Mandibles of representatives of the Holarctic crayfish families Astacidae, Cambaridae, and Cambaroididae were examined using SEM, and the results were analyzed in a phylogenetic framework. The intraspecific variability of the incisor process was found to be higher than its interspecific variability, mainly due to extensive abrasion of its ridge during intermolt periods. The plesiomorphic state of the crayfish mandibles highlights the dentate-crenate type of the incisor process and the extensive ribbed molar field with a multicuspidate caudal part, typical of the two parastacid crayfish examined for comparison. For Holarctic crayfish, the initial evolutionary type of the incisor is also the dentate-crenate one, but the molar field has a bowl-shaped caudal part and reduced cephalic part, both of which have been shown, for example, for Cambaroides. Similar mandibles are also widely present in American cambarids, which further evolved a blade-like incisor process (some Faxonius spp.) or a tricuspidate or double-bladed caudal molar field (some Procambarus spp.). The molar field in Astacidae crayfish is subdivided and rugose. The results of the present study indicate that little phylogenetic information is conveyed by the mandible shape at the species or genus level. Evolutionary changes are indicated mainly on the level of the main crayfish families. RESEARCH HIGHLIGHTS: Mandible shape can be an additional characteristic to distinguish crayfish families and selected genera. Obvious differences exist in the molar process rather than in the incisor ridge.

Faculty of Science Department of Biology and Ecology and Institute of Environmental Technologies University of Ostrava Ostrava Czech Republic

See more in PubMed

Ahn, D. H., Kawai, T., Kim, S., Rh, H. S., Jung, J. W., Kim, W., … Min, G. (2006). Phylogeny of northern hemisphere freshwater crayfishes based on 16S rRNA gene analysis. Korean Journal of Genetics, 28(2), 185-192.

Alcorlo, P., Geiger, W., & Otero, M. (2004). Feeding preferences and food selection of the red swamp crayfish, Procambarus clarkii, in habitats differing in food item diversity. Crustaceana, 77(4), 435-453.

Andrews, E. A. (1907). The young of the crayfish Astacus and Cambarus. Smithsonian Contributions to Knowledge, 35(1718), 1859-1956.

Bentov, S., Zaslansky, P., Al-Sawalmih, A., Masic, A., Fratzl, P., Sagi, A., … Aichmayer, B. (2012). Enamel-like apatite crown covering amorphous mineral in a crayfish mandible. Nature Communications, 3, 839.

Bouchard, R. W. (1977). Morphology of the mandible in Holarctic crayfishes (Decapoda: Astacidae and Cambaridae): Ecological and phylogenetic implications. Freshwater Crayfish, 3, 425-452.

Braband, A., Kawai, T., & Scholtz, G. (2006). The phylogenetic position of the east Asian freshwater crayfish Cambaroides within the northern hemisphere Astacoidea (Crustacea, Decapoda, Astacida) based on molecular data. Journal of Zoological Systematics and Evolutionary Research, 44(1), 17-24.

Bracken, H. D., Toon, A., Felder, D. L., Martin, J. W., Finley, M., Rasmussen, J., … Crandall, K. A. (2009). The decapod tree of life: Compiling the data and moving toward a consensus of decapod evolution. Arthropod Systematics & Phylogeny, 67(1), 99-116.

Bracken-Grissom, H. D., Ahyong, S. T., Wilkinson, R. D., Feldman, R. M., Schweitzer, C. E., Breinholt, J. W., … Crandall, K. A. (2014). The emergence of lobsters: Phylogenetic relationships, morphological evolution and divergence time comparisons of an ancient group (Decapoda: Achelata, Astacidea, Glypheidea, Polychelida). Systematic Biology, 63(4), 457-479.

Breinholt, J. W., Perez-Losada, M., & Crandall, K. A. (2009). The timing of the diversification of the freshwater crayfish. In J. W. Martin, K. A. Crandall, & D. L. Felder (Eds.), Decapod crustacean phylogenetics (pp. 343-356). New York, NY: CRC Press, Taylor & Francis.

Caine, E. A. (1975). Feeding and masticatory structures of six species of crayfish Procambarus (Decapoda, Astacidae). Forma et Functio, 8(1), 49-66.

Chambers, P. A., Hanson, J. M., Burke, J. M., & Prepas, E. E. (1990). The impact of the crayfish Orconestes virilis on aquatic macrophytes. Freshwater Biology, 24(1), 81-91.

