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— A cladistic analysis of the eighteen species of Spanish mackerels (Scomberomorus) was conducted using the double-lined mackerel (Grammatorcynus) as the outgroup. Based on fifty-eight osteological and morphological characters, six species groups are recognized. Comparisons of the cladogram for the regalis species group were made with a cladogram of the nine species of parasitic copepods that infest the six members of the regalis group. Incongruences were analyzed. The parasite tree was then “forced” onto the host cladogram to determine which evolutionary events of the parasites could be explained by evolutionary events of the hosts. Hypotheses of coevolution are supported in some cases, hypotheses of dispersal are proposed in others.

This part completes the review of the largest and economically richest order of fishes, Perciformes, begun in Part 3. It includes 12 suborders with keys and brief descriptions to 230 species, and information on their ecology and distribution.

Bluefin tunas have been fished sustainably for 2,000 years, but the recent demand for sashimi and sushi has led to the incredible price of $3 million for one Pacific Bluefin at the celebratory firs...

High market values have incentivized extensive fisheries for Pacific bluefin tuna ( Thunnus orientalis , see the photo), a species whose longevity, commercial value, and long generation time make it particularly susceptible to overfishing ( 1 , 2 ). Today, the population of Pacific bluefin tuna stands at an estimated 2.6% of prefished levels ( 1 ). Yet, knowledge of its basic life history is incomplete. Recent studies ( 3 , 4 ) suggest that the fundamental distribution of Pacific bluefin across the North Pacific has been misunderstood. The results underscore the need for basic movement ecology information to assist science-based fisheries management.

Nature Ecology & Evolution 1, 0170 (2017); published 26 May 2017; corrected 12 June 2017. In the original version of this Article, the European Commission was mistakenly included as an affiliation for Christos D. Maravelias. His contribution to this work was exclusively completed while at the Hellenic Centre for Marine Research.

The greater Caribbean biogeographic region covered in this report (representing 38 countries and territories) encompasses an outstanding marine bony shorefish richness of approximately 1,360 species, with many (53%) being endemic. This report provides an overview of the conservation status of greater Caribbean shorefishes, with detailed information available through the IUCN Red List, and gives recommendations.

—Toadfishes (Batrachoidiformes) are benthic fishes often burying in the sand or under rocks that occur worldwide in tropical to temperate marine and brackish waters. The Batrachoididae, the...

Hollardia hollardi (Reticulate Spikefish) is reported from two specimens caught in lobster traps along the southern edge of Georges Bank, far north of its previously known northern distribution from southern Florida, the Bahamas, and Bermuda.

Belone is distinguished from other genera of Belonidae mostly because of its complete cephalic sensory system, presence of gill rakers, vomerine teeth, and the pattern of its dentition. This eastern North Atlantic genus contains two extant species and at least three described fossil species from Lower Oligocene and Upper Miocene formations in Europe. †Belone countermani, sp. nov., a new species of needlefish from the Tortonian Upper Miocene St. Marys Formation of Calvert Cliffs (Maryland, U.S.A.), is described herein based on a well-preserved three-dimensional associated pair of upper and lower jaws. This rostrum represents the only record of this genus in the western North Atlantic Ocean. †Belone countermani is characterized by a unique dental pattern on the dentary. The dentary commissural region is filled with several rows of small accessory teeth (five to seven) that gradually decrease in number of rows; along the symphysial region there is one inner row of conical teeth and one external row ...

The Red List of marine bony fishes of the Eastern Central Atlantic (ECA) is a review of the conservation status of all native marine bony fishes in ECA according to the global Categories and Criteria of the IUCN Red List of Threatened Species. It identifies those species that are threatened with extinction at the global level and occur within the ECA region. This comprehensive assessment, which is the first of its kind in the ECA, aims to provide improved knowledge of species presence and extinction risk status for the purposes of guiding conservation actions and improved policies for these species both globally and regionally.

