Accessibility / Report Error

Sexual dimorphism in Aegla marginata (Decapoda: Anomura)

André Trevisan Murilo Zanetti Marochi Marcelo Costa Sandro Santos Setuko Masunari About the authors


A study on sexual dimorphism in Aegla marginata was conducted using geometric morphometric methods. The carapace of 47 females and 75 males and the left and right cheliped propodus of 29 females and 40 males were analyzed. Eighteen landmarks were established in the carapace and 10 in the cheliped propodus. A Generalized Procrustes Analysis based on landmark configurations was used to separate the components of size and shape. A Student t-test was used to determine whether statistically significant sexual dimorphism was shown by the carapace and the cheliped propodus. The variation in the shape of the structures was evaluated with a discriminant analysis. Our results show that there is no sexual dimorphism in the carapace of A. marginata. However, the size of the propodus differed statistically between the sexes. The carapace shape differed between the sexes: the females showed a wider posterior area and a narrower anterior area than the males. The shape of the cheliped propodus also differed between the sexes: overall, the females had a longer and narrower cheliped propodus than the males. The variations in the carapace shape found in this study confirm the results of other studies on aeglid morphology; however, the information presented by this study regarding variation in the shape of the cheliped propodus is new to the literature. The geometric morphometric approach applied in this study provided useful tools for achieving the proposed objectives.

Aeglidae; carapace; cheliped; geometric morphometrics; sexual size dimorphism; sexual shape dimorphism

  • Abraham, J.N. 1998. La saboteuse: An ecological theory of sexual dimorphism in animals. Acta Biotheoretica, 46: 23-35.
  • Adams, D.C. and Rohlf, F.J. 2000. Ecological character displacement in plethodon: biomechanical differences found from a geometric morphometric study. Proceedings of the National Academy of Sciences of the United States of America, 97(8): 4106-4111.
  • Adams, D.C.; Rohlf, F.J and Slice, D.E. 2004. Geometric morphometrics: ten years of progress following the 'revolution'. Italian Journal of Zoology, 71: 5-16.
  • Almerão, M.; Bond-Buckup, G. and Mendonça Jr. M de S. 2010. Mating behavior of Aegla platensis (Crustacea, Anomura, Aeglidae) under laboratory conditions. Journal of Ethology, 28(1): 87-94.
  • Anastasiadou, C.; Liasko, R. and Leonardos, I.D. 2009. Biometric analysis of lacustrine and riverine populations of Palaemonetes antennarius (H. Milne Edwards, 1837) (Crustacea, Decapoda, Palaemonidae) from north-western Greece. Limnologica, 39: 244-254.
  • Bahamonde, N. and López, M.T. 1961. Estudios biológicos en la populación de Aegla laevis laevis (Latreille) de el Monte (Crustacea, Decapoda, Anomura). Investigaciones Zoológicas Chilenas, 7: 19-58.
  • Barría, E.M.; Sepúlveda, R.D. and Jara, C.G. 2011. Morphologic variation in Aegla Leach (Decapoda: Reptantia: Aeglidae) from central-southern Chile: interspecific differences, sexual dimorphism, and spatial segregation. Journal of Crustacean Biology, 31(2): 231-239.
  • Biagi, R. and Mantelatto, F.L. 2006. Relative growth and sexual maturity of the hermit crab Paguristes erythrops (Anomura, Diogenidae) from South Atlantic. Hydrobiologia, 559(1): 247-254.
  • Bigarella, J.J. 1978. A Serra do Mar e a porção ocidental do Estado do Paraná. Curitiba. Governo do Paraná, Secretaria de Estado do Planejamento e Associação de defesa e Educação Ambiental. 248p.
  • Bond-Buckup, G. and Buckup, L. 1994. A família Aeglidae (Crustacea, Decapoda, Anomura). Arquivos de Zoologia, 32: 159-346.
  • Buckup, L. and Rossi, A. 1979. O gênero Aegla no Brasil (Crustacea, Decapoda, Anomura, Aeglidae. Revista Brasileira de Biologia, 37(4): 879-892.
  • Bueno, A.A.P.; Bond-Buckup, G. and Buckup, L. 2000. Crescimento de Aegla platensis em ambiente natural (Crustacea, Decapoda, Aeglidae). Revista Brasileira de Zoologia, 17(1): 43-49.
  • Bueno, S.L.S. and Shimizu, R.M. 2009. Allometric growth, sexual maturity, and adult male chelae dimorphism in Aegla franca (Decapoda: Anomura: Aeglidae). Journal of Crustacean Biology, 29(3): 317-328.
