DOCSLIB.ORG

Copepoda, Siphonostomatoida, Pandaridae) Infesting the Goblin Shark Mitsukurina Owstoni Jordan, 1898 in Japanese Waters

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Copepoda, Siphonostomatoida, Pandaridae) Infesting the Goblin Shark Mitsukurina Owstoni Jordan, 1898 in Japanese Waters ECHTHROGALEUS MITSUKURINAE SP. NOV. (COPEPODA, SIPHONOSTOMATOIDA, PANDARIDAE) INFESTING THE GOBLIN SHARK MITSUKURINA OWSTONI JORDAN, 1898 IN JAPANESE WATERS BY KUNIHIKO IZAWA1) Izawa Marine Biological Laboratory, 795-16 Kannonji, Tsu, Mie 514-0062, Japan ABSTRACT Echthrogaleus mitsukurinae sp. nov. (Copepoda, Siphonostomatoida, Pandaridae) is described based on a female recovered from the body surface of the goblin shark, Mitsukurina owstoni Jordan, 1898, captured on the slope of the Tokyo Canyon at about 400 m depth in Tokyo Bay, Japan. This new species is easily distinguishable from all its congeners in having the following unique features in the female: (1) the lateral lobes of the cephalothorax and the lateral plates of pediger 2 are devoid of marginal membranes, (2) the dorsal plates of pediger 4 have a smooth margin, (3) the posterolateral lobes of the genital complex are widely curved medially and overlap each other across the midline, (4) legs 2 and 3 have 3-segmented endopods, and (5) leg 4 has an incompletely 2-segmented exopod. RÉSUMÉ Echthrogaleus mitsukurinae nov. sp. (Copepoda, Siphonostomatoida, Pandaridae) est décrit à partir d’une femelle prélevée à la surface du corps du requin lutin, Mitsukurina owstoni Jordan, 1898, capturé sur la pente du Tokyo Canyon à environ 400 m de profondeur dans la bale de Tokyo, au Japon. Cette nouvelle espéce se distingue facilement de tous ses congénères par les caractères uniques suivants chez la femelle : (1) les lobes latéraux, du céphalothorax et les plaques latérales du segment portant la deuxième paire de pattes sont dépourvues de membranes latérales, (2) les plaques dorsales du segment portant la quatrième paire de pattes sont à bord lisse, (3) les lobes postéro- latéraux du complexe génital sont largement écartés à leur base interne et se recouvrent ensuite sur la ligne médiane, (4) les pattes 2 et 3 ont des endopodites tri-segmentés, et (5) la patte 4 possède un exopodite incompletèment bi-segmenté. INTRODUCTION After my redescription of the eight known pandarid copepod species infesting Japanese elasmobrachs was published (Izawa, 2010), I had the opportunity to 1) e-mail: [email protected] © Koninklijke Brill NV, Leiden, 2012 Crustaceana 85 (1): 81-87 Also available online: www.brill.nl/cr DOI:10.1163/156854012X623674 82 KUNIHIKO IZAWA examine a parasitic copepod recovered from the body surface of the goblin shark, Mitsukurina owstoni Jordan, 1898. The shark was captured in the autumn of 2010 on the slopes of the Tokyo Canyon at about 400 m depth in Tokyo Bay, Japan, and is deposited in the Mie Prefectural Museum (MPM), Tsu. Based on this specimen, Echthrogaleus mitsukurinae sp. nov. is described herein. Until now, no parasitic copepod has been reported from the goblin shark, as far as I am aware. Echthrogaleus Steenstrup & Lütken, 1861 currently includes five valid species: E. coleoptratus (Guérin-Méneville, 1837) and E. denticulatus Smith, 1874, both infesting a wide variety of pelagic sharks around the world (Cressey, 1967); E. disciarai Benz & Deets, 1987 recovered from the smoothtail mobula, Mobula thurstoni (Lloyd, 1908) [= M. lucasana Beebe & Tee-Van, 1938] (Myliobatidae) in the Sea of Cortez (Benz & Dees, 1987); E. pellucidus Shiino, 1963 from an unidentified thresher shark (Alopiidae) in Ecuador (Shiino, 1963) and the great white