Validity of the largest size accounts is not well documented and most published accounts of body colora- tion describe dead specimens lacking scales instead of the color of freshly caught opah. Maximum length is at least 163 cm fork length and maximum weight about 89 kg. The body color of fresh specimens is vermilion with white spots.

The International Commission for the Conservation of Atlantic Tunas (ICCAT) spent the past 8 years and more than US$15 million to improve scientists' understanding of Atlantic bluefin and their management ([ 1 ][1]). Unfortunately, this year's long-awaited stock assessment produced more questions

This is a rebuttal to a publication by John C. Briggs in the April 2008 issue of Fisheries in which he suggested introducing fishes and invertebrates from the North Pacific into the North Atlantic to increase diversity toward improving fisheries in the latter. We argue otherwise for reasons that Briggs downplayed or never considered. Using examples of introductions within the Pacific and the Atlantic, and movements of species from the Pacific to the Atlantic, we provide a record of failures and damage or dangers to native species from the few introductions that became successful. We argue that a lack of diversity of fishes and invertebrates in the North Atlantic versus that of the North Pacific is not the problem to be corrected by introductions as Briggs suggested. A record of overfishing and management policies is the problem in the North Atlantic. Introductions from the North Pacific to the North Atlantic are not worth the costs or the environmental risks involved.

Dissection and histological analyses revealed the swimbladder of Hemiramphus far and H. robustus to comprise a matrix of discrete, gas-filled vesicles of 1–6 mm in diameter. The vesicles are not richly vascular and no discrete capillary bed organs were found. The anterior and posterior ends of the swimbladder have asymmetric projections that extend rostrad and caudad, respectively. These projections and some surrounding fatty tissue contain what we term protovesicles, which have thick walls that we infer expand to become the thin-walled vesicles of the main vesicular swimbladder. Dissection of museum specimens of other species of Hemiramphus and Oxyporhamphus convexus confirmed the presence of a vesicular swimbladder. However, examination of museum specimens of other hemiramphids, including O. micropterus, and flyingfishes revealed only a simple sac-like swimbladder. Presence of this unusual swimbladder in two genera within the same family is indicative of a strong synapomorphy that, in conjuncti...

We have previously documented multiple, independent origins of placentas in the fish family Poeciliidae. Here we summarize similar analyses of fishes in the family Zenarchopteridae. This family includes three live-bearing genera. Earlier studies documented the presence of superfetation, or the ability to carry multiple litters of young in different stages of development in the same ovary, in some species in all three genera. There is also one earlier report of matrotrophy, or extensive postfertilization maternal provisioning, in two of these genera. We present detailed life-history data for approximately half of the species in all three genera and combine them with the best available phylogeny to make inferences about the pattern of life-history evolution within this family. Three species of Hemirhamphodon have superfetation but lack matrotrophy. Most species in Nomorhamphus and Dermogenys either lack superfetation and matrotrophy or have both superfetation and matrotrophy. Our phylogenetic analysis shows that matrotrophy may have evolved independently in each genus. In Dermogenys, matrotrophic species produce fewer, larger offspring than nonmatrotrophic species. In Nomorhamphus; matrotrophic species instead produce more and smaller offspring than lecithotrophic species. However, the matrotrophic species in both genera have significantly smaller masses of reproductive tissue relative to their body sizes. All aspects of these results are duplicated in the fish family Poeciliidae. We discuss the possible adaptive significance of matrotrophy in the light of these new results. The two families together present a remarkable opportunity to study the evolution of a complex trait because they contain multiple, independent origins of the trait that often include close relatives that vary in either the presence or absence of the matrotrophy or in the degree to which matrotrophy is developed. These are the raw materials that are required for either an analysis of the adaptive significance of the trait or for studies of the genetic mechanisms that underlie the evolution of the trait.

