designated as representatives of a new genus. While the originally collected specimens from over four decades ago were not of gene-sequence quality, later collections from the same locality produced materials that yielded sequence data for inclusion in molecular phylogenetic studies. Building on results of those analyses, the present taxonomic description draws upon morphology to support the description of a unique species in which especially the male first gonopods differ from those of all other described panopeid genera. To date, the species remains known from only two western Gulf of Mexico sites, both of which are wave-washed intertidal rocky habitats where substrates are heavily burrowed by boring bivalves and sipunculans. While we cannot exclude the possibility that the species was introduced, recurrent collections show its populations to be at very least persistent, the species most likely being a long-overlooked among a confusing hard-substrate assemblage of small panopeid crabs.


Assuntos
Braquiúros , Animais , Ecossistema , Golfo do México , Masculino , Filogenia
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