shark, Carcharodon carcharias (Linnaeus, 1758) (Lamnidae) in Hokkaido, Japan (Ho & Kim, 1996, as E. denticulatus); and E. torpedinis Wilson, 1907 from the electric ray, Torpedo nobiliana Bonaparte, 1835 [= T. occidentalis Storer, 1843] (Torpedinidae) at Woods Hole and Provincetown, Massachusetts, U. S. A. (Wilson, 1907). Other than these species, E. indistinctus (Krøyer, 1863), E. neozealanicus (G. M. Thomson, 1890), and E. pectinatus Kirtisinghe, 1964 have been enumerated as valid species on the website of the World of Copepods (Walter & Boxshall, 2011). However, neither of these species can be treated as valid species of the genus. E. neozealanicus has been relegated to a synonym of E. denticulatus by Cressey (1967). From the fact that Krøyer’s description is not very informative and is not accompanied by illustrations, E. indistinctus has been treated as a species inquirenda by Kabata (1979). Kirtisinghe’s (1964) E. pectinatus has many features unusual for the genus and should be investigated in greater detail before its final acceptance in Echthrogaleus as mentioned by Kabata (1979). MATERIAL AND METHODS The specimen was fixed and preserved in ethanol. It was stained with chlorazol black E in lactic acid and examined with a differential interference contrast microscope. Drawings were made with the aid of a drawing tube. Copepod terminology is based on Kabata (1979) and Huys & Boxshall (1991). The common and scientific names of the host conform to Froese & Pauly (2011). Echthrogaleus mitsukurinae sp. nov. (figs. 1-2) Material examined. — A female (holotype) from the body surface adjacent to the gill slits of a female Mitsukurina owstoni Jordan, 1898, 119 cm TL (Lamniformes, Mitsukurinidae), captured by.
Load more

Recommended publications
  • Mitsukurina Owstoni Jordan (Chondrichthyes: Mitsukurinidae) Primer Registro Para El Caribe Colombiano
    Bol . Invest . Mar . Cost . 38 (1) 211-215 ISSN 0122-9761 Santa Marta, Colombia, 2009 NOTA: MITSUKURINA OWSTONI JORDAN (CHONDRICHTHYES: MITSUKURINIDAE) PRIMER REGISTRO PARA EL CARIBE COLOMBIANO Marcela Grijalba-Bendeck y Kelly Acevedo Universidad de Bogotá Jorge Tadeo Lozano, Facultad de Ciencias Naturales, Programa de Biología Marina, Sede Santa Marta, Colombia. [email protected] (M.G.B.), [email protected] (K. A.) ABSTRACT Mitsukurina owstoni Jordan (Chondrichthyes: Mitsukurinidae) first record for the Colombian Caribbean . This paper collects bibliographic information about the Goblin shark, Mitsukurina owstoni (Chondrichthyes: Mitsukurinidae), an uncommon shark from deeper waters . One specimen of this species was captured near Nenguange bay and it is recorded for first time in the Colombian Caribbbean. KEY WORDS: Mitsukurinidae, Mitsukurina owstoni, Goblin shark, Caribbean, Colombia . La pesca artesanal es una herramienta valiosa que ocasionalmente brinda aportes fundamentales al conocimiento en cuanto a biodiversidad de las especies existentes para un lugar, con el hallazgo de ejemplares no registrados a nivel científico, los nuevos aportes son un llamado a la necesidad de monitorear la pesca artesanal de forma constante, con especial atención a los recursos que no representan valor comercial y pueden dar información de lugares no muestreados por otras fuentes . Siendo un ejemplo de ello el tiburón duende, que es una especie oceánica de aguas profundas, con escasas y dispersas capturas a nivel mundial, esta especie de la cual se sabe muy poco de su biología, no había sido registrada antes para el Caribe colombiano, siendo un ejemplar raro incluso para los pescadores artesanales de la zona . Por lo anterior, el objetivo de esta nota es registrar la presencia de M.
