Dactylopterus Research Articles

Isotopic niche of coastal fish and cephalopods off the Campos Basin, southeastern Brazil

The stable isotopes of carbon (δ13C) and nitrogen (δ15N) of three demersal guilds (benthic feeders, benthic/nekton feeders and nekton feeders) were assessed to understand their trophic relationships on the southeastern Brazilian coast. The organic matter (OM) pool that fuels the demersal food web is composed of a mixture of autochthonous (marine) and allochthonous (terrigenous) sources, highlighting the Paraíba do Sul River (PSR) influence in the shallow coastal waters, regardless of seasonality. Of the studied guilds, the nekton feeder guild (Doryteuthis plei, Lophius gastrophysus, Percophis brasiliensis and Saurida caribbaea) in the demersal food web had the highest δ15N’ values in the dry and rainy seasons. The benthic feeder guild (Atlantoraja platana, Dactylopterus volitans, Dules auriga, Etropus longimanus, Prionotus nudigula and Zapteryx brevirostris) presented the widest isotopic niche breadth (highest total niche area and trophic diversity) due to the assimilation of a variety of benthic crustaceans, with different isotope signatures. The assimilation of benthic and pelagic crustaceans by the benthic feeder and benthic/nekton feeder (Atlantoraja cyclophora, Octopus vulgaris and Priacanthus arenatus) guilds resulted in isotopic overlap (28.1–50.6%). Seasonal trends from benthic and inshore to pelagic and offshore associated food webs were observed for the benthic feeder and benthic/nekton feeder guilds. Our results highlight the importance of terrestrial OM sources from PSR to shallow coastal demersal food webs off inner and medium continental shelf in southeastern Brazil. In addition, the trophic relationships of megafauna from benthic to nekton feeders were discussed.

Foraging behaviour and diet of Brown boobies Sula leucogaster from Tinhosas Islands, Gulf of Guinea

Seabirds are a highly threatened group, yet the foraging ecology of several species remains poorly understood. Brown boobies breed in all oceans in the tropical region and are common across their range. In Tinhosa Grande (São Tomé and Príncipe), this species breeds in one of the largest colonies of seabirds in the east tropical Atlantic. We studied the foraging ecology of Brown boobies from this colony during the chick-rearing period. Thirty-three birds were tracked with GPS loggers and their diet was analysed from 11 regurgitations, using traditional and DNA barcoding techniques for prey identification. A total of 127 completed foraging trips were identified, 89% of which lasted less than 24 h. Females performed significantly longer trips and both sexes foraged preferentially over deep oceanic waters. The diet of Brown boobies included juvenile fish and squid (Sthenoteuthis pteropus), comprising mostly fish species whose juvenile phases live in the pelagic environment, and only migrate to coastal waters when adults. The most frequent of those prey found was Flying gurnard (Dactylopterus volitans). The relevance of such prey shows that Brown booby conservation depends not only on the management of their foraging areas and breeding sites but also on the correct management of the coastal adjacent areas that support the adult individuals of some of their prey. Our results suggest that the areas closest to the colony do not have available resources for these birds to feed on and that Brown boobies may be associate with subsurface marine predators or with sargassum patches to forage.

Diet of elasmobranchs captured in the fishing of pink shrimp off souther of Brazil / Dieta de elasmobrânquios capturados na pesca de camarão-rosa no sudeste e sul do Brasil

Some fish species compose the so-called bycatch caught by pink shrimp trawling, including elasmobranchs (sharks and rays). The objective of the study was to analyze the stomach contents of the captured and compare the items identified in the literature. The material was requested to the commercial vessels that landed in Guarujá, São Paulo, being the study area between Rio de Janeiro and Santa Catarina, from 5 to 75 meters deep. In the laboratory, total length-TL and sexing (shark and ray), fork length-FL (shark), disk width- DW (ray) in centimeters, and total weight- TW in kilograms (shark and ray). For the stomach contents, the Degree of Repletion adjusted (empty and full), the Degree of Digestion (undigested and unidentified), frequency of occurrence (%FO) and the numerical frequency (%FN). Sixty-two specimens were analyzed: 20 rays (seven Atlantoraja castelnaui , five A. cyclophora , five Dasyatis hypostigma , one Myliobatis freminvillei , one Gymnura altavela and one Sympterygia bonapartii ); and 42 sharks (29 Squatina guggenheim and 13 S. occulta ), between June 12 to September 19, 2015 and June 15 to December 29, 2016. Most of the food items had been mentioned in the literature, however others only in this study as : Sycionia sp. and Dactylopterus volitans ( D. hypostigma ); Polydactylus sp., Pogonias cromis and Dactylopterus volitans ( S. guggenheim ); and Porichthys porosissimus ( S. occulta ).

