Evaluating The Anesthetization And Fixation Efficacy Of “soft” And “hard” Freshwater Benthic Meiofauna: What Is The Best Method For Specimen Preservation?

Sampling freshwater biological diversity is a challenge when it comes down to techniques for meiofauna fixation and preservation because this polyphyletic group of taxa is highly diverse. The aim of this study is to test the performance of three anesthetics (CO2, MgCl2 and low temperature) and three fixatives (formaldehyde 4 %; buffered formaldehyde 4 and 70 % ethanol) in the preservation of “soft” (gastrotrichs and rotifers) and “hard” (tardigrades and copepods) freshwater benthic meiofaunal assemblages. Due to these different morphological structures, we expected that treatment performance would vary among taxa in the quality of specimen fixation. Results revealed that the meiofaunal abundances of samples sorted alive or after the treatments with a coupling of anesthetics and fixatives were not different. However, preservation of specimens varied substantially among “soft” and “hard” meiofauna and among treatments. The use of 4 % buffered formaldehyde is highly recommended for freshwater meiofauna, while unbuffered formaldehyde should be avoided. Studies that have “soft” meiofauna as target organisms are recommended to use some type of anesthetic, although it is necessary to use a specific one for each taxon as they respond in different ways to different anesthetics. © 2016, The Japanese Society of Limnology.18220921

The Gametogenic Cycle And Life History Of Nicolea Uspiana (polychaeta: Terebellidae) On The South-east Coast Of Brazil

The gametogenic cycle and life history of Nicolea uspiana (Nogueira, 2003) (Polychaeta: Terebellidae) was studied by taking monthly samples over a 13 month period. Each month, 10 females were sorted; 50 oocytes were removed from the coelom of each specimen, and the maximum diameter was determined. Additionally, 10 males were sorted and 100 gametes were randomly selected from each specimen to evaluate their shape and maturation stage. This species is gonochoric and exhibits slight external sexual dimorphism (in the shape of the nephridial papillae). The sex-ratio of N. uspiana was 2.4 male for each female. The initial gametic stages of both sexes are produced in special structures called nephromixia. Oogenesis is extra-ovarian, and the germ cells are clumped and surrounded by follicle cells. These cells are ovulated into the coelomic fluid, and yolk synthesis occurs in this cavity. The maximum diameter of oocytes measured, 225 m, showed that these eggs fall into the size-range for lecithotrophy. Furthermore, N. uspiana is an iteroparous species, as the mature individuals can breed several times during their lifetime. Male gonads release germ cells early in development, and sperm maturation also occurs in the coelomic fluid. The male gametes consist of flattened plaques of germ cells attached on their anterior part by a cytophore assuming a rosette-like appearance. Following maturation of the male cells, the spermatids produce arrays of stiffly vibratile tails, assuming a morula shape. The reproductive patterns and life history of the terebellids are also discussed. Copyright © Marine Biological Association of the United Kingdom 2014.945925933Allen, J.D., Pernet, B., Intermediate modes of larval development: Bridging the gap between planktotrophy and lecithotrophy (2007) Evolution & Development, 9, pp. 643-653Benham, W.B., External sexual differences in the terebellid worms (1927) Proceedings of Zoological Society of London, 1, pp. 141-148Bhaud, M., Change