    [Show full text]
  • Luís M.D. Barcelos1, 2*, José M.N. Azevedo1, 3, Jürgen Pollerspöck4, and João P
    ACTA ICHTHYOLOGICA ET PISCATORIA (2018) 48 (2): 189–194 DOI: 10.3750/AIEP/02436 REVIEW OF THE RECORDS OF THE SMALLTOOTH SAND TIGER SHARK, ODONTASPIS FEROX (ELASMOBRANCHII: LAMNIFORMES: ODONTASPIDIDAE), IN THE AZORES Luís M.D. Barcelos1, 2*, José M.N. Azevedo1, 3, Jürgen Pollerspöck4, and João P. Barreiros1, 2 1Centre for Ecology, Evolution, and Environmental Changes, Azorean Biodiversity Group, Angra do Heroísmo, Portugal 2Faculty of Agricultural and Environmental Sciences, University of the Azores, Angra do Heroísmo, Portugal 3Faculty of Sciences and Technology, University of the Azores, Ponta Delgada, Portugal 4Bavarian State Collection of Zoology, Munich, Germany Barcelos L.M.D., Azevedo J.M.N., Pollerspöck J., Barreiros J.P. 2018. Review of the records of the smalltooth sand tiger shark, Odontaspis ferox (Elasmobranchii: Lamniformes: Odontaspididae), in the Azores. Acta Ichthyol. Piscat. 48 (2): 189–194. Abstract. In recent years Azorean fishermen reported the presence of the smalltooth sand tiger shark,Odontaspis ferox (Risso, 1810), a very rare demersal shark species, associated with insular shelves and slopes, with occasional incursions into shallow waters and of poorly known biology and ecology. There are fourteen new records of this species, between 1996 and 2014, captured by spearfishing, harpoons, hand lines, or entangled in fishing gear in the Azores. These records were analysed and complemented with fishermen interviews, providing new locations and new biological data for this species. Also, specimens photographs were studied and post-mortem analysis were carefully carried out in one individual. This species is rare and captured only as bycatch in shallow waters. More detailed information on this species is critically needed in order to assess its conservation status and implement management guidelines.
    [Show full text]
  • The Denticle Surface of Thresher Shark Tails: Three-Dimensional Structure and Comparison to Other Pelagic Species
    Received: 3 April 2020 Revised: 14 May 2020 Accepted: 21 May 2020 DOI: 10.1002/jmor.21222 RESEARCH ARTICLE The denticle surface of thresher shark tails: Three-dimensional structure and comparison to other pelagic species Meagan Popp1 | Connor F. White1 | Diego Bernal2 | Dylan K. Wainwright1 | George V. Lauder1 1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Abstract Massachusetts Shark skin denticles (scales) are diverse in morphology both among species and 2 Department of Biology, University of across the body of single individuals, although the function of this diversity is poorly Massachusetts Dartmouth, Dartmouth, Massachusetts understood. The extremely elongate and highly flexible tail of thresher sharks pro- vides an opportunity to characterize gradients in denticle surface characteristics Correspondence George V. Lauder, Museum of Comparative along the length of the tail and assess correlations between denticle morphology and Zoology, 26 Oxford Street, Cambridge, MA tail kinematics. We measured denticle morphology on the caudal fin of three mature 02138. Email: [email protected] and two embryo common thresher sharks (Alopias vulpinus), and we compared thresher tail denticles to those of eleven other shark species. Using surface Funding information National Oceanic and Atmospheric profilometry, we quantified 3D-denticle patterning and texture along the tail of Administration, Grant/Award Number: threshers (27 regions in adults, and 16 regions in embryos). We report that tails of NA16NMF4270231; National Science Foundation, Grant/Award Numbers: IOS- thresher embryos have a membrane that covers the denticles and reduces surface 1354593, GRF DGE-1144152; Office of Naval roughness. In mature thresher tails, surfaces have an average roughness of 5.6 μm Research, Grant/Award Numbers: N00014-09-1-0352, N000141410533 which is smoother than some other pelagic shark species, but similar in roughness to blacktip, porbeagle, and bonnethead shark tails.