  • Castiglioni, D.S. and Negreiros-Fransozo, M.L. 2004. Comparative analysis of the relative growth of Uca rapax (Smith) (Crustacea, Ocypodidae) from two mangroves in São Paulo, Brazil. Revista Brasileira de Zoologia, 21(1): 137-144.
  • Castiglioni, D.S. and Coelho, P.A. 2011. Determinação da maturidade sexual de Ucides cordatus (Crustacea, Brachyura, Ucididae) em duas áreas de manguezal do litoral sul de Pernambuco, Brasil. Iheringia, Série Zoologia, 101(1-2): 138-144.
  • Clabaut, C.; Bunje, P.; Salzburger, W. and Meyer, A. 2007. Geometric morphometric analyses provide evidence for the adaptive character of the Tanganyikan cichlid radiations. Evolution, 61: 560-578.
  • Clark P.F.; Neale M. and Rainbow P.S. 2001. A morphometric analysis of regional variation in Carcinus Leach, 1814 (Brachyura: Portunidae: Carcininae) with particular reference to the status of the two species C. maenas (Linnaeus, 1758) and C. aestuarii Nardo, 1847. Journal of Crustacean Biology, 21: 288-303.
  • Claude, J.; Pritchard, P.C.H.; Tong, H.; Paradis, E. and Auffray, J. 2004. Ecological correlates and evolutionary divergence in the skull of turtles: a geometric morphometric assessment. Systematic Biology, 53(6): 933-948.
  • Cohen, F.P.A.; Takano, B.F.; Shimizu, R.M. and Bueno, S.L.S. 2011. Life cycle and population structure of Aegla paulensis (Decapoda: Anomura: Aeglidae). Journal of Crustacean Biology, 31(3): 389-395.
  • Collins, P.A.; Giri, F. and Williner, V. 2008. Sexual maturity and ontogenetic shape variations in the freshwater anomuran crab, Aegla uruguayana (Decapoda, Aeglidae). Invertebrate Reproduction and Development, 52(1-2): 113-119.
  • Colpo, K.D.; Ribeiro, L.D. and Santos, S. 2005. Population biology of the freshwater Anomura Aegla longirostri (Aeglidae) from south Brazilian streams. Journal of Crustacean Biology, 25(3): 495-499.
  • Cordeiro-Estrela, P.; Baylac, M.; Denys, C. and Marinho-Filho, J. 2006. Interspecific patterns of skull variation between sympatric Brazilian vesper mice: geometric morphometrics assessment. Journal of Mammalogy, 87(6): 1270-1279.
  • Dana, J.D. 1852. Crustacea. Part 1. In: United States Exploring Expedition during the Years 1838, 1839, 1840, 1841, 1842, Under the Command of Charles Wilkes, U.S.N., S.1. Vol. 13: 475-478.
  • Fairbairn, D.J. and Preziosi, R.F. 1994. Sexual selection and evolution of allometry for sexual size dimorphism in the water strider, Aquarius remigis The American Naturalist, 144(1): 101-118.
  • Fairbairn, D.J. and Preziosi, R.F. 1996. Sexual selection and evolution of sexual size dimorphism in the water strider, Aquarius remigis The American Naturalist, 144(1): 101-118.
  • Fernandes, C.S.; Gregati, R.A. and Bichuette, M.E. 2010. The first record of external abnormalities in the subterranean Aegla marginata Bond-Buckup and Buckup, 1994 (Crustacea: Decapoda: Aeglidae), from a karst area of Southeastern Brazil. Subterranean Biology, 8: 33-38.
  • Finney, W.C. and Abele, L.G. 1981. Allometric variation and sexual maturity in the obligate coral commensal Trapezia ferruginea Latreille (Decapoda, Xanthidae). Crustaceana, 41: 113-130.
  • Flores, A.A.V.; Saraiva, J. and Paula, J. 2002. Sexual maturity, reproductive cycles and juvenile recruitment of Perisesarma guttatum (Brachyura, Sesarmidae) at Ponta Rasa mangrove swamp, Inhaca Island, Mozambique. Journal of Crustacean Biology, 22(1): 143-156.
  • Fornel, R.; Cordeiro-Estrela, P. and De Freitas, T.R.O. 2010. Skull shape and size variation in Ctenomys minutus (Rodentia: Ctenomyidae) in geographical, chromosomal polymorphism, and environmental contexts. Biological Journal of Linnean Society, 101: 705-720.
  • Fransozo, A.; Costa, R.C.; Reigada, A.L.D. and Nakagaki, J.M. 2003. Population structure of Aegla castro Schmitt, 1942 (Crustacea: Anomura: Aeglidae) from Itatinga (SP), Brazil. Acta Limnologica Brasiliensis, 15(2): 13-20.
