Appeltans W.,Flanders Marine Institute |
Appeltans W.,Intergovernmental Oceanographic Commission of UNESCO |
Ahyong S.T.,South Australian Museum |
Ahyong S.T.,University of New South Wales |
And 124 more authors.
Current Biology | Year: 2012
Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered. Results: There are ∼226,000 eukaryotic marine species described. More species were described in the past decade (∼20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are ∼170,000 synonyms, that 58,000-72,000 species are collected but not yet described, and that 482,000-741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7-1.0 million marine species. Past rates of description of new species indicate there may be 0.5 ± 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science. Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century. © 2012 Elsevier Ltd.
Achatz J.G.,University of Innsbruck |
Sterrer W.,Bermuda Natural History Museum
Zootaxa | Year: 2015
We describe two new species, Austrognathia glandifera and Austrognatharia orientis using observations on squeezed, live specimens as well as histological sections and transmission electron microscopy. The protonephridia of Austrognatharia orientis are composed of a terminal cell, a canal cell, and a nephroporus cell. The monociliated terminal cell constitutes the so-called filtration area. The canal cell harbors the lacunar system and the protonephridial duct, which is surrounded by six filamentous rods, which originate external to and in between the microvilli of the terminal cell and stretch along the entire length of the canal cell. The female copulatory organs of the investigated species are very different. Austrognathia glandifera has a bursa and a vagina whereas A. orientis only has a weakly defined bursal tissue and no detectable vagina. The bursa is divided into an anterior and a posterior part; at the anterior end a special area is formed by interdigitations of the cells of the bursal wall. The male copulatory organs in the Conophoralia are uniform, composed of an anterior, glandular portion consisting of a proximal part with medium-grained and a distal part with coarse-grained appearance and a penis that is delineated by a basal lamina and has an ejaculatory duct as well as a gonopore. Parenchymal cells are present and serve to embed the bursa and the male copulatory organ dorsolaterally. Our data on the fine structure of various tissues indicate that the Conophoralia are the "less derived" sister taxon of the Scleroperalia. Copyright © 2015 Magnolia Press.
Pascal P.-Y.,University of Trinidad and Tobago |
Bellemare C.,University of Trinidad and Tobago |
Sterrer W.,Bermuda Natural History Museum |
Boschker H.T.S.,Netherlands Institute of Ecology |
And 3 more authors.
Marine Ecology | Year: 2015
Haplognathia ruberrima is a cosmopolitan gnathostomulid species found in sulfur bacterial mats in mangroves in Guadeloupe (French West Indies). Haplognathia ruberrima presents a δ13C value lower than all measured meiofaunal grazers and lower than the available measured food sources of this environment. This low δ13C value can not be due to specific ingestion of 13C-depleted methanogenic bacteria because abundances of those bacteria are reduced in surficial and deep sediments as revealed by δ13C of bacterial fatty acid. According to scanning electron microscope observations, no bacterial ectosymbionts were observed at the surface of the gnathostomulids, and transmission electron microscope views revealed the absence of bacterial endosymbionts. Energy-dispersive X-ray spectroscopy analysis detected low levels of sulfur (0.32%±0.8) in biological tissues of H. ruberrima, confirming the absence of thioautotrophic bacterial symbionts in these animals. Consequently, the low δ13C value of H. ruberrima can not be due to the presence of sulfur-oxidizing symbionts but more probably to the selective and exclusive consumption of free-living, sulfur-oxidizing bacteria. © 2015 Blackwell Verlag GmbH.
Eddy C.,University of Massachusetts Dartmouth |
Pitt J.,Government of Bermuda |
Morris J.A.,National Oceanic and Atmospheric Administration |
Smith S.,Bermuda Natural History Museum |
And 2 more authors.