in setal pattern during early development of Eupolymnia nebolusa (Polychaeta: Terebellidae) grown in simulated natural conditions (1988) Journal of the Marine Biological Assossiation of United Kingdom, 68, pp. 677-687Bhaud, M., The two planktonic larval periods of Lanice conchilega (Pallas, 1766) Annelida Polychaeta, a peculiar example of the irreversibility of evolution (1988) Ophelia, 29, pp. 141-152Bhaud, M., Larval release from the egg mass and settlement of Eupolymniu nebulosa (Polychaeta, Terebellidae) (1991) Bulletin of Marine Science, 48, pp. 420-431Bhaud, M., Grémare, A., Larval development of the terebellid polychaete Eupolymnia nebulosa (Montagu) in the Mediterranean Sea (1988) Zoologica Scripta, 17, pp. 347-356Blake, J.A., Larval development of Polychaeta from the Northern California coast V. Ramex californiensis Hartman (Polychaeta: Terebellidae) (1991) Bulletin of Marine Science, 48, pp. 448-460Blake, E.A., Van Dover, C.L., The reproductive biology of Amathys lutzi, an ampharetid polychaete from hydrothermal vents on the Mid-Atlantic Ridge (2005) Invertebrate Biology, 124, pp. 254-264Blankensteyn, A., Moreno, T.R., Nova ocorrência de Nicolea venustula (Montagu) (Polychaeta, Terebellidae) na costa sul do Brasil (1999) Revista Brasileira de Zoologia, 16, pp. 319-320Christie, G., Observations on the reproductive biology of Trichobranchus glacialis Malmgren, 1866 (Polychaeta: Trichobranchidae) (1986) Sarsia, 71, pp. 259-263Duchêne, J.C., Premiéres donnèes sur la reproduction et la croissance de la polychète Thelepus setosus (Terebellidae) en province subantarctique (1979) Annales de l'Institut Océanographique, 55, pp. 145-154Duchêne, J.C., Premiéres donnèes sur la reproduction at la croissance de la polychète Neoleprea streptochaeta (Terebellidae) em province subantarctique (1980) Annales de l'Institut Océanographique, 56, pp. 109-115Duchêne, J.C., Growth rate, fecundity and spawning in two subantarctic populations of Thelepus setosus (Quatrefages) (Polychaeta: Terebellidae) (1991) Ophelia, 5, pp. 313-320Eckelharger, K.J., Population biology and larval development of the terebellid polychaete Nicoleu zostericola (1974) Marine Biology, 27, pp. 101-113Eckelharger, K.J., A light and electron microscope investigation of gametogenesis in Nicolea zostericola (Polychaeta: Terebellidae) (1975) Marine Biology, 30, pp. 353-370Eckelbarger, K.J., Origin and development of the amoebocytes of Nicolea zostericola (Polychaeta: Terebellidae) with a discussion of their possible role in oogenesis (1976) Marine Biology, 36, pp. 169-182Fauchald, K., Life diagram patterns in benthic polychaetes (1983) Proceedings of the Biological Society of Washington, 96, pp. 160-177Franzén, A., On spermiogenesis, morphology of the spermatozoon and biology of fertilization among invertebrates (1956) Zoologiska Bidrag Från Uppsala, 31, pp. 355-482Garraffoni, A.R.S., Amaral, A.C.Z., Postlarval development of Nicolea uspiana (Polychaeta: Terebellidae) (2009) Zoologia, 26, pp. 61-66Garraffoni, A.R.S., Lana, P.C., Phylogenetic relationships within Terebellidae (Polychaeta: Terebelomorpha) based on morphological characters (2008) Invertebrate Systematics, 22, pp. 605-626Garraffoni, A.R.S., Nihei, S.S., Lana, P.C., Distribution patterns of Terebellidae (Annelida: Polychaeta): An application of Parsimony Analysis of Endemicity (PAE) (2006) Scientia Marina, 70 S3, pp. 269-276Garraffoni, A.R.S., Yokoyama, L.Q., Amaral, A.C.Z., Allometry and population structure of Nicolea uspiana (Polychaeta: Terebellidae) (2010) Journal of the Marine Biological Association of the United