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Population genetics and systematics of theLeptasterias hexactis (Echinodermata: Asteroidea) species complex

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Abstract

Morphological characters and 14 enzyme loci were examined for 1 040 sea stars, currently recognized as forms ofLeptasterias hexactis, from Lynn Canal, Alaska, and Puget Sound, Washington, USA, between March 1988 and April 1989. Three morphologically and two genetically distinctLeptasterias forms were identified. The most common form found at both localities wasL. epichlora (Brandt)sensu Verrill.L. hexactis (Stimpson)sensu Verrill co-occurred withL. epichlora at all study sites and apparently hybridizes extensively withL. epichlora in the Puget Sound region, but rarely, if at all, in Alaska. The presumptive product of this hybridization morphologically resembledL. aequalis (Stimpson)sensu Fisher, and was conspicuously absent from Alaskan samples. Considerable genetic distance existed betweenL. epichlora andL. hexactis (Nei'sD=0.19±0.01) and moderate genetic differentiation occurred between populations of each species from Alaska and Washington (Weir and Cockerham'sF RT =0.29±0.04 forL. epichlora and 0.21±0.15 forL. hexactis). A significant (p<0.05) deficiency in the proportion of heterozygous individuals was found compared to Hardy-Weinberg expectations (Wright's fixation index,F ID=0.12±0.04 and 0.31±0.08 forL. epichlora andL. hexactis, respectively). However, mean observed heterozygosity for each species (0.09±0.03, 0.14±0.04 and 0.14±0.04 forL. epichlora, L. hexactis andL. aequalis, respectively) fell within the range of reported values for other asteroid species (ca. 0.04 to 0.37). The results of this study indicate that considerable genetic integrity is maintained betweenL. epichlora andL. hexactis, which warrants their recognition as distinct species despite their apparent hybridization in the Puget Sound region.

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Literature cited

  • Ayala, F. J. (1982). Population and evolutionary genetics. Benjamin/Cummings, Menlo Park, California

    Google Scholar 

  • Ayala, F. J., Hedgecock, D., Zumwalt, G. S., Valentine, J. W. (1973). Genetic variation inTridacna maxima, an ecological analog of some unsuccessful evolutionary lineages. Evolution, Lawrence, Kansas 27: 177–191

    Google Scholar 

  • Berger, E. M. (1973). Gene-enzyme variation in three sympatric species ofLittorina. Biol. Bull. mar. biol. Lab., Woods Hole 145: 83–90

    Google Scholar 

  • Berger, E. M. (1983). Population genetics of marine gastropods and bivalves In: Russell-Hunter, W. D. (ed.) The Mollusca. Vol. 6. Ecology. Academic Press, New York, p. 563–596

    Google Scholar 

  • Brandt, (1835). Prodromus descriptionis. Animalium Abh., Mertensio Observatorum. Fascic. I. (polypos, acalephas discophoras et siphonophoras nec non Echinodermata contineus). p. 270 [cited after Verrill (1914)]

  • Burton, R. S. (1983). Protein polymorphisms and genetic differentiation of marine invertebrate populations. Mar. Biol. Lett. 4: 193–206

    Google Scholar 

  • Bush, M. (1918). Key to the echinoderms of Friday Harbor, Washington. Publs Puget Sound mar. Biol. Stn 2: 17–44

    Google Scholar 

  • Bush, M. (1921). Revised key to the echinoderms of Friday Harbor, Washington. Publs Puget Sound mar. Biol. Stn. 3: 65–77

    Google Scholar 

  • Chambers, S. M. (1978). An electrophoretically detected sibling species of“Goniobasis floridensis” (Mesogastropoda: Pleuroceridae). Malacologia 178: 157–162

    Google Scholar 

  • Chia, F.-S. (1964). The developmental and reproductive biology of a brooding starfish,Leptasterias hexactis. Ph. D. dissertation. University of Washington

  • Chia, F.-S. (1966). Systematics of the six-rayed sea star,Leptasterias, in the vicinity of San Juan Island, Washington. Syst. Zool. 15: 300–306

    Google Scholar 

  • Dillon, R. T. Jr., Manzi, J. J. (1989). Genetics and shell morphology in a hybrid zone between the hard clamsMercenaria mercenaria andM. campechiensis. Mar. Biol. 100: 217–222

    Google Scholar 

  • Fisher, W. K. (1930). Asteroidea of the North Pacific and adjacent waters. Part 3. Forcipulata. Bull. U.S. natn. Mus. 76: 1–255

    Google Scholar 

  • Harris, H., Hopkinson, D.A. (1976). Handbook of enzyme electrophoresis in human genetics. North-Holland, Amsterdam

    Google Scholar 

  • Hedgecock, D. (1986). Is gene flow from pelagic larval dispersal important in the adaptation and evolution of marine invertebrates? Bull. mar. Sci. 39: 550–564

    Google Scholar 

  • Highsmith, R. C. (1985). Floating and algal rafting as potential dispersal mechanisms in brooding invertebrates. Mar. Ecol. Prog. Ser. 25: 169–179

    Google Scholar 

  • Koehn, R. K., Milkman, R., Mitton, J. B. (1976). Population genetics of marine pelecypods. IV. Selection, migration and genetic differentiation in the blue musselMytilus edulis. Evolution, Lawrence, Kansas 30: 2–32

