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Revision Of The Bathyal Fish Genus Benthocometes (Teleostei: Ophidiidae) With A New Species From Off Nw Australia
Abstract
The bathyal genus Benthocometes (Teleostei: Ophidiidae) is revised based on 29 specimens from the Atlantic Ocean and the Mediterranean Sea and one from off NW Australia. Examination of the Atlantic and Mediterranean material confirmed the synonomizing of the three Atlantic species, B. robustus, B. armatum and B. muraenolepis. The Australian specimen represents a new species, B. australiensis, differing from B. robustus in e.g. the number of long rakers on the anterior gill arch, the form of the palatine dentition and the predorsal and upper jaw lengths.
... The ophidiid genus Benthocometes Goode and Bean, 1896 includes two valid species, Benthocometes robustus (Goode and Bean, 1886) and Benthocometes australiensis Nielsen, 2010. The former is considered to be a senior synonym of Benthocometes armatus (Döderlein, 1886) and Benthocometes muraenolepis (Vaillant, 1888) (Bougis and Ruivo 1954;Nielsen 2010). ...
... The ophidiid genus Benthocometes Goode and Bean, 1896 includes two valid species, Benthocometes robustus (Goode and Bean, 1886) and Benthocometes australiensis Nielsen, 2010. The former is considered to be a senior synonym of Benthocometes armatus (Döderlein, 1886) and Benthocometes muraenolepis (Vaillant, 1888) (Bougis and Ruivo 1954;Nielsen 2010). Benthocometes robustus is known from off New Jersey, the United States of America, to Rio Grande do Sul, Brazil, along the Atlantic coasts of the Americas, including the Gulf of Mexico and Caribbean Sea (Haimovici et al. 1994;Nielsen 2010), and in the eastern Atlantic from off northwestern Africa and several localities in the Mediterranean Sea from off Spain to Cyprus (Nielsen 2010). ...
... The former is considered to be a senior synonym of Benthocometes armatus (Döderlein, 1886) and Benthocometes muraenolepis (Vaillant, 1888) (Bougis and Ruivo 1954;Nielsen 2010). Benthocometes robustus is known from off New Jersey, the United States of America, to Rio Grande do Sul, Brazil, along the Atlantic coasts of the Americas, including the Gulf of Mexico and Caribbean Sea (Haimovici et al. 1994;Nielsen 2010), and in the eastern Atlantic from off northwestern Africa and several localities in the Mediterranean Sea from off Spain to Cyprus (Nielsen 2010). Benthocometes australiensis is known only from the holotype from off northwestern Australia (Nielsen 2010). ...
A specimen (114.4 mm SL) of the rare ophidiid species, Benthocometes australiensis Nielsen, 2010, was collected from a deep-sea water intake at a depth of 320 m off Cape Muroto, Kochi Prefecture, Shikoku Island, Japan. The species is previously only known from the holotype trawled off northwestern Australia. Thus, the present specimen is the first record from the Northern Hemisphere and the second record of the species. New Japanese names “Suisei-ashiro-zoku” and “Muroto-suisei-ashiro” are proposed for Benthocometes and B. australiensis respectively.
... The robust cusk-eel Benthocometes robustus is a small size bathydemersal ophidiiform (15 cm max TL), with scattered records from bottom fishing in both the eastern and western Atlantic as well as the Mediterranean (Nielsen et al., 1999). With a short and stubby appearance, B. robustus is the only Atlantic species of the genus (Bougis and Ruivo, 1954;Nielsen, 2010), rendering identification from imagery data possible. ...
... The size classes of 5-10 cm (52%) and 10-15 cm (33%) comprised the majority of size measurements. Only on two occasions in early July on the Faial-Pico Channel southern slope, small size L. Nielsen (2010); measurements in mm, taken in fresh individuals; see Table 1 in Supplementary material for sample location). Specimens field codes (P1, P2 and P3) and museum codes in parenthesis (COLETA). ...