Kingdom, 90, pp. 877-883Giangrande, A., Polychaeta reproductive patterns, life cycles and life histories: An overview (1997) Oceanography and Marine Biology: An Annual Review, 35, pp. 323-386Giangrande, A.G., Belmonte, G., Geraci, S., Life cycle and life history traits diversity in marine invertebrates and implications in community dynamics (1994) Oceanography and Marine Biology: An Annual Review, 32, pp. 305-333Heimler, W., Untersuchungen zur Larvalentwicklung von Lanice conchilega (Pallas) 1766 (Polychaeta, Terebellomorpha). Teil II: Bau und Ultrastruktur der Trochophora-Larve (1981) Zoologische Jahrbücher Anatomie und Ontogenie der Tiere, 106, pp. 236-277Hutchings, P., Family Trichobranchidae (2000) Polychaeta & Allies: The Southern Synthesis. Fauna of Australia. Volume 4a Polychaeta, Myzostomida, Pogonophora, Echiura, Sipuncula, pp. 232-235. , Beesley P.L., Ross G.L.B. and Glasby C. J. (eds), Melbourne: CSIROHutchings, P.A., Glasby, C.J., The Amphitritinae (Polychaeta: Terebellidae) from Australia (1988) Records of the Australian Museum, 40, pp. 1-60Jamieson, B.G.M., Rouse, G.W., The spermatozoa of the Polychaeta (Annelida): An ultrastructural review (1989) Biological Reviews, 64, pp. 93-157Jeffery, C.H., Emlet, R.B., Macroevolutionary consequences of developmental mode in temnopleurid echinoids from the Tertiary of Southern Australia (2003) Evolution, 57, pp. 1031-1048Marcano, G., Bhaud, M., New observations on the terebellid (Polychaeta) aulophore larvae on the French coast (1995) Ophelia, 43, pp. 229-244Marshall, D.J., Keough, M.J., The evolutionary ecology of offspring size in marine invertebrates (2007) Advances in Marine Biology, 53, pp. 1-60McHugh, D., A comparative study of reproduction and development in the Polychaeta family Terebellidae (1993) Biological Bulletin, 185, pp. 153-167. , Marine Biological Laboratory, Woods HoleMcHugh, D., Phylogenetic analysis of the Amphitritinae (Polychaeta: Terebellidae) (1995) Zoological Journal of the Linnean Society, 114, pp. 405-429McHugh, D., Fong, P.P., Do life history traits account for diversity of polychaete annelids? (2002) Invertebrate Biology, 121, pp. 325-338McHugh, D., Rouse, G.W., Life history evolution of marine invertebrates: New views from phylogenetic systematics (1998) Trends in Ecology and Evolution, 13, pp. 182-186Moran, A.L., McAlister, J.S., Egg size as a life history character of marine invertebrates: Is it all it's cracked up to be? (2009) Biollogical Bulletin, 216, pp. 226-242. , Marine Biological Laboratory, Woods HoleNogueira, J.M.M., A new species of Paraeupolymnia Young and Kritzler, 1986 (Polychaeta, Terebellidae, Terebellinae) from Brazil (2003) Scientia Marina, 67, pp. 407-413Nogueira, J.M.M., Hutchings, P.A., Fukuda, M.V., Morphology of terebelliform polychaetes (Annelida: Polychaeta: Terebelliformia), with a focus on Terebellidae (2010) Zootaxa, 2460, pp. 1-185Nylin, S., Gotthar, K., Plasticity in life-history traits (1998) Annual Revision of Entomology, 43, pp. 63-83Qian, P.Y., Dahms, H.U., Larval ecology of the Annelida (2006) Reproductive Biology and Phylogeny of Annelida, pp. 179-232. , Rouse G.W. and Pleijel F. (eds), Enfield, NH: Science PublishersRamirez-Llodra, E.R., Fecundity and life-history strategies in marine invertebrates (2002) Advances in Marine Biology, 43, pp. 87-170Rouse, G.W., Family terebellidae (2001) Polychaetes, pp. 246-250. , Rouse G.W. and Pleijel F. (eds), Oxford: Oxford University PressRouse, G.W., Annelid sperm and fertilization biology (2005) Hydrobiologia, 535-536, pp. 167-178Rouse, G.W., Fauchald, K., Cladistics and polychaetes (1997) Zoologica Scripta, 26, pp. 269-301Rouse, G.W., Fitzhugh, J.K., Broadcasting fables: Is external fertilization really primitive? Sex, size, and larvae in sabellid polychaetes (1994) Zoologica Scripta, 23, pp. 271-312Rouse, G.W., Jamieson, B.G.M., An ultrastructural study of the spermatozoa of the polychaetes Eurythoe complantata (Amphinomidae), Clymenella sp. and Micromaldane sp. (Maldanidae), with definition of sperm types in relation to reproductive biology (1987) Journal of Submicroscopic Cytology, 19, pp. 573-584Rouse, G.W., McHugh, D., Ultrastructure of spermatids and spermatozoa in Ramex californiensis and Nicolea zostericola (TerebellidaePolycheata) (1994) Ophelia, 39, pp. 225-238Santos, A.S., Nogueira, J.M.M., Fukuda, M.V., Christoffersen, M.L., New terebellids (Polychaeta: Terebellidae) from northeastern Brazil (2010) Zootaxa, 2389, pp. 1-46Schroeder, P.C., Hermans, C.O., Annellida: Polychaeta (1975) Reproduction of Marine Invertebrate, 3, pp. 1-123. , Giese A.C. and Pearse J.R. (eds), New York: Academic PressScott, J.W., Some egg-laying habits of Amphitrite ornata Verrill (1909) Biological Bulletin, 17, pp. 327-340. , Marine Biological Laboratory, Woods HoleScott, J.W., Further experiments on the methods of egg-laying in Amphitrite (1910) Biological Bulletin, 20, pp. 252-265. , Marine Biological Laboratory, Woods HoleSeitz, R.D., Schaffner, L.C., Population ecology and secondary production of the polychaete Loimia medusa (Terebellidae) (1995) Marine Biology, 121, pp. 701-711Smith, R.I., Observations on spawning behavior of Eupolymnia nebulosa, and comparisons with Lanice conchilega (Annelida, Polychaeta, Terebellidae) (1989) Bulletin of Marine Science, 45, pp. 406-414Smith, R.I., Notes on gamete production in Lanice conchilega (Annelida, Polychaeta, Terebellidae) (1989) Invertebrate Reproduction and Development, 15, pp. 7-12Smith, R.I., Three nephromixial patterns in Polychaeta species currently assigned to the genus Pista (Annelida, Terebellidae) (1992) Journal of Morphology, 213, pp. 365-393Smith, R.I., A systematic problem of inter- and intra-generic variation in nephromixia of Terebellidae (1994) Memoires du Muséum Naturelle d'Histoire, 162, pp. 287-289Strathmann, R.R., Feeding and nonfeeding larval development and life-history evolution in marine invertebrates (1985) Annual Reviews in Ecology and Systematics, 16, pp. 339-361Strathmann, R.R., Hypotheses on the origins of marine larvae (1993) Annual Reviews in Ecology and Systematics, 24, pp. 89-117Thorson, G., Reproduction and larval development of Danish marine bottom invertebrates, with special reference to the planktonic larvae in the Sound (Oresund) (1946) Meddelelser Fra Kommissionen for Danmarks Fiskeri- Og Havundersøgelser, Serie: Plankton, 4, pp. 1-523Thorson, G., Reproductive and larval ecology of marine invertebrates (1950) Biological Review, 25, pp. 1-45Wilson, D.P., Post-larval development of Loimia medusa Sav (1928) Journal of the Marine Biological Assossiation of United Kingdom, 15, pp. 129-149Wilson, W.H., Sexual reproductive modes in polychaetes: Classification and diversity (1991) Bulletin of Marine Science, 48, pp. 500-516Wray, G.A., Raff, R.A., Rapid evolution of gastrulation mechanisms in a sea urchin with lecithotrophic larvae (1991) Evolution, 45, pp. 1741-1750Zhadan, A.E., Tzetlin, B., Comparative morphology of the feeding apparatus in the Terebellida (Annelida: Polychaeta) (2002) Cahiers de Biologie Marine, 43, pp. 149-164Von, W.R., Biologische Beobachtungen über niedere Meeresthiere (1871) Zeitschrift für Wissenschaftliche Zoologie, 21, pp. 380-39