    [Show full text]
  • Population Structure and Biology of Shortfin Mako, Isurus Oxyrinchus, in the South-West Indian Ocean
    CSIRO PUBLISHING Marine and Freshwater Research http://dx.doi.org/10.1071/MF13341 Population structure and biology of shortfin mako, Isurus oxyrinchus, in the south-west Indian Ocean J. C. GroeneveldA,E, G. Cliff B, S. F. J. DudleyC, A. J. FoulisA, J. SantosD and S. P. WintnerB AOceanographic Research Institute, PO Box 10712, Marine Parade 4056, Durban, South Africa. BKwaZulu-Natal Sharks Board, Private Bag 2, Umhlanga Rocks 4320, South Africa. CFisheries Management, Department of Agriculture, Forestry and Fisheries, Private Bag X2, Rogge Bay 8012, South Africa. DNorwegian College of Fishery Science, University of Tromsø, NO-9037, Tromsø, Norway. ECorresponding author. Email: [email protected] Abstract. The population structure, reproductive biology, age and growth, and diet of shortfin makos caught by pelagic longliners (2005–10) and bather protection nets (1978–2010) in the south-west Indian Ocean were investigated. The mean fork length (FL) of makos measured by observers on longliners targeting tuna, swordfish and sharks was similar, and decreased from east to west, with the smallest individuals occurring near the Agulhas Bank edge, June to November. Nearly all makos caught by longliners were immature, with equal sex ratio. Makos caught by bather protection nets were significantly larger, males were more frequent, and 93% of males and 55% of females were mature. Age was assessed from band counts of sectioned vertebrae, and a von Bertalanffy growth model fitted to sex-pooled length-at-age data predicted a À1 birth size (L0) of 90 cm, maximum FL (LN) of 285 cm and growth coefficient (k) of 0.113 y .
    [Show full text]
  • Identification Guide to the Deep-Sea Cartilaginous Fishes Of
    Identification guide to the deep–sea cartilaginous fishes of the Southeastern Atlantic Ocean FAO. 2015. Identification guide to the deep–sea cartilaginous fishes of the Southeastern Atlantic Ocean. FishFinder Programme, by Ebert, D.A. and Mostarda, E., Rome, Italy. Supervision: Merete Tandstad, Jessica Sanders (FAO, Rome) Technical editor: Edoardo Mostarda (FAO, Rome) Colour illustrations, cover and graphic design: Emanuela D’Antoni (FAO, Rome) This guide was prepared under the “FAO Deep–sea Fisheries Programme” thanks to a generous funding from the Government of Norway (Support to the implementation of the International Guidelines on the Management of Deep-Sea Fisheries in the High Seas project) for the purpose of assisting states, institutions, the fishing industry and RFMO/As in the implementation of FAO International Guidelines for the Management of Deep-sea Fisheries in the High Seas. It was developed in close collaboration with the FishFinder Programme of the Marine and Inland Fisheries Branch, Fisheries Department, Food and Agriculture Organization of the United Nations (FAO). The present guide covers the deep–sea Southeastern Atlantic Ocean and that portion of Southwestern Indian Ocean from 18°42’E to 30°00’E (FAO Fishing Area 47). It includes a selection of cartilaginous fish species of major, moderate and minor importance to fisheries as well as those of doubtful or potential use to fisheries. It also covers those little known species that may be of research, educational, and ecological importance. In this region, the deep–sea chondrichthyan fauna is currently represented by 50 shark, 20 batoid and 8 chimaera species. This guide includes full species accounts for 37 shark, 9 batoid and 4 chimaera species selected as being the more difficult to identify and/or commonly caught.