Marine Ecology Progress Series | Year: 2016
As a generalist and opportunistic predator, lionfish (Pterois volitans and P. miles) consume large quantities of juvenile reef fish and invertebrates, as well as the adults of small-bodied species. To better understand the impacts of these fishes upon invaded coral reef ecosystems, we describe the feeding habits of invasive lionfish in Bermuda based on stomach contents analysis, and the influence that environmental factors have on their diet via spatial and temporal changes in prey availability. Relative to other regions throughout the northwestern Atlantic, lionfish in Bermuda consume a greater proportion of crustaceans, and their diet appears to rely upon the relative abundance of available prey species. A poorly-known crustacean, the red night shrimp Cinetorhynchus rigens, is the species of greatest importance to the diet of Bermuda lionfish. Currently, herbivorous fishes do not make a major contribution to their diet, although the lionfish frequently target both ecologically (e.g. bluehead wrasse Thalassoma bifasciatum) and economically important species (e.g. Atlantic creolefish Paranthias furcifer). © C.E., J.P., S.S., G.G.-G., D.B., and the USA Government 2016.
Worsaae K.,Copenhagen University |
Sterrer W.,Bermuda Natural History Museum |
Kaul-Strehlow S.,University of Vienna |
Hay-Schmidt A.,Copenhagen University |
Giribet G.,Harvard University
PLoS ONE | Year: 2012
The interstitial environment of marine sandy bottoms is a nutrient-rich, sheltered habitat whilst at the same time also often a turbulent, space-limited, and ecologically challenging environment dominated by meiofauna. The interstitial fauna is one of the most diverse on earth and accommodates miniaturized representatives from many macrofaunal groups as well as several exclusively meiofaunal phyla. The colonization process of this environment, with the restrictions imposed by limited space and low Reynolds numbers, has selected for great morphological and behavioral changes as well as new life history strategies. Here we describe a new enteropneust species inhabiting the interstices among sand grains in shallow tropical waters of the West Atlantic. With a maximum body length of 0.6 mm, it is the first microscopic adult enteropneust known, a group otherwise ranging from 2 cm to 250 cm in adult size. Asexual reproduction by paratomy has been observed in this new species, a reproductive mode not previously reported among enteropneusts. Morphologically, Meioglossus psammophilus gen. et sp. nov. shows closest resemblance to an early juvenile stage of the acorn worm family Harrimaniidae, a result congruent with its phylogenetic placement based on molecular data. Its position, clearly nested within the larger macrofaunal hemichordates, suggests that this represents an extreme case of miniaturization. The evolutionary pathway to this simple or juvenile appearance, as chiefly demonstrated by its small size, dense ciliation, and single pair of gill pores, may be explained by progenesis. The finding of M. psammophilus gen. et sp. nov. underscores the notion that meiofauna may constitute a rich source of undiscovered metazoan diversity, possibly disguised as juveniles of other species. © 2012 Worsaae et al.
De Putron S.J.,Bermuda Institute of Ocean Sciences |
Smith S.R.,Bermuda Natural History Museum
Bulletin of Marine Science | Year: 2011
Planula release from the scleractinian coral Porites astreoides Lamarck, 1816 at a high-latitude reef in Bermuda primarily occurred in the summer months of July and August, when the average seawater temperature for the lunar cycle preceding planulation exceeded 26.5 °C. Within the reproductive season in Bermuda, optimal planulation temperatures for P. astreoides are narrow. The release of fewer planulae was correlated with higher temperatures and there was significant variation in reproductive effort in colonies collected from sites across the 18-km wide Bermuda lagoonal seawater temperature gradient during this 2-yr study. The annual reproductive period of this species lengthens with a decline in latitude, which corresponds to a decrease in the range of annual seawater temperatures. Reproductive effort, as measured by the percentage of the population that is reproductive and number of planulae released per colony, is similar or slightly higher in Bermuda compared to conspecifics at lower latitudes. However, the shortened reproductive season results in a lower overall annual reproductive effort in Bermuda. Lunar synchrony of planula release peaked a few days before the new moon, slightly earlier than conspecifics in Florida, which peak during the new moon. Colonies from the Inner Lagoon peaked in planula release a few days earlier than those from other zones. We attribute spatial variation in lunar periodicity of planula release to differences in the timing of fertilization or planula maturation that may be influenced by environmental factors such as temperature and turbidity. © 2011 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.
