From the light blue sky to the dark deep sea: Trophic and resource partitioning between epipelagic and mesopelagic layers in a tropical oceanic ecosystem.

The connection between epipelagic and deep-sea mesopelagic realms controls a variety of ecosystem processes including oceanic carbon storage and the provision of harvestable fish stocks. So far, these two layers have been mostly addressed in isolation and the ways they connect remain poorly understood. Furthermore, both systems are affected by climate change, exploitation of resources, and increasing pervasion of pollutants. Here we use bulk isotopes of δ13C and δ15N of 60 ecosystem components to evaluate the trophic linkage between epipelagic and mesopelagic ecosystems in warm oligotrophic waters. Additionally, we we conducted a comparison of isotopic niche sizes and overlaps across multiple species to evaluate how environmental gradients between epipelagic and mesopelagic ecosystems shape ecological patterns of resource use and competition between species. Our database comprises siphonophores, crustaceans, cephalopods, salpas, fishes, and seabirds. It also includes five zooplankton size classes, two groups of fish larvae, and particulate organic matter collected at different depths. Through this wide taxonomic and trophic variety of epipelagic and mesopelagic species, we show that pelagic species access resources originating from different food sources, mostly autotrophic-based (epipelagics) and microbial heterotrophic-based (mesopelagics). This leads to a sharp trophic dissimilarity between vertical layers. Additionally, we show that trophic specialization increases in deep-sea species and argue that food availability and environmental stability are among the main drivers of this pattern. Finally, we discuss how the ecological traits of pelagic species highlighted in this study can respond to human impacts and increase their vulnerability in the Anthropocene.

A new species of the hagfish genus Eptatretus (Myxinidae) from the Bahamas, western North Atlantic.

A new species of the hagfish genus Eptatretus (Myxinidae) is described based on two specimens (407-433 mm total length) collected off the northern Bahamas, between depths of 910 and 1153 m. The new species is distinguished from its congeners by having seven pairs of gill apertures well-spaced and arranged in a near straight line, a 3/2 multicusp pattern of teeth, 10-11 anterior unicusps, 50-51 total cusps, 12-14 prebranchial pores, 48-52 trunk pores, 79-84 total pores, and no nasal-sinus papillae. An identification key for the species of Eptatretus from the western Atlantic Ocean is also provided.

NEOTROPICAL FRESHWATER FISHES: A dataset of occurrence and abundance of freshwater fishes in the Neotropics.

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.

New records of rare deep-sea fishes (Teleostei) collected from off north-eastern Brazil, including seamounts and islands of the Fernando de Noronha Ridge.

Here we report on new data on the occurrence and distribution of rare deep-sea fishes (Teleostei) collected from off north-eastern Brazil, including seamounts and oceanic islands of the Fernando de Noronha Ridge (Rocas Atoll and Fernando de Noronha Archipelago). Collections were made by the French RV Antea during the ABRACOS (Acoustics along the BRAzilian COaSt) expeditions between 29 September and 21 October 2015, and 9 April and 10 May 2017. Occurrences of Photostylus pycnopterus (Alepocephalidae), Gigantura chuni (Giganturidae), Ahliesaurus berryi (Notosudidae), Benthalbella infans, Rosenblattichthys hubbsi, Scopelarchoides danae (Scopelarchidae), Scopelengys tristis (Neoscopelidae), Zu cristatus (Trachipteridae), Stylephorus chordatus (Stylephoridae) and Pseudoscopelus cordilluminatus (Chiasmodontidae) are reported for the first time or confirmed in the Brazilian Exclusive Economic Zone. Photostylus pycnopterus and G. chuni are also recorded for the first time in the western South Atlantic, whereas records of P. cordilluminatus are the first in the western Atlantic. Other records of rare species of those families are also reported and discussed.

Deep-sea anglerfishes (Lophiiformes: Ceratioidei) from off northeastern Brazil, with remarks on the ceratioids reported from the Brazilian Exclusive Economic Zone