  • Garvey, J.E. and Stein, R.A. 1993. Evaluating how chela size influences the invasion potential of an introduced crayfish (Orconectes rusticus). American Midland Naturalist, 129: 172-181.
  • Gibbes, L.R. 1850. On the carcinological collections of the cabinets of natural history in the United States; with an enumeration of the species contained therein, and descriptions of new species. Proceedings of the American Association for the Advancement of Science, 3: 165-201.
  • Giesel, J.T. 1972. Sex ratio, rate of evolution, and environmental heterogeneity. American Naturalist, 106: 380-387.
  • Giri, F. and Collins, P. 2004. A geometric morphometric analysis of two sympatric species of the family Aeglidae (Crustacea, Decapoda, Anomura) from the La Plata basin. Italian Journal of Zoology, 71: 85-88.
  • Giri, F. and Loy, A. 2008. Size and shape variation of two freshwater crabs in Argentinean Patagonia: the influence of sexual dimorphism, habitat, and species interactions. Journal of Crustacean Biology, 28(1): 37-45.
  • Gonçalves, R.S.; Castiglioni, D.S. and Bond-Buckup, G. 2006. Ecologia populacional de Aegla franciscana (Crustacea, Decapoda, Anomura) em São Francisco de Paula, RS, Brasil. Iheringia, Série Zoologia, 96(1): 109-114.
  • Grandjean, F.; Romain, D.; Avila-Zarza, C.; Bramard, M.; Souty-Grosset, C. and Mocquard, J.P. 1997. Morphometry, sexual dimorphism and size at maturity of the white-clawed crayfish, Austropotamobius pallipes pallipes (Lereboullet) from a wild French population at Deux-Sevres (Decapoda, Astacidea). Crustaceana, 70: 31-44.
  • Green, A.J. 2000. The scaling and selection of sexually dimorphic characters: an example using the Marbled Teal. Journal of Avian Biology, 31: 345-350.
  • Gonzalez, P.N.; Perez, I.S. and Bernal, V. 2011. Ontogenetic allometry and cranial shape diversification among human populations from South America. The Anatomical Record, 294: 1864-1874.
  • Gould S.J. 1974. The origin and function of 'bizarre' structures: antler size and skull size in the 'irish elk' Megaloceros giganteus Evolution, 28: 191-220.
  • Hartnoll, R.G. 1974. Variation in growth patterns between some secondary sexual characters in crabs. Crustaceana, 27: 131-136.
  • Hartnoll, R.G. 1978. The determination of relative growth in Crustacea. Crustaceana, 34: 281-293.
  • Hartnoll, R.G. 1982. Growth, In: Bliss, D.E. (ed), The biology of Crustacea, Embriology, Morphology and Genetics. New York, Academic Press, Inc., Vol. 2: 111-196.
  • Hebling, N.J. and Rodrigues, W. 1977. Sobre uma nova espécie brasileira do gênero Aegla Leach, 1820 (Decapoda, Anomura). Papéis Avulsos de Zoologia, 30(19): 289-294.
  • Hedrick, A.V. and Temeles, E.J. 1989. The evolution of sexual dimorphism in animals: hypotheses and tests. Trends in Ecology and Evolution, 4: 136-138.
  • Hepp, L.U.; Fornel, R.; Restello, R.M.; Trevisan, A. and Santos, S. 2012. Intraspecific morphological variation in a freshwater crustacean Aegla plana (Anomura) in southern Brazil: effects of geographical segregation on carapace shape. Journal of Crustacean Biology, 32(4): 511-518.
  • Hobbs III, H.H. 1978 A new species of the South American genus Aegla from Paraná, Brazil (Crustacea: Anomura: Aeglidae). Proceedings of the Biological Society of Washington, 91(4): 982-988.
  • Katsikaros K. and Shine R. 1997. Sexual dimorphism in the tusked frog, Adelotus brevis (Anura: Myobatrachidae): the roles of natural and sexual selection. Biological Journal of the Linnean Society, 60: 39-51.
  • Klingenberg, C.P. and Leamy, L.J. 2001. Quantitative genetics of geometric shape in the mouse mandible. Evolution, 55(11): 2342-2352.
  • Klingenberg, C.P.; Barluenga, M. and Meyer, A. 2002. Shape analysis of symmetric structures: quantifying variation among individuals and asymmetry. Evolution, 56: 1909-1920.
  • Klingenberg, C.P. and Monteiro, L.R. 2005. Distances and directions in multidimensional shape spaces: implications for morphometric applications. Systematic Biology, 54: 678-688.