... The robust cusk-eel Benthocometes robustus is a small size bathydemersal ophidiiform (15 cm max TL), with scattered records from bottom fishing in both the eastern and western Atlantic as well as the Mediterranean (Nielsen et al., 1999). With a short and stubby appearance, B. robustus is the only Atlantic species of the genus (Bougis and Ruivo, 1954;Nielsen, 2010), rendering identification from imagery data possible. ...
... The size classes of 5-10 cm (52%) and 10-15 cm (33%) comprised the majority of size measurements. Only on two occasions in early July on the Faial-Pico Channel southern slope, small size L. Nielsen (2010); measurements in mm, taken in fresh individuals; see Table 1 in Supplementary material for sample location). Specimens field codes (P1, P2 and P3) and museum codes in parenthesis (COLETA). ...
Many fish species are well-known obligatory inhabitants of shallow-water tropical coral reefs but such associations are difficult to study in deep-water environments. We address the association between two deep-sea fish with low mobility and large sessile invertebrates using a compilation of 20 years of unpublished in situ observations. Data were collected on Northeast Atlantic (NEA) island slopes and seamounts, from the Azores to the Canary Islands, comprising 127 new records of the circalittoral Labridae Lappanella fasciata and 15 of the upper bathyal Ophiididae Benthocometes robustus. Observations by divers, remote operated vehicles (ROV SP, Luso, Victor, Falcon Seaeye), towed vehicles (Greenpeace) and manned submersibles (LULA, Nautile) validated the species association to cold water corals (CWC) and large hydrozoans. L. fasciata occurred from lower infralittoral (41. m) throughout the circalittoral, down to the upper bathyal at 398. m depth. Smaller fishes (< 10. cm) tend to form larger schools up to five individuals, with larger fishes (10-15. cm) occurring alone or in smaller groups at greater depths. The labrids favoured areas with large sessile invertebrates (> 10. cm) occurring at < 1 body-length, swimming inside or in close vicinity to the tallest and most complex three-dimensional structure in the field of observation. These included hydrozoans (Polyplumaria flabellata, Nemertesia antennina), CWC (e.g. Antipathella wollastoni, Acanthogorgia armata, Stichopathes sp.), and less frequently sponges (e.g. Pseudotrachya hystrix). B. robustus presented a coral-cryptic behavior, being recorded in the bathyal zone between 350 and 734. m depth, always inside CWC (e.g. Acanthogorgia spp., Antipathella spp., Callogorgia verticillata, Dendrophyllia alternata, Leiopathes spp.), and remaining within the coral branching. B. robustus were collected with baited traps providing biological information and dietary information reinforcing the trophic linkage between the CWC habitat and this predator. Gathered evidence renders CWC and hydroid gardens as Essential Fish Habitats for both species, being therefore sensitive to environmental and anthropogenic impacts on these Vulnerable Marine Ecosystems. The Mediterranean distribution of L. fasciata is extended to NEA seamounts and island slopes and the amphi-Atlantic distribution of B. robustus is bridged with molecular data support. Both species are expected to occur throughout the Macaronesia and Mediterranean island slopes and shallow seamounts on habitats with large sessile invertebrates.
... The intensive bottom trawling off northwestern Australia by the Research Vessel Southern Surveyor in 2007 revealed a number of new and rare ophidiiform fishes (Nielsen 2010(Nielsen , 2011. The present paper deals with one 39 mm SL adult male trawled at a depth of 392 m. ...
A new genus and species of bathyal bythitid fish (Teleostei: Ophidiiformes) is described based on a single specimen caught at a depth of 392 m in the Timor Sea off the coast of northwestern Australia. Timorichthys disjunctus gen. nov., sp. nov. differs from all other bythitid genera by the position of the anus midway between the tip of the snout and origin of the anal fin. The joined vertical fins and the type of intromittant organ furthermore place the new genus in the subfamily Bythitinae.
... De menor porte, Lucigadus ori atinge cerca de 24cm CT, foi descrito para a costa da África, mas possui ocorrências também na costa do Brasil e da Austrália, ocorrendo entre 120-1.210m (Smith 1968;Iwamoto & Williams 1999;Nielsen 2010) e comum entre 275 e 550m (Bernardes et al., 2005). ...