    [Show full text]
  • Record of the Goblin Shark Mitsukurina Owstoni (Chondrichthyes
    Marine Biodiversity Records, page 1 of 5. # Marine Biological Association of the United Kingdom, 2012 doi:10.1017/S1755267211000923; Vol. 5; e44; 2012 Published online Record of the goblin shark Mitsukurina owstoni (Chondrichthyes: Lamniformes: Mitsukurinidae) from the south-western Atlantic getulio rincon1, teodoro vaske ju’ nior2 and otto b.f. gadig2 1Conepe-Conselho Nacional de Pesca e Aquicultura, Setor Hoteleiro Sul, Quadra 6, Conj. A, Bloco E, Edifı´cio Brasil 21, Salas 10-13, CEP 70322-915, Brası´lia, Distrito Federal, Brazil, 2UNESP, Campus Experimental do Litoral Paulista, Prac¸a Infante Dom Henrique s/n, CEP 11330-900, Sa˜o Vicente, Sa˜o Paulo, Brazil This paper reports the first well-documented specimen of the goblin shark, Mitsukurina owstoni in the south-western Atlantic, based on a mature male measuring 3152 mm total length, caught on 27 November 2008 off the Rio de Janeiro coast, south- east Brazil. Keywords: goblin shark, Mitsukurina owstoni, occurrence, south-western Atlantic Submitted 26 June 2011; accepted 25 July 2011 INTRODUCTION Colombia (Grijalba-Bendeck & Acevedo, 2009), French Guiana (Uyeno & Sasaki, 1983) and northern Brazil The goblin shark, Mitsukurina owstoni (Jordan, 1898) is the (Holanda & Asano-Filho, 2008). single representative of the family Mitsukurinidae, order Although widely distributed, some available biological and Lamniformes (mackerel sharks), distributed worldwide in distribution data are controversial. For example, the first deep waters down to at least 1300 m and occasionally reaching record from the western North Atlantic, in fact was not that the shallow upper slopes of submarine canyons. It is one of the published by Uyeno et al. (1983), but from Kukuev (1982) most bizarre large sharks known, attaining about 4100 mm who reported nine specimens collected between 1976 and total length, and characterized by its long and well depressed 1978 at Corner Mountains and New England Seamounts.
    [Show full text]
  • Body Length Estimation of Neogene Macrophagous Lamniform Sharks (Carcharodon and Otodus) Derived from Associated Fossil Dentitions
    Palaeontologia Electronica palaeo-electronica.org Body length estimation of Neogene macrophagous lamniform sharks (Carcharodon and Otodus) derived from associated fossil dentitions Victor J. Perez, Ronny M. Leder, and Teddy Badaut ABSTRACT The megatooth shark, Otodus megalodon, is widely accepted as the largest mac- rophagous shark that ever lived; and yet, despite over a century of research, its size is still debated. The great white shark, Carcharodon carcharias, is regarded as the best living ecological analog to the extinct megatooth shark and has been the basis for all body length estimates to date. The most widely accepted and applied method for esti- mating body size of O. megalodon was based upon a linear relationship between tooth crown height and total body length in C. carcharias. However, when applying this method to an associated dentition of O. megalodon (UF-VP-311000), the estimates for this single individual ranged from 11.4 to 41.1 m. These widely variable estimates showed a distinct pattern, in which anterior teeth resulted in lower estimates than pos- terior teeth. Consequently, previous paleoecological analyses based on body size esti- mates of O. megalodon may be subject to misinterpretation. Herein, we describe a novel method based on the summed crown width of associated fossil dentitions, which mitigates the variability associated with different tooth positions. The method assumes direct proportionality between the ratio of summed crown width to body length in eco- logically and taxonomically related fossil and modern species. Total body lengths were estimated from 11 individuals, representing five lamniform species: Otodus megal- odon, Otodus chubutensis, Carcharodon carcharias, Carcharodon hubbelli, and Carcharodon hastalis.