The 40 life history, myological, and osteological characters that Tibbetts (1992) used in his study of the hemiramphids are evaluated for both saury genera (Cololabis and Scomberesox) to determine if the Scomberesocidae are more closely related to the Zenarchopteridae, to the needlefishes (Belonidae), or to the halfbeaks (Hemiramphidae) and flyingfishes (Exocoetidae). Data were analyzed using PAUP*, and eight equally parsimonious trees were found (70 steps, CI 0.814, RI 0.938). This analysis indicates that sauries are most closely related to needlefishes, supporting the historical concept of the superfamily Scomberesocoidea as a monophyletic assemblage. A caudal displacement of the origin of the retractor dorsalis muscle is a tentative additional synapomorphy for all four saury species. Zenarchopteridae is strongly supported as a valid family sister to the Scomberesocoidea (decay index = 19, bootstrap = 100). Resolution of the internal structure of the Belonidae and the Hemiramphidae requires the identification of additional characters and examination of a greater number of taxa.

To investigate jaw evolution in beloniform fishes, we reconstructed the phylogeny of 54 species using fragments of two nuclear (RAG2 and Tmo-4C4) and two mitochondrial (cytochrome b and 16S rRNA) genes. Our total molecular evidence topology refutes the monophyly of needlefishes (Belonidae) and halfbeaks (Hemiramphidae), but supports the monophyly of flyingfishes (Exocoetidae) and sauries (Scomberesocidae). Flyingfishes are nested within halfbeaks, and sauries are nested within needlefishes. Optimization of jaw characters on the tree reveals a diverse array of evolutionary changes in ontogeny. During their development, needlefishes pass through a "halfbeak" stage that closely resembles the adult condition in the hemiramphid halfbeaks. The reconstruction of jaw transitions falsifies the hypothesis that halfbeaks are paedomorphic derivatives of needlefishes. Instead, halfbeaks make up a basal paraphyletic grade within beloniforms, and the needlefish jaw morphology is relatively derived. The parallel between needlefish ontogeny and beloniform phylogeny is discussed, and clades amenable to future morphological analysis are proposed.

Spinoid scales appear early in the development of Swordfish, Xiphias gladius, and are first discernable in the larval stage. Scales vary in form between two principal types: small single and multispined scales and large multispined scales. Unlike the typical teleostean condition, Xiphias scales are attached along their base, not at their proximal end within scale pockets. Scales persist in juveniles and adults, that is, scales are not shed or resorbed. Scales become more deeply embedded within the dermis as the dermis thickens in ontogeny; consequently only the tips of spines protrude through the dermis of adults. A network of mucous canals with regularly spaced pores to the exterior develop in the dermis of adults, and the mucus produced further insulates scales from the surface of the integument. The ontogeny of the squamation of Xiphias differs from that of the related Istiophoridae.

The New World clade of needlefishes (Belonidae) includes species distributed along the Pacific and Atlantic coasts of the Americas and in freshwater basins of Central and South America. Phylogenetic relationships among 13 species of the group were assessed based on data from two nuclear genes (RAG2 and Tmo-4C4), two mitochondrial genes (cytochrome b and 16S rRNA), and a small suite of morphological characters. In general, there was concordance between separate analyses of nuclear and mitochondrial characters, and RAG2 was found to be a particularly useful gene for phylogeny reconstruction. Morphology supported an alternative phylogenetic pattern, but this was probably a result of the small number of characters and the lack of a thorough anatomical survey. The total evidence hypothesis divides the group into two major clades. In one, Pseudotylosurus from freshwater in South America is most closely related to a pair of Strongylura species from the western and eastern Atlantic; in the other, Potamor...