Macrourids are among the most abundant and diverse demersal fishes in all deep oceans, including the Southwestern Brazilian continental slope. Although not targeted by Brazilian fisheries, they suffer impact similar than the target species, being among the most discarded fishes by deep bottom trawling. Trophic Ecology: Data from research surveys and commercial fishing were used to analyze the trophic ecology of four species inhabiting the upper slope of southern Brazil: Coelorinchus marinii, Malacocephalus occidentalis, M. laevis and Lucigadus ori. For the two abundant ones, ontogenetic changes, seasonal variations, intra- and interspecific dietary overlap, parasite fauna and aspects of functional morphology are also described. C.marinii had an extremely diverse diet, preying infauna, epifauna, plankton, necton and carcasses. M.occidentalis fed on larger and nektonic prey, but also included crabs and carcasses in the diet. Both species showed ontogenetic shifts and seasonal variations in diet composition, both leading to changes in intra- and interspecific diet overlap patterns. Species showed quite distinct feeding anatomy and proportions of body with mouth size, reflecting on feeding strategies. There was little interspecific food overlap. In most cases when the diet was more similar there was a spatial segregation. The coexistence of these species appears to be facilitated by the development of different functional morphologies and feeding strategies. A considerable portion of the diet of these species is due to the consumption of carcasses of pelagic and mesopelagic organisms, and even insects, bypassing the benthic trophic web. Conservative (minimum) estimates of the mean weight of carcasses in diet ranged from 3 to 20%, increasing with the size of the predators and towards deeper waters. C.marinii showed a lower consumption of carcasses and a high proportion of mesopelagic fishes and cephalopods, however, the analysis of the feeding morphology and prey size leads to believe that most of these two groups of prey were consumed as carcasses. This source of food bypass the detritus food chains and connect the concentrations of macrourids to fluctuations in the abundance of epi and mesopelagic organisms and to oceanographic processes that increase their concentration and mortality (e.g. mesoscale anticyclonic eddies). Distribution, Biomass and Oceanography: Data from two seasonal bottom trawl surveys were used to provide information on distribution, abundances, densities, size- composition Malacocephalus occidentalis, M. and biomass estimates for seven species: Coelorinchus marinii, laevis, Lucigadus ori, Hymenocephalus billsam, Ventrifossa macropogon and V. mucocephalus. The total biomass was estimated in 5.5 and 8.3 kt respectively in winter-spring and summer-autumn. C.marinii and M.occidentalis ii comprised 98% of the biomass. For these two abundant species, surface maps were made with spawning areas, feeding index, sex and immature/mature ratios, and were related to oceanographic processes, providing insights on strategies and important processes regulating distribution and abundance patterns. Both species showed a marked seasonal variation in the extent and location of spawning areas. Most C.marinii females were mature (90%), suggesting an early maturation during pelagic phase and acquiring demersal habit just prior the onset of maturation, while M.occidentalis showed few matures females and settle to bottom well before maturity. Temperature rather than depth seems to be the main factor regulating the batimetric distribution of both species. We describe three processes responsible for distribution and abundance patterns found in these species. Different patterns of spatial segregation were found in both species, related with depth, sex and maturity. It is suggested that areas with high biomass Macrouridae (scavengers) are induced by zones of occurrence semi-permanent mesoscale processes (e.g. eddies). These processes increase productivity and enable large biomass of short-lived organisms found in the upper layers, and also increase the concentration, mortality and availability of carcasses, favoring scavenger predators. These processes may be responsible for inconsistencies in biomass of megafauna and macrofauna found in some studies, where biomass of megafauna was of the same order of magnitude or larger than macrofauna, contradicting the Eltonian principle. It is suggested that future studies attempt to relate mesoscale processes with the biomass of potential short-lived prey in surface waters and higher biomass of scavengers. This work highlights the importance of the study of ocean dynamics, combining biological and oceanographic observations, trying to understand the role of mesoscale physical processes on the distribution and abundance patterns of species.
... De menor porte, Lucigadus ori atinge cerca de 24cm CT, foi descrito para a costa da África, mas possui ocorrências também na costa do Brasil e da Austrália, ocorrendo entre 120-1.210m (Smith 1968;Iwamoto & Williams 1999;Nielsen 2010) e comum entre 275 e 550m (Bernardes et al., 2005). ...