Signals of changes in the ichthyofauna composition of Galician waters (NW Iberian Peninsula)

Evidences of changes in the fish fauna of Galician waters is documented based on the occurrence of 24 specimens belonging to eight warm affinity fishes. Information about the morphology and new findings of Desmodema polystictum (Trachipteridae), Halobatrachus didactylus (Batrachoididae), Dactylopterus volitans (Dactylopteridae) Anthias anthias (Serranidae), Callanthias ruber (Callanthiidae), Seriola rivoliana (Carangidae), Uranoscopus scaber (Uranoscopidae) and Sphyraena sphyraena (Sphyraenidae), is reported from Galician waters, where they are unusual or rare. Morphometric and meristic parameters confirmed the identification to species level of each specimen, which was also supported by DNA barcoding. In addition, sex identification by histology and oocyte measurements of several specimens were carried out. The record of D. polystictum supposes the first occurrence for Atlantic European waters and a new northernmost record of the distribution in the Eastern Atlantic. A Neighbour-Joining comparison of COI mitochondrial DNA sequences of D. volitans suggests the possible occurrence of an undescribed cryptic species or the existence of a species that could be resurrected from one of its many catalogued synonyms. According to the obtained rate, S. rivoliana is the species more commonly recorded. The gonad histological analysis proposes A. anthias and C. ruber as protogynous hermaphrodite species.

Characterization of the complete mitochondrial genome of Dactylopterus volitans (Syngnathiformes, Dactylopteridae)

The complete mitochondrial genome was determined for the flying gurnard Dactylopterus volitans belonging to the family Dactylopteridae. The total length of the D. volitans mitochondrial genome is 16,632 bp, which consists of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and a control region. It has the typical vertebrate mitochondrial gene arrangement. Phylogenetic analysis using mitochondrial genomes of 20 species showed that D. volitans formed a well-supported monophyletic group with other Dactylopteridae species.

Digging with ‘hands’: observations of food capture in the flying gurnard Dactylopterus volitans (Linnaeus, 1758)

ABSTRACT Videofilms of a foraging flying gurnard (Dactylopterus volitans) were collected at Itaipu, Niterói, RJ, Brazil. Analysis revealed details of the use of anterior parts of the pectoral fins which act as digging ‘hands’ to access infaunal prey items that are subsequently captured by oral suction feeding. Each pectoral fin has two distinct sections articulated separately on the pectoral girdle. The digging ‘anterior pectoral fin’ mainly consists of segmented and flexible fin rays but has an anterior robust unsegmented ray that provides an edge to the ‘hand’, allowing penetration of the substratum. The huge ‘posterior pectoral fins’ are supported by unsegmented rays. Most digging episodes involved one ‘hand’ and consisted of 1–7 cycles of movement with frequencies 1.15–3.74 cycles s−1. During a cycle, the ‘hand’ is moved forwards and medially above the substratum, then is twisted medially and simultaneously depressed so that the anterior unsegmented ray impacts and enters the substratum. The hand is then drawn backwards and laterally to disturb the substratum. To prevent upward pitching of the head during digging, the ‘posterior pectoral fins’ are both moved anteriorly and laterally to shift the centre of gravity forwards while the caudal and second dorsal fins continue to provide propulsive force.

Processing and Digestion of Press Juices from Different Fish Muscles; Temperature and Lyophilization Effects on Their Anti-Oxidative Properties

ABSTRACTPress juices (PJs) from seven, mostly underutilized, fish were tested for their anti-oxidative properties. The effects of thermal processing, freezing, and lyophilization of fresh PJs on these properties were investigated. Lyophilized samples were further subjected to in vitro digestion. It was concluded that thermal processing significantly affected only the ferric ions reducing ability, while freezing affected the anti-oxidative properties of only certain species. Lyophilized samples from Dactylopterus volitans and Trachinus draco were able to delay significantly the onset of hemoglobin-mediated oxidation. Finally, the exposure of the PJs to different pH values during in vitro digestion seemed to play an important role in their 1,1-diphenyl-2-picrylhydrazyl (DPPH)% inhibition ability.