The deep-sea anglerfishes of the suborder Ceratioidei (Lophiiformes) are represented by about 170 valid species with some of the most extraordinary morphological and reproductive adaptations among vertebrates, including extreme sexual dimorphism and male parasitism. Here we report on the diversity and distribution of rare ceratioids collected during the ABRACOS (Acoustics along the BRAzilian COaSt) expeditions off northeastern Brazil and the Fernando de Noronha Ridge (Rocas Atoll, Fernando de Noronha Archipelago, and associated seamounts). Chaenophryne ramifera, Oneirodes anisacanthus, O. carlsbergi, Gigantactis watermani, and unidentified specimens of Caulophryne, Dolopichthys, and Rhynchactis are recorded for the first time in the Brazilian Exclusive Economic Zone. Ceratias uranoscopus, Melanocetus johnsonii, and Chaenophryne draco have their distributions extended in Brazilian waters. Caulophryne, O. anisacanthus, and G. watermani are also recorded for the first time in the western South Atlantic. The specimen of G. watermani reported here represents the third known specimen of the species, and variations of its escal anatomy in relation to the holotype are described. Based on specimens examined and a review of records in the literature, 20 species of the Ceratioidei, in addition to unidentified species of Caulophryne, Dolopichthys, and Rhynchactis, are confirmed in the Brazilian Exclusive Economic Zone.(AU)

Os peixes-pescadores de profundidade da subordem Ceratioidei (Lophiiformes) são representados por cerca de 170 espécies válidas que apresentam algumas das adaptações anatômicas e reprodutivas mais extraordinárias entre os vertebrados, incluindo extremo dimorfismo sexual e parasitismo masculino. No presente estudo reportamos sobre a diversidade e distribuição de espécies raras de Ceratioidei coletadas durante as expedições ABRACOS (Acoustics along the BRAzilian COaSt) realizadas ao largo do nordeste do Brasil e na Cadeia de Fernando de Noronha (Atol das Rocas, Arquipélago de Fernando de Noronha e montes submarinos associados). Chaenophryne ramifera, Oneirodes anisacanthus, O. carlsbergi, Gigantactis watermani e espécimes não identificados de Caulophryne, Dolopichthys e Rhynchactis são registrados pela primeira vez na Zona Econômica Exclusiva brasileira. Ceratias uranoscopus, Melanocetus johnsonii e Chaenophryne draco tiveram suas distribuições estendidas em águas brasileiras. Caulophryne, O. anisacanthus e G. watermani também são registrados pela primeira vez no Atlântico Sul ocidental. O espécime de G. watermani reportado aqui representa o terceiro espécime conhecido da espécie, e variações anatômicas de sua esca em relação à do holótipo são descritas. Com base nos espécimes examinados e na revisão de registros na literatura, 20 espécies de Ceratioidei, além de espécies não identificadas de Caulophryne, Dolopichthys, and Rhynchactis, são confirmadas na Zona Econômica Exclusiva brasileira.(AU)

Trophic ecology, habitat, and migratory behaviour of the viperfish Chauliodus sloani reveal a key mesopelagic player.

Mesopelagic fishes are numerically the most important vertebrate group of all world's oceans. While these species are increasingly threatened by anthropogenic activities, basic biological knowledge is still lacking. For instance, major uncertainties remain on the behaviour, ecology, and thus functional roles of mesopelagic micronektivores, particularly regarding their interactions with physicochemical features. Here, we examine the trophic ecology, habitat, and migratory behaviour of the viperfish (Chauliodus sloani)-a poorly known and abundant deep-sea species-to further understand the ecology and thus functional role of mesopelagic micronektivores. Moreover, we explore how physical drivers may affect these features and how these relationships are likely to change over large oceanic areas. The viperfish heavily preys on epipelagic migrant species, especially myctophids, and presents spatial and trophic ontogenetic shifts. Temperature restricts its vertical distribution. Therefore, its trophodynamics, migratory behaviour, and functional roles are expected to be modulated by the latitudinal change in temperature. For instance, in most tropical regions the viperfish stay full-time feeding, excreting, and serving as prey (e.g. for bathypelagic predators) at deep layers. On the contrary, in temperate regions, the viperfish ascend to superficial waters where they trophically interact with epipelagic predators and may release carbon where its remineralization is the greatest.

First report of Lappetascaris lutjani Rasheed, 1965 (Nematoda, Ascaridoidea, Anisakidae) parasitizing Trachipterus arawatae (Pisces, Lampridiformes) on the Atlantic coast of Brazil.

New host and geographical records are reported for the nematode Lappetascaris lutjani Rasheed, 1965, parasitizing the marine fish Trachipterus arawatae Clark, 1881 in Brazilian waters. Morphometric data and illustrations of the parasites are included.

First report of Lappetascaris lutjani Rasheed, 1965 (Nematoda, Ascaridoidea, Anisakidae) parasitizing Trachipterus arawatae (Pisces, Lampridiformes) on the Atlantic Coast of Brazil

New host and geographical records are reported for the nematode Lappetascaris lutjani Rasheed, 1965, parasitizing the marine fish Trachipterus arawatae Clark, 1881 in Brazilian waters. Morphometric data and illustrations of the parasites are included