Eur. J. Entomol. 111 (3): 313-319, 2014 | 10.14411/eje.2014.048

Unbalanced sex ratio and triploidy in the genus Cyclocephala (Coleoptera: Scarabaeoidea: Dynastidae) in the Lesser Antilles: An example of parthenogenesis on islands?

Bernard DUTRILLAUX, Dominique PLUOT-SIGWALT, Anne-Marie DUTRILLAUX
UMR 7205 CNRS/MNHN, OSEB, Département Systématique et Evolution, Muséum National d'Histoire Naturelle, CP39, 16, rue Buffon, 75005 Paris, France; e-mails: bdutrill@mnhn.fr; dps@mnhn.fr; amdutril@mnhn.fr

Sex ratio and chromosomes studies were performed on six of the seven species of genus Cyclocephala present in the Lesser Antilles. Most sex ratios based on light trapping are skewed, with a frequent, but not exclusive, strong excess of females. These unbalances vary from species to species and island to island for the same species. Comparing old (seventies) and recent captures, the imbalances seem to increase with time. All of the 72 karyotyped males were diploid: 20,XY. Of the 15 females studied, one (C. dominicensis) was triploid: 30,XXX, a condition that only occurs in parthenogenetic species of beetles. We conclude that parthenogenesis is progressively developing within different sexual populations of Cyclocephala in the Lesser Antilles, which accounts for the excess of females recorded there. We propose that preexisting recessive mutations are the cause and that island colonization, by preventing panmictic reproduction, favours the expression of these recessive mutations. This would account for the accelerated occurrence of new characters (speciation /sub-speciation process), including unusual modes of reproduction such as parthenogenesis, and that several genetically related populations express these characters independently on different islands.

Keywords: Coleoptera, Scarabaeoidea, Dynastidae, Cyclocephala, sex ratio, triploidy, parthenogenesis, Lesser Antilles

Received: November 29, 2013; Accepted: March 6, 2014; Prepublished online: May 6, 2014; Published: July 14, 2014