Macrourids are among the most abundant and diverse demersal fishes in all deep oceans, including the Southwestern Brazilian continental slope. Although not targeted by Brazilian fisheries, they suffer impact similar than the target species, being among the most discarded fishes by deep bottom trawling. Trophic Ecology: Data from research surveys and commercial fishing were used to analyze the trophic ecology of four species inhabiting the upper slope of southern Brazil: Coelorinchus marinii, Malacocephalus occidentalis, M. laevis and Lucigadus ori. For the two abundant ones, ontogenetic changes, seasonal variations, intra- and interspecific dietary overlap, parasite fauna and aspects of functional morphology are also described. C.marinii had an extremely diverse diet, preying infauna, epifauna, plankton, necton and carcasses. M.occidentalis fed on larger and nektonic prey, but also included crabs and carcasses in the diet. Both species showed ontogenetic shifts and seasonal variations in diet composition, both leading to changes in intra- and interspecific diet overlap patterns. Species showed quite distinct feeding anatomy and proportions of body with mouth size, reflecting on feeding strategies. There was little interspecific food overlap. In most cases when the diet was more similar there was a spatial segregation. The coexistence of these species appears to be facilitated by the development of different functional morphologies and feeding strategies. A considerable portion of the diet of these species is due to the consumption of carcasses of pelagic and mesopelagic organisms, and even insects, bypassing the benthic trophic web. Conservative (minimum) estimates of the mean weight of carcasses in diet ranged from 3 to 20%, increasing with the size of the predators and towards deeper waters. C.marinii showed a lower consumption of carcasses and a high proportion of mesopelagic fishes and cephalopods, however, the analysis of the feeding morphology and prey size leads to believe that most of these two groups of prey were consumed as carcasses. This source of food bypass the detritus food chains and connect the concentrations of macrourids to fluctuations in the abundance of epi and mesopelagic organisms and to oceanographic processes that increase their concentration and mortality (e.g. mesoscale anticyclonic eddies). Distribution, Biomass and Oceanography: Data from two seasonal bottom trawl surveys were used to provide information on distribution, abundances, densities, size- composition Malacocephalus occidentalis, M. and biomass estimates for seven species: Coelorinchus marinii, laevis, Lucigadus ori, Hymenocephalus billsam, Ventrifossa macropogon and V. mucocephalus. The total biomass was estimated in 5.5 and 8.3 kt respectively in winter-spring and summer-autumn. C.marinii and M.occidentalis ii comprised 98% of the biomass. For these two abundant species, surface maps were made with spawning areas, feeding index, sex and immature/mature ratios, and were related to oceanographic processes, providing insights on strategies and important processes regulating distribution and abundance patterns. Both species showed a marked seasonal variation in the extent and location of spawning areas. Most C.marinii females were mature (90%), suggesting an early maturation during pelagic phase and acquiring demersal habit just prior the onset of maturation, while M.occidentalis showed few matures females and settle to bottom well before maturity. Temperature rather than depth seems to be the main factor regulating the batimetric distribution of both species. We describe three processes responsible for distribution and abundance patterns found in these species. Different patterns of spatial segregation were found in both species, related with depth, sex and maturity. It is suggested that areas with high biomass Macrouridae (scavengers) are induced by zones of occurrence semi-permanent mesoscale processes (e.g. eddies). These processes increase productivity and enable large biomass of short-lived organisms found in the upper layers, and also increase the concentration, mortality and availability of carcasses, favoring scavenger predators. These processes may be responsible for inconsistencies in biomass of megafauna and macrofauna found in some studies, where biomass of megafauna was of the same order of magnitude or larger than macrofauna, contradicting the Eltonian principle. It is suggested that future studies attempt to relate mesoscale processes with the biomass of potential short-lived prey in surface waters and higher biomass of scavengers. This work highlights the importance of the study of ocean dynamics, combining biological and oceanographic observations, trying to understand the role of mesoscale physical processes on the distribution and abundance patterns of species.
