The infraorder Astacidea comprises five extant superfamilies, two of crayfish (Astacoidea and Parastacoidea), one of true lobsters (Nephropoidea), one of reef lobsters (the genus Enoplometopus), and a number of fossil taxa. As of 2009[update], the group contains 782 recognised species, over 400 of which are in the crayfish family Cambaridae. The members of the infra-order Glypheidea (containing numerous fossils and the two extant species Neoglyphea inopinata and Laurentaeglyphea neocaledonica) was formerly included here.
Members of the infraorder Astacidea are distinguished from most other decapods by the presence of chelae (claws) on each of the first three pairs of pereiopods (walking legs), the first of which is much larger than the remaining two pairs. The last two pairs of pereiopods are simple (without claws), except in Thaumastocheles, where the fifth pereiopod may have "a minute pincer".
- Sammy De Grave, N. Dean Pentcheff, Shane T. Ahyong; et al. (2009). "A classification of living and fossil genera of decapod crustaceans" (PDF). Raffles Bulletin of Zoology. Suppl. 21: 1–109.
- Gary Poore (2004). "Astacidea – scampi & crayfish". Marine Decapod Crustacea of Southern Australia: a Guide to Identification. CSIRO Publishing. pp. 159–167. ISBN 9780643099258.
- Lipke Holthuis (1991). "Infraorder Astacidea Latreille, 1802". FAO species catalogue Vol. 13: Marine Lobsters of the World (PDF). Rome, Italy: Food and Agriculture Organization. pp. 19–86. ISBN 92-5-103027-8.
- J. K. Lowry (October 2, 1999). "Astacidea (Decapoda, Eucarida, Malacostraca)". Crustacea, the Higher Taxa. Australian Museum. Archived from the original on July 5, 2008. Retrieved October 24, 2012.