Feeding habits and trophic status of Merluccius hubbsi along the northernmost limit of its distribution in the South-western Atlantic

AbstractStomach contents analysis and stable isotope results indicate M. hubbsi is a generalist predator that feeds mainly on demersal fishes, followed by crustaceans and cephalopods. Ontogenetic changes in diet were identified, with fish importance increasing in the diet with hake size. Smaller hake (<250 mm) fed mostly on the sepiolid Semirossia tenera (89.45%IRI) and engraulid fish (89.96%IRI). Mid-sized hake (250–300 mm) fed mainly on benthic fish such as Bellator brachychir (95.63%IRI) and euphausiids (56.46%IRI), while larger hake (>300 mm) fed heavily on Dactylopterus volitans (94.80%IRI) and occasionally on a variety of teleosts. Significant correlations between δ13C (P < 0.05), THg (P < 0.001) and hake size occurred, whereas no relationship was observed between δ15N and hake size or δ15N and total mercury. Signatures were lowest in smaller hake with a tendency of increasing with size. Smaller and larger hake were significantly different in δ13C. Differences regarding isotopic niche width were quantified for each size group; trophic diversity and trophic redundancy among them were negligible, but hake >300 mm possibly have a larger feeding plasticity due to the combination of prey from a wide trophic level range.

The carcinofauna found in stomach contents of the flying gurnard (Dactylopterus volitans) on the continental shelf of the Campos Basin, Brazil

ABSTRACTA total of 3109 crustaceans belonging to 50 taxa distributed in 42 families were found in 117 analysed stomachs of flying gurnard (Dactylopterus volitans). Samples were obtained in April 2008 by the R/V Gyre using a bottom trawl towed in 12 stations at 14–100 m depth on the continental shelf of the Campos Basin, Brazil. The carcinofauna was analysed and the order Calanoida (Copepoda) found to be the most important item in terms of relative abundance and frequency of occurrence, followed by the order Amphipoda (Peracarida), the infraorder Brachyura (Decapoda), the order Stomatopoda and the subclass Myodocopa (Ostracoda). In the order Calanoida, the species Pontellopsis cf. villosa (Pontellidae) represented 98.04% of total crustacean abundance. The diet of Dactylopterus volitans varied according to fish size, with higher diversity of Crustacea at smaller size classes, decreasing in larger fishes. A similar pattern regarding depth was obtained, with greater diversity of taxa in gurnard stomachs caught at shallower depths. Flying gurnard is considered a generalized carnivore of invertebrates, eating mobile macrobenthic organisms, such as crustaceans, and its diet varies with its life stage, without any specific group as its main food source.

Gross chemical profile and calculation of nitrogen-to-protein conversion factors for nine species of fishes from coastal waters of Brazil

The amino acid composition and contents of nitrogen, phosphorus, lipid, carbohydrate and protein were determined in muscles of Dactylopterus volitans, Genypterus brasiliensis, Mullus argentinae, Paralichthys patagonicus, Percophis brasiliensis, Pinguipes brasilianus, Rhizoprionodon lalandii, Rhizoprionodon porosus, and Urophycis cirrata. The samples showed low carbohydrate content (<3.5% dry weight in all species) and were rich in protein (>66% dry weight in all species). The percentage of total lipid varied widely among species, and M. argentinae showed the highest concentrations (16%). The percentage of nitrogen and phosphorus was high and similar among species, with overall average values of 13.3% and 1.2%, respectively. The amino acids composition was similar among the animals, with glutamic acid and lisine as the most abundant amino acid and histidine in low concentrations. Among species, the content of proteinaceous nitrogen was high, with an average of 96.8% of the total nitrogen. From data of total amino acid and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-toprotein conversion factors ranged from 5.39 to 5.98, with an overall average of 5.71. These findings showed that the traditional conversion factor of 6.25 overestimates the actual protein content and should be avoided.

ESPÉCIES, SEXOS E TAMANHOS DO CAMARÃO-ROSA, Farfantepenaeus spp., NO ESTADO DO RIO DE JANEIRO (BRASIL)

Este trabalho trata da ocorrência de espécies, sexos e tamanhos do camarão-rosa, em amostras de capturas na área de Cabo Frio (Rio de Janeiro – Brasil), realizadas entre julho/2000 e fevereiro/2001. Sob a denominação de camarão-rosa são conhecidas duas espécies do gênero Farfantepenaeus Burukovscky no sudeste do Brasil: F. brasiliensis (Latreille) e F. paulensis (Pérez-Farfante). Estas espécies e seus sexos são de difícil identificação nas amostragens feitas durante desembarques das capturas comerciais. A espécies F. brasiliensis predominou nas amostras, com 59,4% dos indivíduos – na área de Cabo Frio se encontra o limite norte da ocorrência de F. paulensis. Houve equilíbrio entre os sexos da primeira espécie, não observado com a segunda. As menores médias do comprimento do cefalotórax e do peso total, registradas para os machos de ambas as espécies eram esperadas, porque as fêmeas alcançam maiores tamanhos.