Sequence variation in the mitochondrialCytochrome b (Cytb) gene was assayed infour of six extant Bermuda killifishpopulations, representing two endemic species,to test taxonomic and phylogenetic hypothesesand reconstruct colonization history. Twodivergent (4.6%) haplotypes were detected; oneis identical to the Georgia 2c haplotype ofF. heteroclitus and is fixed in threeeastern populations: Lover's Lake (F.relictus), Mangrove Lake (F. bermudae),and Walsingham Pond. The second is fixed andrestricted to a western population, Evan'sPond. Likelihood and parsimony cytochrome btrees recognize a Bermuda Fundulus / F. heteroclitus clade in which the Evan's Pondhaplotype is basal. Phylogenies and haplotypedivergence indicate at least two Bermudacolonizations, the more recent involvingtransfer of the Georgia 2c haplotype. Enforcing Bermuda killifish monophyly, aspredicted from a single colonization event,does not increase tree length significantly;i.e., the trees also are consistent with asingle colonization. However, divergencebetween the Evan's Pond haplotype and the F. bermudae / F. relictus / Georgia 2chaplotype (4.6%) far exceeds the maximumdivergence among all F. heteroclitus,F. bermudae, and F. heteroclitushaplotypes (1.2%) and argues for independentcolonizations. Alternatively, recentintroduction of F. heteroclitus couldaccount for occurrence of the GA2c haplotype inBermuda but does not explain the presence ofthe genetically divergent Evans' Pondhaplotype. Cytb sequences areuninformative of the taxonomic status ofBermuda endemics, F. bermudae and F.relictus, but support recognition of theEvan's Pond population as an evolutionarilysignificant unit within the F. heteroclitus group.

Fishing can change the biological diversity of an ecosystem substantially, and determining the effects of fishing on marine biodiversity requires a variety of data, chief among them the proper identification of organisms. Because identification of all organisms in an ecosystem is not currently possible, target taxonomic groups (taxa) must be selected. The current status of taxonomic information varies greatly among taxa and among geographic areas within taxa. Problems include nomenclature, diagnoses, and determination of taxonomic relationships. We provide examples of a variety of these problems. We then propose a series of criteria for evaluating available taxonomic information in determining the potential reliability of species identification, including recency and comprehensiveness of revisionary studies, methods used for systematic and phylogenetic studies, adequacy of documentation, and evidence of peer review. When the goal is to explore biodiversity, these criteria must be used differently from when measuring and monitoring biodiversity.

The population ofScomber from the Red Sea and northern Indian Ocean (gulfs of Aden and Oman) is identified asS. australasicus rather thanS. japonicus based on having 30–33 vs. 26–29 interneural bones under the first and second dorsal fins and the combination of interneural bone counts of 16–20 under the first dorsal fin (vs. 13–16) and first dorsal fin spine counts of 10–13 (vs. 9–10). These are the best morphological characters to distinguish these two species. This change in identification constitutes a major range extension forS. australasicus which was thought to be restricted to the Pacific Ocean and the southeastern Indian Ocean around Western Australia.

Collecting biological specimens for scientific studies came under scrutiny when B. A. Minteer et al. [“Avoiding (re)extinction,” Perspectives, 18 April, p. [260][1]] suggested that this practice plays a significant role in species extinctions. Based on a small number of examples (rare birds

Systematists study and name the diverse forms of life and determine the evolutionary relationships among them. Increased interactions are needed between systematists and fishery scientists so systematists can obtain the material they need to study, and systematic problems of importance to fishery scientists can be resolved. The current shortage of systematists in some taxonomic groups, such as many invertebrate taxa, requires cooperative efforts by systematists and fishery scientists to train more specialists. Existing fishery sampling programs can aid in monitoring and understanding biological diversity at relatively little additional cost by expanding collecting efforts to include more taxa. The resulting voucher material serves to document the presence of a given species in time and space, and these specimens can be used for baselines of such things as heavy metals, pesticides, and parasite loads. Systematists need to translate their technical papers into practical guides and keys that can be ...