  • Klingenberg, C.P. 2011. MorphoJ: an integrated software package for geometric morphometrics. Molecular Ecology Resources, 11: 353-357.
  • Latreille, M. 1818. Crustacés, Arachnides et Insects. In: G. Cuvier (ed), Le règne animal distribué d'aprés son organisation: pour servir de base à l'histoire naturelle des animaux et d'introduction à l'anatomie comparée/par M. le cher, Cuvier. Avec figures, dessinées d'après nature. Paris. Vol. 3.
  • López, M.T. 1965. Estudios biologicos en Aegla odebrechtii paulensis, Schmitt (Crustacea, Decapoda, Anomura). Boletim de Zoologia, Faculdade de Filosofia, Ciências e Letras, 25: 301-315.
  • Maack, R. 1968. Geografia física do Estado do Paraná. Curitiba. BADEP. 350p.
  • Mantelatto, F.L. and Martinelli, J.M. 2001. Relative growth and sexual dimorphism of the South Atlantic hermit crab Loxopagurus loxochelis (Anomura, Diogenidae) from Ubatuba, Brazil. Journal of Natural History, 35(3): 429-437.
  • Mariappan, P.; Balasundaram, C. and Schmitz, B. 2000. Decapod crustacean cheliped: an overview. Journal of Biosciences, 25: 301-313.
  • Miranda, I. and Mantelatto, F.L. 2010. Sexual maturity and relative growth of the porcellanid crab Petrolisthes armatus (Gibbebs, 1850) from a remnant mangrove area. Nauplius, 18(1): 87-93.
  • Montague, C.L. 1980. A natural history of temperate Western Atlantic fiddler crabs (Genus Uca) with reference to their impact on the salt marsh. Contributions of Marine Science, 23: 25-55.
  • Monteiro, L.R.; Diniz-Filho, J.A.; Reis, S.F. and Araújo, E.D. 2002. Geometric estimates of heritability in biological shape. Evolution, 56(3): 563-572.
  • Morachiolli, N. 1994. Estudo da biologia de Aegla spp. Cavernícolas do Vale do Alto Ribeira, São Paulo (Crustacea: Anomura: Aeglidae). Master Thesis - Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil, 148pp.
  • Muino, R.; Fernandez, L.; Gonzalez-Gurraiaran, E.; Freire, J. and Vilar, J.A. 1999. Size at maturity of Liocarcinus depurator (Brachyura: Portunidae): a reproductive and morphometric study. Journal of the Marine Biological Association of the United Kingdom, 79: 29-303.
  • Noro, C.K. and Buckup, L. 2003. O crescimento de Aegla leptodactyla Buckup and Rossi (Crustacea, Anomura, Aeglidae). Revista Brasileira de Zoologia, 20(2): 191-198.
  • Oliveira, D. and Santos, S. 2011. Maturidade sexual morfológica de Aegla platensis (Crustacea, Decapoda, Anomura) no Lajeado Bonito, norte do estado do Rio Grande do Sul, Brasil. Iheringia, Série Zoologia, 101(1-2): 127-130.
  • Oyanedel, A.; Voldovinos, C.; Sandoval, N.; Moya, C.; Kiessling, G.; Salvo, J. and Olmos, V. 2011. The southernmost freshwater anomurans of the word: geographic distribution and new records of Patagonian eglids (Decapoda: Aeglidae). Journal of Crustacean Biology, 31(3): 396-400.
  • Pinheiro, M.A.A. and Fransozo, A. 1993. Relative growth of the speckled swimming crab Arenaeus cribrarius (Lamarck, 1818) (Brachyura, Portunidae), near Ubatuba, State of São Paulo, Brazil. Crustaceana, 65: 377-389.
  • R Development Core Team (2011). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL
  • Rocha, S.S. and Bueno, S.L.S. 2004. Crustáceos decápodes de água doce com ocorrência no Vale do Ribeira de Iguape e Rios Costeiros adjacentes, São Paulo, Brasil. Revista Brasileira de Zoologia, 21(4): 1001-1010.
  • Rodrigues, W. and Hebling, N.J. 1978. Estudos biológicos em Aegla perobae Hebling e Rodrigues, 1977 (Decapoda, Anomura). Revista Brasileira de Biologia, 38(2): 383-390.
  • Rohlf, F.J. and Marcus, L.F. 1993. A revolution in morphometrics. Trends in Ecology and Evolution, 8: 129-132.
  • Rohlf, F.J. 2010. tpsDig, digitize landmarks and outlines, version 2.16. Department of Ecology and Evolution, State University of New York at Stony Brook.