Download citation

References

  1. Angus R.B. 1982: Separation of two species standing as Helophorus aquaticus (L.) (Coleoptera, Hydrophilidae) by banded chromosome analysis. - Syst. Entomol. 7: 265-281 Go to original source...
  2. Chalumeau F. 1983: Les coleopteres scarabaeides des Petites Antilles (Guadeloupe a Martinique). Lechevalier, Paris, 295 pp
  3. Dutrillaux A.-M. & Dutrillaux B. 2012: Hannetons, le retour. - Le Coleopteriste 15: 111-115
  4. Dutrillaux A.-M., Mercier J. & Dutrillaux B. 2007a: X-Y-autosome translocation, chromosome compaction, NOR expression and heterochromatin insulation in the scarabaeid beetle Dynastes hercules hercules. - Cytogenet. Genome Res. 116: 305-310 Go to original source...
  5. Dutrillaux A.-M., Xie H. & Dutrillaux B. 2007b: High chromosomal polymorphism and heterozygosity in Cyclocephala tridentata from Guadeloupe: chromosome comparison with some other species of Dynastinae (Coleoptera: Scarabaeidae). - Cytogenet. Genome Res. 119: 248-254 Go to original source...
  6. Dutrillaux A.-M., Lemonnier-Darcemont M., Darcemont C., Krpac V. & Fouchet P. 2009: Origin of the complex karyotype of the parthenogenetic grasshopper Saga pedo (Orthoptera: Tettigoniidae). - Eur. J. Entomol. 106: 477-483 Go to original source...
  7. Dutrillaux A.-M., Pluot-Sigwalt D. & Dutrillaux B. 2010: (Ovo-)viviparity in the darkling beetle, Alegoria castelnaui (Tenebrionidae: Ulomini), from Guadeloupe. - Eur. J. Entomol: 107: 481-485 Go to original source...
  8. Dutrillaux B., Chalumeau F., Dutrillaux A.-M., Giannoulis T. & Mamuris Z. 2013: Separation taxonomique en trois especes au sein d'une population de Cyclocephala tridentata Fabricius (Coleoptera: Scarabaeidae: Dynastinae), sur la base de criteres genetiques, chromosomiques et geographiques. - Ann. Soc. Entomol. Fr. (N.S.) 49: 61-67 Go to original source...
  9. Dybas H.S. 1966: Evidence for parthenogenesis in the featherwing beetles, with a taxonomic review of a new genus and eight new species (Coleoptera: Ptilidae). - Fieldiana (Zool.) 51: 11-52
  10. Endroedi S. 1985: The Dynastinae of the World. Series Entomologica 28, Dr W. Junk, Dordrecht, 800 pp
  11. Fuyama Y. 1986a: Genetics of parthenogenesis in Drosophila melanogaster I. The modes of diploidization in the gynogenesis induced by a male sterile mutant MS (3) K81. - Genetics 112: 237-248
  12. Fuyama Y. 1986b: Genetics of parthenogenesis in Drosophila melanogaster II. Characterization of a gynogenetically reproducing strain. - Genetics 114: 495-509
  13. Giannoulis T., Dutrillaux A.-M., Stamatis C., Dutrillaux B. & Mamuris Z. 2012: Cyclocephala (Coleoptera: Scarabaeidae: Dynastinae) evolution in Lesser West Indies indicates a Northward colonization by C. tridentata. - Bull. Entomol. Res. 102: 325-332 Go to original source...
  14. Gomez-Zurita J., Funk D.J. & Vogler A.P. 2006: The evolution of unisexuality in Calligrapha leaf beetles: molecular and ecological insights on multiple origins via interspecific hybridization. Evolution 60: 328-347 Go to original source...
  15. Hales F.D., Wilson A.C., Sloane M.A., Simon J.C., Le Galic J.F. & Sunnucks P. 2002: Lack of detectable genetic recombination on the X chromosome during the parthenogenetic production of female and male aphids. - Genet. Res. 79: 203-209 Go to original source...
  16. Harnden D.G. & Klinger H.P. (eds) 1985: An international System for Human Cytogenetic Nomenclature. S. Karger AG, Basel, 118 pp
  17. Howell W.M. & Black D.A. 1980: Controlled silver staining of nucleolus organizer regions with a protective colloidal developer: a one-step method. - Experientia 36: 1014-1015 Go to original source...
  18. Joly L.J. 1998: Una especie nueva de Cyclocephala de la Republica Dominicana y descripcion del macho de Cyclocephala vinosa Arrow 1937 de Jamaica Coleoptera: Melolonthidae: Dynastinae: Cyclocephalini. Bol. Entomol. Venezol. 131: 45-55
  19. Lachowska D., Rozek M. & Holecova M. 2008: New data on the cytology of parthenogenetic weevils (Coleoptera, Curculionidae). - Genetica 134: 235-242 Go to original source...
  20. Robertson J.G. 1966: The chromosomes of bisexual and parthenogenetic species of Calligrapha (Coleoptera: Chrysomelidae) with notes on sex ratio, abundance and egg number. - Can. J. Cytol. 8: 695-732 Go to original source...
  21. Smith S.G. & Virkki N. 1978: Coleoptera. In John B. (ed.): Animal Cytogenetics. Vol. 3. Insecta 5. Gegrueder Bornstraeger, Berlin, pp. 236-290
  22. Suomalainen E. 1962: Significance of parthenogenesis in the evolution of insects. - Annu. Rev. Entomol. 7: 349-366 Go to original source...
  23. Svestka M. 2006: Distributions of tribes of cockshafers of the genus Melolontha in forests of the Czeck Republic and the dependence of their swarming on temperature. - J. Forens. Sci. 52: 520-530
  24. Takenouchi Y. 1968: A chromosome study on bisexual and parthenogenetic races of Scepticus insularis Roelofs (Curculionidae, Coleoptera). - Can. J. Genet. Cytol. 10: 945-950 Go to original source...
  25. Tomiuk J. & Loeschcke V. 1992: Evolution of parthenogenesis in the Otiorhynchus scaber complex. - Heredity 68: 391-397 Go to original source...