    Google Scholar 

  • Kwast, K. E. (1989). Genetics and systematics of theLeptasterias hexactis species complex (Echinodermata: Asteroidea). M.S. thesis. Louisiana State University

  • Lambert, P. (1981). The sea stars of British Columbia. British Columbia Provincial Museum, Victoria

    Google Scholar 

  • Levene, H. (1949). On a matching problem arising in genetics. Ann. math. Statist. 20: 91–94

    Google Scholar 

  • Manwell, C., Baker, C. M. A. (1963). A sibling species of sea-cucumber discovered by starch gel electrophoresis. Comp. Biochem. Physiol. 10: 39–53

    Google Scholar 

  • McDonald, J. H., Koehn, R. K. (1988). The musselsMytilus galloprovincialis andM. trossulus on the Pacific coast of North America. Mar. Biol. 99: 111–118

    Google Scholar 

  • Nash, W. J., Goddard, M., Lucas, J. S. (1988). Population genetics of the crown-of-thorns starfish,Acanthaster planci (L.), in the Great Barrier Reef region. Coral Reefs 7: 11–18

    Google Scholar 

  • Nei, M. (1978). Estimation of average heterozygosity and genetic distance from a small number of individuals. Genetics, Austin, Tex. 89: 583–590

    Google Scholar 

  • Nishida, M., Lucas, J. S. (1988). Genetic differences between geographic populations of the crown-of-thorns starfish throughout the Pacific region. Mar. Biol. 98: 359–368

    Google Scholar 

  • SAS Institute, Inc. (1985). SAS user's guide: statistics. Version 5 ed. SAS Institute Inc., Cary, North Carolina

    Google Scholar 

  • Schopf, T. J. M., Murphy, L. S. (1973). Protein polymorphism of the hybridizing seastarsAsterias forbesi andAsterias vulgaris and implications for their evolution. Biol. Bull. mar. biol. Lab., Woods Hole 145: 589–597

    Google Scholar 

  • Selander, R. K., Smith, M. H., Yang, S. Y., Johnson, W. E., Gentry, J. B. (1971). Biochemical polymorphism and systematics in the genusPeromyscus. I. Variation in the old-field mouse (Peromyscus polionotus). Stud. Genet., Austin, Tex. 6: 49–90

    Google Scholar 

  • Smouse, P. E. (1972). The canonical analysis of multiple species hybridization. Biometrics 28: 361–371

    Google Scholar 

  • Sneath, P. H. A., Sokal, R. R. (1973). Numerical taxonomy — the principles and practice of numerical classification. W. H. Freeman & Co., San Francisco

    Google Scholar 

  • Steiner, W. W. M., Lisowski, E. A., Ostebur, D. (1977). Biochemical differences in sympatric colour morphs of an aquatic isopod (Asellus brevicauda). Comp. Biochem. Physiol. 56B: 371–374

    Google Scholar 

  • Stimpson, W. (1862a). On new genera and species of starfishes of the family Pycnopodidae (Asteracanthion, Müll. and Trosch.):Asterias hexactis. Proc. Boston Soc. nat. Hist. 8: p. 272

    Google Scholar 

  • Stimpson, W. (1862b). On new genera and species of starfishes of the family Pycnopodidae (Asteracanthion, Müll. and Trosch.):Asterias aequalis. Proc. Boston Soc. nat. Hist. 8: p. 273

    Google Scholar 

  • Thorpe, J. P., Beardmore, J. A., Ryland, J. S. (1978). Genetic evidence for cryptic speciation in the marine bryozoanAlcyonidium gelatinosum. Mar. Biol. 49: 27–32

    Google Scholar 

  • Tuttle, R. D., Lindahl, R. (1980). Genetic variability in 3 cooccurring forms of the starfish genusOthilia(=Echinaster). Experientia 36: 923–925

    Google Scholar 

  • Verrill, W. K. (1914). Monograph of the shallow-water starfishes of the North Pacific coast from the Arctic Ocean to California. Harriman Alaska Exped. (Smithson. Instn) 14: 1–408

    Google Scholar 

  • Weir, B. S., Cockerham, C.C. (1984). EstimatingF-statistics for the analysis of population structure. Evolution, Lawrence, Kansas 38: 1358–1370

    Google Scholar 

  • Woodruff, D. S., Staub, K. C., Upatham, E. S., Viyanant, V., Yuan, H.-C. (1988). Genetic variation inOncomelania hupensis: Schistosoma japonicum transmitting snails in China and the Philippines are distinct species. Malacologia 29: 347–361

    Google Scholar 

  • Zouros, E., Foltz, D. W. (1984). Possible explanations of heterozygote deficiency in bivalve molluscs. Malacologia 25: 583–591

    Google Scholar 

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Authors and Affiliations

  1. Department of Zoology and Physiology, Louisiana State University, 70803, Baton Rouge, Louisiana, USA

    K. E. Kwast, D. W. Foltz & W. B. Stickle

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  1. K. E. Kwast
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  2. D. W. Foltz
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Communicated by J. M. Lawrence, Tampa

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Kwast, K.E., Foltz, D.W. & Stickle, W.B. Population genetics and systematics of theLeptasterias hexactis (Echinodermata: Asteroidea) species complex. Mar. Biol. 105, 477–489 (1990). https://doi.org/10.1007/BF01316319

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