Abstract
Two deep-sea polyclad species are described. Both species were found in association with wood-boring bivalves on oak and fir wood blocks that had been deployed on heavy sediment in the Cascadia Basin and Escanaba Trough in the North Pacific Ocean. Anocellidus profundus n. gen. n. sp. warrants erection of Anocellidae, n. fam. because of the unique position and orientation of the male copulatory apparatus. A. profundus lacks eyes but has long, nuchal tentacles and a ventral, arrowhead-shaped organ of putative sensory function. The male copulatory apparatus is located posterior to the male gonopore and is directed anteriorly. Highly muscularized spermiducal bulbs are present, a prostatic vesicle is lacking. A large Lang’s vesicle characterizes the female reproductive system. Oligocladus voightae n. sp. is defined by the presence of a mouth located anterior to the brain. Few and minute tentacular eyes are present. The seminal vesicle is connected to an auxiliary sperm storage vesicle, and a posterior anal pore is present in the main median branch of the intestine. All type material is deposited at the Field Museum of Natural History, Chicago, Illinois, USA.
References
Bock, S. (1913) Studien über Polycladen. Zoologiska Bidrag fran Uppsala 2, 29–344.
Bolaños, D.M., Quiroga, S.Y. & Litvaitis, M.K. (2006) A new acotylean flatworm, Armatoplana colombiana n. sp. (Platyhelminthes: Polycladida: Stylochoplanidae) from the Caribbean coast of Colombia, South America. Zootaxa, 1162, 53–64.
Brunner, C.A., Normak, W.R., Zuffa, G.G. & Serra, F. (1999) Deep-sea sedimentary record of the late Wisconsin cataclysmic floods from the Colombia River. Geology, 27(5), 463–466.
Chintala, M.M. & Kennedy, V.S. (1993) Reproduction of Stylochus ellipticus (Platyhelminthes: Polycladida) in response to temperature, food, and presence or absence of a partner. Biological Bulletin, 185, 373–387.
Christensen, D.J. (1973) Prey preference of Stylochus ellipticus in Chesapeake Bay. Proceedings of the National Shellfish Association, 63, 35–38.
Faubel, A. (1983) The Polycladida, Turbellaria. Proposal and establishment of a new system. Part I. The Acotylea. Mitteilungen des hamburgischen zoologischen Museums und Instituts, 80, 17–121.
Faubel, A. (1984a) The Polycladida, Turbellaria. Proposal and establishment of a new system. Part II. The Cotylea. Mitteilungen des hamburgischen zoologischen Museums und Instituts, 81, 189–259.
Faubel, A. (1984b) On the geographical occurrence of pelagic polyclad turbellarians. Cahiers de Biologie Marine, 25, 153–168.
Galleni, L., Tongiorgi, P., Ferroro, E. & Salghetti, U. (1980) Stylochus mediterraneus (Turbellaria: Polycladida), predator on the mussel Mytilus galloprovincialis. Marine Biology 55, 317–326.
Hadenfeldt, D. (1929) Das Nervensystem von Stylochoplana maculata und Notoplana atomata. Zeitschrift für wissenschaftliche Zoology, 133, 586–638.
Herring, P. (2002) The Biology of the Deep Ocean. Biology of Habitats. Oxford University Press, 314 pp.
Hyman L.H. (1951) The Invertebrates: Vol. II. Platyhelminthes and Rhynchocoela; the acelomate Bilateria. McGraw-Hill, New York, 572pp
Lang, A. (1884) Die Polycladen (Seeplanarien) des Golfes von Neapel und der angrenzenden Meeresabschnitte. Eine Monographie. Fauna und Flora des Golfes von Neapel 11. ix + 688 pp. Leipzig.
Marcus, E. (1952) Turbellaria Brasileiros (10) Boletin da facultade de filosofia ciencias y letras de Sao Paulo Zoologia No 17, 5–188.
Marcus, E. (1954) Reports of the Lund University Chile Expedition 1948–49. 11. Turbellaria. Lunds Universitets Arsskrift. N. F. 49 (13), 1–115.
Murina, G.-V., Grintsov, V. & Solonchenko, A. (1995) Stylochus tauricus, a predator of the barnacle Balanus improvisus in the Black Sea. Hydrobiologia 305, 101–104.
Newell, R.I.E., Alspach, G.S., Kennedy, V.S. & Jacobs, D. (2000) Mortality of newly metamorphosed eastern oysters (Crassostrea virginica) in mesohaline Chesapeake Bay. Marine Biology, 136, 665–676.
Newman, L.J., Cannon, L.R.G. & Govan, H. (1993) Stylochus (Imogene) matatasi n. sp. (Platyhelminthes, Polycladida): Pest of cultured giant clams and pearl oysters from Solomon Islands. Hydrobiologia, 257, 185–189.
O'Connor, W.A. & Newman, L.J. (2001) Halotolerance of the oyster predator, Imogine mcgrathi, a stylochid flatworm from Port Stephens, New South Wales, Australia. Hydrobiologia 459, 157–163.
Palombi, A. (1924) Policladi pelagici. Raccolte planktoniche fatte dalla R. N. “Liguria” nel viaggio di circonnavigazione del 1903–05. Pubblicazioni Recerchi del Istituto degli Studi Superiori Firenze 3, 1–28.
Provenzano, A.J. (1961) Effects of the flatworm Stylochus ellipticus (Girard) on oyster spat in two salt water ponds in Massachusetts. Proceedings of the National Shellfish Association 50, 83–88.
Prudhoe, S. (1985) A Monograph on Polyclad Turbellaria. Oxford University Press: Oxford.
Ritson-Williams, R., Yotsu-Yamashita, M. & Paul, V.J. (2006) Ecological functions of tetrodotoxin in a deadly polyclad flatworm. Proceedings of the National Academy of Sciences 103, 3176–3179.
Turner, R.D. (1978) Wood, mollusks, and deep-sea food chains. Bulletin of the American Malacological Union for 1977, 13–19.
Villalba, A., Mourelle, S.G., Carballal, M.J. & Lopez, C. (1997) Symbionts and diseases of farmed mussels Mytilus galloprovincialis throughout the culture process in the Rias of Galicia (NW Spain). Diseases of Aquatic Organisms 31, 127–139.
Voight, J.R. (2005) First report of the enigmatic echinoderm Xyloplax from the North Pacific. Biological Bulletin 208, 77–80.
Webster, J.R. & Medford, R.Z. (1961) Flatworm distribution and associated oyster mortality in Chesapeake Bay. Proceedings of the National Shellfish Association 50, 89–96.