    [Show full text]
  • Acoustic Tracking of Bigeye Thresher Shark Alopias Superciliosus in the Eastern Pacific Ocean
    MARINE ECOLOGY PROGRESS SERIES Vol. 265: 255–261, 2003 Published December 31 Mar Ecol Prog Ser Acoustic tracking of bigeye thresher shark Alopias superciliosus in the eastern Pacific Ocean Hideki Nakano*, Hiroaki Matsunaga, Hiroaki Okamoto, Makoto Okazaki National Research Institute of Far Seas Fisheries, 5-7-1 Shimizu-Orido, Shizuoka 424-8633, Japan ABSTRACT: Acoustic telemetry was used to identify the short-term horizontal and vertical movement patterns of the bigeye thresher shark Alopias superciliosus in the eastern tropical Pacific Ocean dur- ing the summer of 1996. Two immature female sharks, 175 and 124 cm PCL (precaudal length), were tracked for 96 and 70 h, respectively, demonstrating very distinct crepuscular vertical migrations sim- ilar to those reported for the megamouth shark. The bigeye threshers stayed at 200 to 500 m depth during the day and at 80 to 130 m at night. The deepest dive extends the known depth distribution of the species to 723 m. No ‘fly-glide’ behavior (rapid ascents followed by slower acute-angled descents) was observed for the 2 sharks. However, the opposite behavioral pattern of slow ascents and rela- tively rapid descents during the night was observed. Since bigeye threshers have large eyes extend- ing upwards onto the dorsal surface of the cranium, it may be more efficient for them to hunt prey which are highlighted against the sea surface from below. Estimated mean swimming speed over the ground ranged from 1.32 to 2.02 km h–1, similar to swordfish and megamouth sharks, and slower than that reported for tunas, billfishes, and other pelagic sharks.
    [Show full text]
  • Migration and Habitat Utilization in Lamnid Sharks
    MIGRATION AND HABITAT UTILIZATION IN LAMNID SHARKS A DISSERTATION SUBMITTED TO THE DEPARTMENT OF BIOLOGICAL SCIENCES AND THE COMMITTEE ON GRADUATE STUDIES OF STANFORD UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Kevin Chi-Ming Weng May 2007 © Copyright by Kevin Chi-Ming Weng 2007 All Rights Reserved ii Abstract Understanding the movements, habitat utilization, and life history of high trophic level animals is essential to understanding how ecosystems function. Furthermore, large pelagic vertebrates, including sharks, are declining globally, yet the movements and habitats of most species are unknown. A variety of satellite telemetry techniques are used to elucidate the movements and habitat utilization of two species of lamnid shark. Salmon sharks used a subarctic to subtropical niche, and undertook long distance seasonal migrations between subarctic and subtropical regions of the eastern North Pacific, exhibiting the greatest focal area behavior in the rich neritic waters off Alaska and California, and showing more transitory behaviors in pelagic waters where productivity is lower. The timing of salmon shark aggregations in both Alaska and California waters appears to correspond with life history events of an important group of prey species, Pacific salmon. The enhanced expression of excitation-contraction coupling proteins in salmon shark hearts likely underlies its ability to maintain heart function at cold temperatures and their niche expansion into subarctic seas. Adult white sharks undertake long distance seasonal migrations from the coast of California to an offshore focal area 2500 km west of the Baja Peninsula, as well as Hawaii. A full migration cycle from the coast to the offshore focal area and back was documented.
    [Show full text]
  • Caudal Fin Skeleton of the Late Cretaceous Lamniform Shark, Cretoxyrhina Mantelli, from the Niobrara Chalk of Kansas
    Lucas, S. G. and Sullivan, R.M., eds., 2006, Late Cretaceous vertebrates from the Western Interior. New Mexico Museum of Natural History and Science Bulletin 35. 185 CAUDAL FIN SKELETON OF THE LATE CRETACEOUS LAMNIFORM SHARK, CRETOXYRHINA MANTELLI, FROM THE NIOBRARA CHALK OF KANSAS KENSHU SHIMADA1, STEPHEN L. CUMBAA2, AND DEANNE VAN ROOYEN3 1Environmental Science Program and Department of Biological Sciences, DePaul University, 2325 North Clifton Avenue, Chicago, Illinois 60614; and Sternberg Museum of Natural History, Fort Hays State University, 3000 Sternberg Drive, Hays, Kansas 67601; 2Paleobiology, Canadian Museum of Nature, P.O. Box 3443, Station D, Ottawa, Ontario K1P 6P4, Canada; 3Department of Earth Sciences, Carleton University, 2240 Herzberg Laboratories, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada. Abstract—The caudal fin morphology of the Late Cretaceous lamniform shark, Cretoxyrhina mantelli (Agassiz), was previously inferred from scale morphology, which suggested that it was capable of fast swimming. A specimen from the Niobrara Chalk of western Kansas is described here and offers new insights into the morphology of the caudal fin of the taxon. The specimen preserves the posterior half of the vertebral column and a series of hypochordal rays. These skeletal elements exhibit features suggesting that C. mantelli had a lunate tail and a caudal peduncle with a lateral fluke. The specimen also supports the idea that the body form of C. mantelli resembled that of the extant white shark, Carcharodon carcharias (Linneaus). Given a total vertebral count in Cretoxyrhina mantelli of about 230, this specimen suggests that the transition between precaudal and caudal vertebrae was somewhere between the 140th and 160th vertebrae.