DNA barcoding is a method promising fast and accurate identification of animal species based on the sequencing of the mitochondrial c oxidase subunit (COI) gene. In this study, we explore the prospects for DNA barcoding in one particular fish group, the billfishes (suborder Xiphioidei--swordfish, marlins, spearfishes, and sailfish). We sequenced the mitochondrial COI gene from 296 individuals from the 10 currently recognized species of billfishes, and combined these data with a further 57 sequences from previously published projects. We also sequenced the rhodopsin gene from a subset of 72 individuals to allow comparison of mitochondrial results against a nuclear marker. Five of the 10 species are readily distinguishable by COI barcodes. Of the rest, the striped marlin (Kajikia audax) and white marlin (K. albida) show highly similar sequences and are not unambiguously distinguishable by barcodes alone, likewise are the three spearfishes Tetrapturus angustirostris, T. belone, and T. pfluegeri. We discuss the taxonomic status of these species groups in light of our and other data, molecular and morphological.

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world’s vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species. Fil: Hoffmann, Michael. International Union for Conservation Nature; Suiza Fil: Hilton Taylor, Craig. Species Programme; Reino Unido Fil: Angulo, Ariadne. Species Programme; Reino Unido Fil: Böhm, Monika. The Zoological Society Of London; Reino Unido Fil: Brooks, Thomas M.. University of the Philippines Los Baños; Filipinas Fil: Lavilla, Esteban Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina Fil: Tognelli, Marcelo Fabio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentina Fil: Baldi, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Lavilla, Esteban Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina Fil: Blanc, Julian J.. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina Fil: Lichtenstein, Gabriela. Secretaría de Cultura de la Nación. Dirección Nacional de Cultura y Museos. Instituto Nacional de Antropología y Pensamiento Latinoamericano; Argentina Fil: Valenti, Sara V.. Universidad Nacional del Comahue; Argentina Fil: Williamson, Elizabeth A.. University of Stirling; Reino Unido Fil: Xie, Feng. Chinese Academy of Sciences; República de China Fil: Young, Bruce E.. Stony Brook University; Estados Unidos Fil: Akçakaya, H. Resit. African Elephant Specialist Group; Kenia Fil: Leon Bemu. Wildlife Conservation Society; Estados Unidos Fil: Blackburn, Tim M.. Global Environment Facility; Estados Unidos Fil: Boitani, Luigi. Federal University of Minas Gerais; Brasil Fil: Dublin, Holly T.. Imperial College London; Reino Unido Fil: Claude Gascon,. IUCN; Suiza Fil: Georgina M. Mace. North of England Zoological Society; Reino Unido Fil: Lacher, Thomas E. Jr.. North of England Zoological Society; Reino Unido Fil: Mainka, Susan A.. Instituto Venezolano de Investigaciones Científicas; Venezuela Fil: McNeely, Jeffery A.. IUCN; Suiza Fil: Mittermeier, Russell A.. Conservation International; Estados Unidos Fil: McGregor Reid, Gordon. North of England Zoological Society; Reino Unido Fil: Rodriguez, Jon Paul. Instituto Venezolano de Investigaciones Científicas; Venezuela Fil: Rosenberg, Andrew A.. Conservation International; Estados Unidos Fil: Samways, Michael J.. Stellenbosch University; Sudáfrica Fil: Smart, Jane. IUCN; Suiza Fil: Stein, Bruce A.. National Wildlife Federation; Estados Unidos Fil: Stuart, Simon N.. Wildlife Park & Resort; Emiratos Arabes Unidos

NMNH ; NH-Vertebrate Zoology ; SDR ; affiliated agency staff ; NH-Invertebrate Zoology ; SISP ; Peer-reviewed

The jaw morphology of needlefishes (Beloniformes : Belonidae) passes through distinctive ontogenetic stages. When hatched, larvae have short jaws of equal length. The lower jaw first elongates to produce a halfbeak form, then the upper jaw elongates to produce the adult needlenose morphology. Onset and duration of the halfbeak stage vary among belonid species. We tested the hypothesis that heterochronic evolution produced this diversity in jaw morphology