Chucholl, C. (2012). Understanding invasion success: Life-history traits and feeding habits of the alien crayfish Orconectes immunis (Decapoda, Astacida, Cambaridae). Knowledge and Management of Aquatic Ecosystems, 404, 04.

Chybowski, L. (2007). Morphometrics, fecundity, density and feeding intensity of spiny-cheek crayfish, Orconectes limosus (Raf.) in natural conditions. Archives of Polish Fisheries, 15(3), 175-241.

Correia, A. M. (2003). Food choice by the introduced crayfish Procambarus clarkii. Annales Zoologici Fennici, 40(6), 517-528.

Crandall, K. A. (2006). Applications of phylogenetics to issues in freshwater crayfish biology. Bulletin Français de la Pêche et de la Pisciculture, 380-381, 953-964.

Crandall, K. A., & De Grave, S. (2017). An updated classification of the freshwater crayfishes (Decapoda: Astacidea) of the world, with a complete species list. Journal of Crustacean Biology, 37(5), 615-653.

Crandall, K. A., Harris, D. J., & Fetzner, J. W., Jr. (2000). The monophyletic origin of freshwater crayfish estimated from nuclear and mitochondrial DNA sequences. Proceedings of the Royal Society of London B: Biological Sciences, 267(1453), 1679-1686.

Cronin, G., Lodge, D. M., Hay, M. E., Miller, M., Hill, A. M., Horvath, T., … Wahl, M. (2002). Crayfish feeding preferences for freshwater macrophytes: The influence of plant structure and chemistry. Journal of Crustacean Biology, 22(4), 708-718.

Díaz, D. C. (2009). Morphological analyses of modifications in signal crayfish mandible in relation to feeding habits (BSc thesis). Uppsala Universitet. 9 pp.

Factor, J. R. (1978). Morphology of the mouthparts of larval lobsters, Homarus americanus (Decapoda: Nephropidae), with special emphasis on their setae. The Biological Bulletin, 154(3), 383-408.

Franz, R., & Lee, D. S. (1982). Distribution and evolution of Florida's troglobitic crayfishes. Bulletin of the Florida State Museum Biological Sciences, 28(3), 53-78.

Gherardi, F., Acquistapace, P., & Santini, G. (2004). Food selection in freshwater omnivores: A case study of crayfish Austropotamobius pallipes. Archiv für Hydrobiologie, 159(3), 357-376.

Goddard, J. S. (1988). Food and feeding. In D. M. Holdich & R. S. Lowery (Eds.), Freshwater crayfish: Biology, management and exploitation (pp. 145-166). London, England: Chapman & Hall.

Grandjean, F., Tan, M. H., Gan, H. M., Lee, Y. P., Kawai, T., Distefano, R. J., … Austin, C. M. (2017). Rapid recovery of nuclear and mitochondrial genes by genome skimming from northern hemisphere freshwater crayfish. Zoologica Scripta, 46(6), 718-728.

Harlioğlu, M. M. (2000). Incisor ridge modification on the mandible in freshwater crayfish, Astacus leptodactylus. Aquaculture International, 8(5), 443-453.

Harlioğlu, M. M. (2008). A scanning electron microscopic study on the appendage morphology of Astacus leptodactylus (Eschscholtz, 1823) and Pacifastacus leniusculus (Dana, 1852) (Crustacea: Decapoda: Astacoidea). International Journal of Morphology, 26(4), 1035-1051.

Hobbs, H. H., Jr. (1987). A review of the crayfish genus Astacoides (Decapoda: Parastacidae). Smithsonian Contributions to Zoology, 443, 50.

Holdich, D. M. (2002). Background and functional morphology. In D. M. Holdich (Ed.), Biology of freshwater crayfish (pp. 3-29). Oxford, England: Blackwell Science.

Holdich, D. M., & Reeve, I. D. (1988). Functional morphology and anatomy. In D. M. Holdich & R. S. Lowery (Eds.), Freshwater crayfish: Biology, management and exploitation (pp. 11-51). London, England: Chapman & Hall.

Huxley, T. H. (1880). The crayfish: An Introduction to the study of zoology. London, England: C. Kegan Paul & Co.