Proximate and biochemical characterization of burrito (Bachydeuterus auritus) and flying gurnard (Dactylopterus volitans).

With limited protein resources and depleting commercial fish species there is the need to improve utilization of some of the lesser known species which are underutilized, for example, big eye grunt (burrito), Bachydeuterus auritus, and the flying gurnard (Dactylopterus volitans), (other names Cephalocanthus volitans (local) Pampansre). This study was to characterize some of the proximate and biochemical properties of burrito and the flying gurnard so as to evaluate their potential for use in human nutrition and other value‐added products. Proximate and chemical analysis were determined by the methods of AOAC. Fatty acid profiles were determined following the method of Saaed and Howell (1999). Amino acid profiles for the species were determined according to Bidlingmeyer et al. (1987). The protein content of both the water soluble and salt soluble protein extracts of the fish species were determined by the Bradford Protein Assay method (Bradford 1976). Rancidity of the fish species was assessed by thiobarbituric acid reactive substances (TBARS) and Peroxide value (PV) as described by Saeed and Howell (1999). Burrito contained 18% protein, whereas the flying gurnard contained 22.3%. Calcium content was 296 mg/100 g for burrito and 185 mg/100 g for flying gurnard, whereas iron content was 4.1 mg/100 g and 1.0 mg/100 g for burrito and the flying gurnard, respectively. Palmitic acid (C16) was 27% and 14.3% for the flying gurnard and burrito, respectively. C17: 1ω8 was 3% in the flying gurnard and 0.2% in burrito. Oleic (C18:1ω9) was 17% in the flying gurnard and 6% in burrito. C20:4ω6 was 1.6% in the flying gurnard and 3% in burrito. Docosahexaenoic acid (C22:6ω3) was 4.9% in the flying gurnard and 4.0% in burrito. Both burrito and the flying gurnard are of high nutritional quality as they had a high protein content, good general amino acid profile and abundance of polyunsaturated fatty acids.

Characterization of the gelatin of the flying gurnard (Dactylopterus volitans) and its interaction with starch

Gelatin extracted from the skin of the flying gurnard (Dactylopterus volitans L,) was characterised and its interaction with cassava starch mixtures of different ratio concentrations was investigated by rheology and differential scanning calorimetry (DSC). Protein and moisture were the main proximate composition, whilst glycine was the main amino acid. The gelatin had high bloom (275 g) strength with high imino acids, proline and hydroxyproline, content of 217/1000 residues. Gelation temperatures increased as more starch is used in the mixtures, ranging from 19.0°C for gelatin to starch ratio 4:1 to 70.1°C for mixture 1:4. Inclusion of cassava starch also increased the elastic modulus of the gelatin phase. Therefore, gelatin from flying gurnard skin has a potential to serve as an alternative source of non-bovine or porcine gelatin for food applications.

Checklist of rocky reef fishes from the Currais Archipelago and Itacolomis Island, Paraná state, Brazil

The ichthyofauna of the rocky substrate of Currais Archipelago and Itacolomis Island (Paraná state, Brazil) was surveyed between October 2008 and August 2009 through visual census, using 40 m2 (20x2 m) band transects at an average depth of 6 m. A total of 14,210 individuals (66 species from 33 families) were observed in 336 band transects, covering an area of 13,440 m2. Stegastes fuscus, Abudefduf saxatilis, Haemulon aurolineatum and Malacoctenus delalandii were the most abundant species. “Carnivore” was the most species-rich category, and “Mobile Invertebrate Feeder” the most abundant. Nine species are added to the list of reef fishes of the Paraná state: Acanthurus coeruleus, Dactylopterus volitans, Epinephelus morio, Myrichthys breviceps, Ophioblennius trinitatis, Paraclinus spectator, Scorpaena brasiliensis, and Selene vomer.

Myxidium volitans sp. nov., a parasite of the gallbladder of the fish, Dactylopterus volitans (Teleostei: Triglidae) from the Brazilian Atlantic coast: morphology and pathology

Myxidium volitans sp. nov. (Myxozoa: Myxidiidae) parasitizing the hypertrophied green-brownish gallbladder of the teleost Dactylopterus volitans, collected in the Atlantic coast near Niterói, Brazil was described based on ultrastructural studies. The spores were fusiform, sometimes slightly crescent-shaped on average 21.7 ± 0.3 µm (mean ± standard deviation) (n = 50) long and 5.6 ± 0.4 µm (n = 30) wide. The spore wall was thin and smooth, comprising two equally-sized valves joined by a hardly visible sutural ridge. Spores containing two pyriform polar capsules (PC) (5.0 ± 0.4 × 2.3 ± 0.3 µm) (n = 30) are situated in each extremity of the spore. The PC wall was composed of hyaline layer (0.20-0.29 µm thick) and by a thin external granular layer. Each PC contains a polar filament (PF) with irregular arrangements that was projected from its apical region to the bases of PC and coiled laterally from bases to the tip of PC. Some regular striations and S-like structures in the periphery of the PFs with four-five irregular sections were observed. Based on the spore morphology, ultrastructural differences and the specificity of the host we describe this parasite as a new myxosporidian, named M. volitans sp. nov.