    [Show full text]
  • Two New Species of Litobothrium Dailey, 1969 (Cestoda
    Systematic Parasitology 48: 159–177, 2001. 159 © 2001 Kluwer Academic Publishers. Printed in the Netherlands. Two new species of Litobothrium Dailey, 1969 (Cestoda: Litobothriidea) from thresher sharks in the Gulf of California, Mexico, with redescriptions of two species in the genus P. D. Olson1;2 &J.N.Caira2 1Parasitic Worms Division, Department of Zoology, The Natural History Museum,Cromwell Road, London SW7 5BD, UK 2Department of Ecology & Evolutionary Biology, University of Connecticut, Storrs, CT 06269-3043, USA Accepted for publication 5th June, 2000 Abstract As part of a survey of the metazoan parasites of elasmobranchs of the Gulf of California, Mexico, the spiral intestines of 10 pelagic thresher sharks Alopias pelagicus and one bigeye thresher shark A. superciliosus were examined for tapeworms. Eight of the A. pelagicus specimens examined were found to host Litobothrium amplifica and L. daileyi. Both tapeworm species are redescribed based on examination of this new material with light and scanning electron microscopy, and the ranges of most of the measurements for these species are expanded; scanning electron micrographs and detailed illustrations and measurements of their segment anatomy are presented for the first time. An argument is made that the identification of the original host specimens of these species was in error and that A. pelagicus is likely to be the correct original host. In addition, L. nickoli n. sp., a third species in the genus hosted by A. pelagicus, was found in three of the 10 individual hosts examined. This species differs from all six known Litobothrium species in the form of the pseudosegments of the scolex, the anterior two being essentially non-cruciform, while the latter three are distinctly cruciform.
    [Show full text]
  • Mitsukurina Owstoni
    Published Date: 1 March 2019 Goblin Shark, Mitsukurina owstoni Report Card Sustainable assessment IUCN Red List IUCN Red List Australian Least Concern Global Least Concern Assessment Assessment Assessors Ebert, D.A., Duffy, C.A.J., Buscher, E. & Stehmann, M.F.W. Report Card Remarks In Australia, only a few specimens have been recorded Summary The Goblin Shark is an apparently rare deepwater shark. It has a widespread but patchy distribution in the Pacific, Indian and Atlantic Oceans. In Australia, only a few specimens have been caught as an occasional bycatch in the South Eastern Scalefish and Shark Fishery trawl sector. It may be occupying areas beyond the depths trawled or in areas not yet fished. Elsewhere it is only infrequently taken in deepwater fisheries. It is likely to be found in more Source: Julian Finn/Museum Victoria. License: locations than previously known when deepwater CC BY Attribution surveys are undertaken in other regions or as deepwater fisheries expand globally. Therefore, the species is currently assessed as globally, and in Australia, as Least Concern (IUCN) and in Australia as Sustainable (SAFS). Distribution The Goblin Shark species has a wide but patchy distribution across the Atlantic, Pacific and West Indian Oceans. In Australia, a few specimens have been recorded off New South Wales, eastern Bass Strait, Tasmania and possibly South Australia (Stevens and Paxton 1985, Last and Stevens 2009). The species is likely to occur in more locations than presently known. Stock structure and status There is currently no information on population size, structure, or trend for the species in Australia, where it is naturally rare or occupies areas outside the fished area.
    [Show full text]