  • Rosenberg, M.S. 1997. Evolution of shape differences between the major and minor cheliped of Uca pugnax (Decapoda: Ocypodidae). Journal of Crustacean Biology, 17(1): 52-59.
  • Rufino, M.M.; Gaspar, M.B.; Pereira, A.M. and Vasconcelos, P. 2006a. Use of shape to distinguish Chamelea gallina and Chamelea striatula (Bivalvia: Veneridae): linear and geometric morphometric methods. Journal of Morphology, 267: 1433-1440.
  • Rufino, M.M.; Abello, P. and Yule, A.B. 2006b. Geographic and gender shape differences in the carapace of Liocarcinus depurator (Brachyura: Portunidae) using geometric morphometrics and the influence of a digitizing method. Journal of Zoology, 269: 458-465.
  • Santos, S.; Bond-Buckup, G.; Perez-Losada, M.; Santos-Bartholomei, M.L. and Buckup, L. 2009. Aegla manuinflata, a new species of freshwater anomuran (Decapoda: Anomura: Aeglidae) from Brazil, determined by morphological and genetic characters. Zootaxa, 2088: 31-40.
  • Santos, S.; Bond-Buckup, G.; Buckup, L.; Pérez-Losada, M.; Finley, M. and Crandall, K.A. 2012. Three new species of Aegla (Anomura) freshwater crabs from the upper Uruguay River hydrographic basin in Brazil. Journal of Crustacean Biology, 32 (4): 529-540.
  • Schmitt, W.L. 1942. The species of Aegla, endemic South American fresh-water crustaceans. Proceedings of the United States National Museum, 91: 431-524.
  • Shine, R. 1989. Ecological Causes for the evolution of sexual dimorphism: a review of the evidence. The Quarterly Review of Biology, 64(4): 419-461.
  • Silva, I.C. and Paula, J. 2008. Is there a better chela to use for geometric morphometric differentiation in brachyuran crabs? A case study using Pachygrapsus marmoratus and Carcinus maenas Journal of the Marine Biological Association of the United Kingdom, 88(5): 941-953.
  • Slatkin, M. 1984. Ecological causes of sexual dimorphism. Evolution, 38: 622-630.
  • Swiech-Ayoub, B.P. and Masunari, S. 2001. Flutuações temporal e espacial de abundância e composição de tamanho de Aegla castro Schmitt (Crustacea, Anomura, Aeglidae) no Buraco do Padre, Ponta Grossa, Paraná, Brasil. Revista Brasileira de Zoologia, 18(3): 1003-1017.
  • Teodósio, E.A.O. and Masunari, S. 2009. Estrutura populacional de Aegla schmitti (Crustacea: Anomura: Aeglidae) nos reservatórios dos Mananciais da Serra, Piraquara, Paraná, Brasil. Zoologia, 26(1): 19-24.
  • Trevisan, A. and Santos, S. 2011. Crescimento de Aegla manuinflata (Decapoda, Anomura, Aeglidae) em ambiente natural. Iheringia, Série Zoologia, 101(4): 336-342.
  • Trevisan, A. and Santos, S. 2012. Morphological sexual maturity, sexual dimorphism and heterochely in Aegla manuinflata (Anomura). Journal of Crustacean Biology, 32 (4): 519-527.
  • Viau, V.E.; López Greco, L.S.; Bond-Buckup, G. and Rodríguez, E.M. 2006. Size at onset of sexual maturity in anomuran crab, Aegla uruguayana (Aeglidae). Acta Zoologica, 87: 253-264.
  • Viscosi, V. and Cardini, A. 2011. Leaf morphology, taxonomy and geometric morphometrics: a simplified protocol for beginners. PLoSONE, 6(10): e25630. doi:10.1371/journal.pone.0025630.
  • Tzeng, T.D. 2004. Stock identification of sword prawn Parapenaeopsis hardwichii in the East China Sea and Taiwan Strait inferred by morphological variation. Fisheries Science, 70: 758-764.
  • Walker, K.A. and Fell, R.D. 2001. Courtship roles of male and female European earwigs, Forficula auricularia L. (Dermaptera: Forficulidae), and sexual use of forceps. Journal of Insect Behavior, 14: 1-17.

Publication Dates

  • Publication in this collection
    27 Jan 2015
  • Date of issue
    June 2012


  • Received
    09 May 2012
  • Accepted
    31 July 2012
Sociedade Brasileira de Carcinologia Instituto de Biociências, UNESP, Campus Botucatu, Rua Professor Doutor Antônio Celso Wagner Zanin, 250 , Botucatu, SP, 18618-689 - Botucatu - SP - Brazil