Feeding ecology of monkfish Lophius gastrophysus in the south-western Atlantic Ocean

The diet of the monkfish Lophius gastrophysus is described based on the analysis of stomach contents, for the south-western Atlantic from samples landed in the fishing port of Niteroi, Rio de Janeiro state, Brazil, from April 2004 to March 2006. Feeding intensity, measured as the presence or absence of contents in stomachs, and differences in the items' composition were analysed by sex, size-class and season. High feeding intensity predominated for females >32 cm and for males <31 cm. There was no seasonal pattern in the occurrence of full or empty stomachs. The most important category in the diet was fish with 25 identified species. Dactylopterus volitans showed the highest alimentary index value, mainly because of the feeding of juvenile monkfish. The second most important category was Mollusca, represented mainly by squid. No relationships between predator- and prey-lengths and weights were observed; but there was a tendency to consume light and small prey independently of the size of the monkfish.

A non-digging zoobenthivorous fish attracts two opportunistic predatory fish associates

Following behaviour among reef fishes involves mostly a digging nuclear species while foraging, which attracts opportunistic followers preying on the exposed organisms. The flying gurnard Dactylopterus volitans preys on benthic animals, mostly crustaceans and small fishes, scratching and probing the bottom with the inner rays of its pectoral fins. We recorded the flying gurnard being followed by two opportunistic predators, the yellow jack Caranx bartholomaei and the coney Cephalopholis fulva at Fernando de Noronha, off northeast Brazil. Albeit not actually digging the substrate, the flying gurnard acts as a nuclear species by exploring algae tufts and by its wandering near the boulders and ledges, disturbing and flushing out hidden animals which thus become available to predation.

Metazoários parasitos do coió Dactylopterus volitans (Linnaeus, 1758) (Osteichthyes: Dactylopteridae) do litoral do Estado do Rio de Janeiro, Brasil

Seventy-eigth specimens of Dactylopterus volitans (Linnaeus,1758) collected from the coastal zone of the State of Rio de Janeiro (21-23º S, 41-45º W), Brazil, from December 2002 to January 2003, were necropsied to study their metazoan parasites. Twenty-seven species of parasites were collected: 1 aspidogastrean, 15 digenean, 1 monogenean, 2 cestodes, 2 acantocephalan, 4 nematodes, 1 branquiuran, and 1 isopod. All parasite species were recorded by the first time in D. volitans. The acanthocephalan Rhadinorhynchus sp. was the most dominant species with the highest prevalence in the parasite community of D. volitans. Opecoeloides sp. showed positive correlation between the host total length and parasite prevalence, while Rhadinorhynchus sp. have a negative correlation between the host´s total length and prevalence. One pair of endoparasite species (Dinurus sp.- Lecithochirium sp.) showed positive covariation between their abundances. As other parasite communities of benthic fishes from Rio de Janeiro, the parasite community of D. volitans is apparently a little−ordered species complex, characterized by the dominance of the endoparasite species

Meek's Halfbeak, Hyporhamphus meeki, and Flying Gurnard, Dactylopterus volitans, captured in the Annapolis Basin, Nova Scotia

Meek's Halfbeak, Hyporhamphus meeki, and Flying Gurnard, Dactylopterus volitans, captured in the Annapolis Basin, Nova Scotia

On the Swimming Bladder and Flying Powers of Dactylopterus volitans

Dactylopterus volitans, the so-called “flying gurnard,” is not included by Günther in the genus Triglidæ, as its name might imply, but is assigned to the small allied family of Cataphracti.Günther diagnoses it as follows :—“Dactylopterus, no lateral line, pectoral fins very large, an organ of flight, with the upper portion detached and shorter, granular teeth in the jaws, none on the palate, air bladder divided into two lateral halves, each with a large muscle.”Before proceeding to describe in detail the swimming bladder and other anatomical peculiarities, it may be well to state, that the skull is provided with a superficial bony covering which projects backwards over the region of the “shoulder” in two flattened plates, each terminating in a spine (seen in fig. 2). Also that the first four vertebræ of the column have coalesced so as to form a rigid tube, the neural spines being united as a vertical plate, which for convenience I have termed the neural plate.