Johnson, G. T., Elder, J. F., Jr., Thompson, S. M., Hightower, P., & Bechler, D. (2011). Phylogeny of the freshwater crayfish subfamily Cambarinae based on 16S rDNA gene analysis. Current Trends in Ecology, 2, 97-113.

Kawai, T. (2012). Morphology of the mandible and gill of Asian freshwater crayfish Cambaroides (Decapoda: Cambaridae) with implications for their phylogeny. Journal of Crustacean Biology, 32(1), 15-23.

Kawai, T., Labay, V. S., & Filipová, L. (2013). Taxonomic re-examination of Cambaroides (Decapoda: Cambaridae) with a re-description of C. schrenckii from Sakhalin Island Russia and phylogenetic discussion of the Asian cambarids based on morphological characteristics. Journal of Crustacean Biology, 33(5), 702-717.

Loya-Javellana, G. N., & Fielder, D. R. (1997). Developmental trends in the mouthparts during growth from juvenile to adult of the tropical freshwater crayfish, Cherax quadricarinatus von martens, 1868 (Decapoda: Parastacidae). Invertebrate Reproduction & Development, 32(2), 167-175.

Momot, W. T. (1995). Redefining the role of crayfish in aquatic ecosystems. Reviews in Fisheries Science, 3(1), 33-63.

Nyström, P. (2002). Ecology. In D. M. Holdich (Ed.), Biology of freshwater crayfish (pp. 192-235). Oxford, England: Blackwell Science.

Owen, C. L., Bracken-Grissom, H. D., Stern, D., & Crandall, K. A. (2015). A synthetic phylogeny of freshwater crayfish: Insights for conservation. Philosophical Transactions of the Royal Society of London, Series Biological Sciences, 370(1662), 20140009.

Parkyn, S. M., Collier, K. J., & Hicks, B. J. (2001). New Zealand stream crayfish: Functional omnivores but throphic predators? Freshwater Biology, 46(5), 641-652.

Reynolds, J. (2002). Growth and reproduction. In D. M. Holdich (Ed.), Biology of freshwater crayfish (pp. 152-184). Oxford, England: Blackwell Science.

Roth, B. M., Hein, C. L., & Vander Zaden, M. J. (2006). Using bioenergetics and stable isotopes to assess the trophic role of rusty crayfish (Orconectes rusticus) in lake littoral zones. Canadian Journal of Fisheries and Aquatic Sciences, 63(2), 335-344.

Sahlmann, C., Chan, T. -Y., & Chan, B. K. K. (2011). Feeding modes of deep-sea lobsters (Crustacea: Decapoda: Nephropidae and Palinuridae) in Northwest Pacific waters: Functional morphology of mouthparts, feeding behaviour and gut content analysis. Zoologischer Anzeiger, 250(1), 55-66.

Scalici, M., & Gibertini, G. (2007). Feeding habits of the crayfish Austropotamobius pallipes (Decapoda, Astacidae) in a brook of Latium (Central Italy). Italian Journal of Zoology, 74(2), 157-168.

Smart, A. C., Harper, D. M., Malaisse, F., Schmitz, S., Coley, S., & Gouder de Beauregard, A.-C. (2002). Feeding of the exotic Louisiana red swamp crayfish, Procambarus clarkii (Crustacea: Decapoda), in an African tropical lake: Lake Naivasha, Kenya. Hydrobiologia, 488(1-3), 129-142.

Taylor, C. A., & Soucek, D. J. (2010). Re-examining the importance of fish in the diets of stream-dwelling crayfishes: Implications for food web analyses and conservation. American Midland Naturalist, 163(2), 280-293.

Thomas, W. J. (1986). The paragnaths of Austropotamobius pallipes. Freshwater Crayfish, 6, 42-47.

Toon, A., Perez-Losada, M., Schweitzer, C. E., Feldmann, R. M., Carlson, M., & Crandall, K. A. (2010). Gondwanan radiation of the southern hemisphere crayfishes (Decapoda: Parastacidae): Evidence from fossils and molecules. Journal of Biogeography, 37(12), 2275-2290.

Vogt, G. (2002). Functional anatomy. In D. M. Holdich (Ed.), Biology of freshwater crayfish (pp. 53-141). Oxford, England: Blackwell Science.

Vojkovská, R., Horká, I., & Ďuriš, Z. (2014). The diet of the spiny-cheek crayfish Orconectes limosus in The Czech Republic. Central European Journal of Biology, 9(1), 58-69.