Kerbl A.,Copenhagen University |
Bekkouche N.,Copenhagen University |
Sterrer W.,Bermuda Natural History Museum |
Worsaae K.,Copenhagen University
BMC Evolutionary Biology | Year: 2015
Background: The microscopic worm group Lobatocerebridae has been regarded a 'problematicum', with the systematic relationship being highly debated until a recent phylogenomic study placed them within annelids (Curr Biol 25: 2000-2006, 2015). To date, a morphological comparison with other spiralian taxa lacks detailed information on the nervous and muscular system, which is here presented for Lobatocerebrum riegeri n. sp. based on immunohistochemistry and confocal laser scanning microscopy, supported by TEM and live observations. Results: The musculature is organized as a grid of longitudinal muscles and transverse muscular ring complexes in the trunk. The rostrum is supplied by longitudinal muscles and only a few transverse muscles. The intraepidermal central nervous system consists of a big, multi-lobed brain, nine major nerve bundles extending anteriorly into the rostrum and two lateral and one median cord extending posteriorly to the anus, connected by five commissures. The glandular epidermis has at least three types of mucus secreting glands and one type of adhesive unicellular glands. Conclusions: No exclusive "annelid characters" could be found in the neuromuscular system of Lobatocerebridae, except for perhaps the mid-ventral nerve. However, none of the observed structures disputes its position within this group. The neuromuscular and glandular system of L. riegeri n. sp. shows similarities to those of meiofaunal annelids such as Dinophilidae and Protodrilidae, yet likewise to Gnathostomulida and catenulid Platyhelminthes, all living in the restrictive interstitial environment among sand grains. It therefore suggests an extreme evolutionary plasticity of annelid nervous and muscular architecture, previously regarded as highly conservative organ systems throughout metazoan evolution. © 2015 Kerbl et al.
Wildish D.J.,Fisheries & Oceans Canada |
Smith S.R.,Bermuda Natural History Museum |
Loeza-Quintana T.,University of Guelph |
Radulovici A.E.,University of Guelph |
Adamowicz S.J.,University of Guelph
Journal of Natural History | Year: 2016
Five taxa of talitrid amphipods were found in the archipelago of Bermuda, of which three were recorded there for the first time. Four of these are supralittoral wrack generalists: Platorchestia monodi BOLD:AAB3402, (a unique Molecular Operational Taxonomic Unit according to the Barcode Index Number system), a related species recognized by molecular methods, Platorchestia platensis BOLD:AAA2949, Mexorchestia carpenteri carpenteri BOLD:AAC1491 and Tethorchestia antillensis; and one a terrestrial leaf-litter generalist: Talitroides alluaudi. A key is provided to discriminate between the formally described talitrids of Bermuda. Dispersal mechanisms from the American continent to Bermuda were considered for all taxa based on species distributions along the North American Atlantic coast and also investigated by molecular methods, using genetic population differentiation and haplotype network analysis based on the barcode region of cytochrome c oxidase subunit I gene. For P. monodi BOLD:AAB3402 the genetic results suggest that some dispersal events occurred before human colonization of Bermuda but are equivocal about the source population and therefore the direction of dispersal. Some very recent synanthropic dispersal is possible with this species. For the other two species studied genetically, P. platensis BOLD:AAA2949 and M. c. carpenteri BOLD:AAC1491, the small population samples analysed support dispersal to Bermuda from the American mainland, before human occupation of Bermuda, although the available sample size was limited for these species. The available limited direct, non-genetic evidence supports synanthropic transport for Talitroides alluaudi. Platorchestia monodi BOLD:AAB3402 is found in the same wrack habitat as P. platensis BOLD:AAA2949 on Bermuda, apparently without interbreeding. No evidence was found that driftwood specialist talitrids had become established in Bermuda. © 2016 Informa UK Limited, trading as Taylor & Francis Group