Cusk-eels of the order Ophidiiformes are a morphologically diverse assemblage of eel-like, elongate, posteriorly tapering percomorph fishes that occur worldwide in marine waters, from tropical reef areas to the deep sea. The about 400 extant and fossil species included in the ophidiiform clade are arranged into two main lineages, Bythitoidei and Ophidioidei, based on reproductive biology and the position of the anterior nostrils. The anatomy and phylogenetic relationships of these fishes are largely unknown, and the fossil record has not provided substantial information about the earliest phases of their evolutionary history. †Pastorius methenyi, new genus and species, the oldest member of the Ophidiiformes based on articulated skeletal remains, is described herein based on a single specimen collected from the Campanian-Maastrichtian organic-rich laminated limestone of the Liburnica Formation outcropping near the village of Trebiciano, north-eastern Italy. The comparative analysis of osteological and meristic features indicates that †Pastorius methenyi is characterized by at least one of the probable ophidiiform synapomorphies (exclusion of the supraoccipital from the posterior cranial margin by substantial posterodorsal extension of the exoccipitals) and exhibits a unique combination of characters, including a posteriorly broadly expanded maxilla; supramaxilla present; eight branchiostegals; 39 vertebrae; first neural spine shorter than those following; neural arch of first vertebra feebly connected to the first vertebral centrum though a narrow pedestal of bone; anterior abdominal vertebrae ostensibly lacking expanded ribs; caudal skeleton with ostensibly fused first preural, first ural centrum, first uroneural, and ventral hypural plate, and ostensibly fused second ural centrum and dorsal hypural plate, autogenous parhypural, and two epurals; caudal fin free, with 13 rays; a single ossified supraneural located in front of the second neural spine; and notably reduced number of dorsal- and anal-fin rays. †Pastorius is placed as the sister-group of all recent bythitoids, even if some features might indicate that it represents the sister-group of all ophidiiforms. †Pastorius provides the first unequivocal evidence that percomorphs with very elongate and compressed bodies were in existence in the Cretaceous, indicating that this group was characterized by a very high disparity and a vast diversification of bodyplans well before the Cretaceous-Paleogene extinction. © 2015 by the American Society of Ichthyologists and Herpetologists.
Ninety-three species of bony fishes were caught in 4 seasonal bottom-trawl surveys carried out between July 1986 and May 1987 on the outer shelf and upper slope (124 to 587 m depth) along the southern Brazilian coast (30°40' to 34"30' S). On the outer shelf (< 179 m), the demersal-pelagic species Trichiurus lepturus, Trachurus lathami, Cynoscion guatucupa, Scomber japonicus, and Thyrsitops lepidopoides predominated and also to a lesser degree the demersal benthonic Umbrina canosai and Mullus argentinae. Antiyonia capros and Priacanthus arenatus were found associated with the relic coral hard bottoms of the shelf break (180 to 249 m). Further offshore, the demersal-pelagic species Ariomma bondi and Zenopsis conchifera and the demersal benthonic species Polyprion ameri-canus and Helicolenus lahillei were abundant, both associated with rocky bottoms. The macrourids Coelorinchus marinii and Malacocephalus occidentalis characterized deep-water hauls p 4 5 0 m). Frequent and widespread, but less abundant in the catch, were Polymixia lowei, Urophycis mystacea and Merluccius hubbsi. Mean total catch (kg h-') decreased 6-fold and the number of species by more than half along the depth range, with a sharp step at 350 m. Both catch and number of species were slightly higher in the winter cruises. Most species occurred in both winter and summer-autumn cruises, but, with increasing depth, the relative abundance of species that occur year-round decreased, whereas fishes that occur mostly in winter increased. The catch of demersal-pelagic fish decreased sharply below 350 m and differed little among seasons; catches of demersal-benthonic fish were more evenly distributed across the depth range and were larger in winter and spring. The high number of species on the shelf break may be attributable to the higher variety of soft and consolidated substrates and the overlapping of different water masses along the water column. The north-south shift of the western boundary of the Subtropical Convergence appears to be mainly responsible for the seasonal changes in abundance of the species.