Family PARASTACIDAE Huxley, 1879

Cherax preissii

Tenuibranchiurus glypticus

Euastacus armatus

Engaewa subcoerulea

Museums

Museum list

Regional Maps

Family PARASTACIDAE Huxley, 1879

Parastacidae Huxley, T.H. 1879. On the classification and the distribution of the crayfishes. Proceedings of the Zoological Society of London 1878: 752-788 [771, 775].
Austroastacidae Clark, E. 1936. The freshwater and land crayfishes of Australia. Memoirs of the National Museum of Victoria, Melbourne 10: 5-58 [8].
Euastacidae Riek, E.F. 1959. The Australian freshwater Crustacea. Monographiae Biologicae 8: 246–258 [255].

Taxonomic Decision for Synonymy

Hobbs, H.H., Jr 1974. Synopsis of the families and genera of crayfish. Smithsonian Contributions to Zoology No. 164: i-iii, 1-32 [18]
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 [22]

Introduction

The freshwater crayfish consist of two monophyletic groupings corresponding to the superfamilies Parastacoidea (the Southern Hemisphere crayfish) and Astacoidea (Northern Hemisphere crayfish). Parastacids have a Gondwanan distribution, being found in New Zealand, Madagascar, southern New Guinea and South America, but it is in Australia that they reach their greatest diversity. Of the 15 recognised genera, ten are known from Australia. All Australian genera are endemic except for Cherax which extends northwards into New Guinea. Of the approximately 160 recognised species, 142 are known only from Australia. Tenuibranchiurus glypticus, fully grown at about 4 cm in length, is one of the smallest crayfish known, while at the other end of the scale, Astacopsis gouldi from Tasmania, is the world's largest, measuring up to 76 cm long and weighing 4.5 kg.

The foundational work on Australian Parastacidae was undertaken by Dr Edgar Riek who published five papers between 1951 and 1972. Subsequently, several important works have revised, or contributed to, particular genera: Astacopsis (Hamr 1992); Cherax (Sokol 1988; Short 1991, 1993; Short & Davie 1993; Campbell et al. 1994); Gramastacus (Zeidler & Adams 1990); Engaeus (Horwitz 1990a, 1994); Engaewa (Horwitz & Adams 2000); Euastacus (Morgan 1986, 1988, 1989, 1997; Short & Davie 1993; various works by Coughran). A recent significant alteration to genus level taxonomy has seen the genus Parastacoides (sensu Sumner 1978) sunk into synonymy, and the creation of two new genera Spinastacoides and Ombrastacoides by Hansen & Richardson (2006). The colour field guide of McCormack (2008) for the freshwater crayfish of New South Wales is an excellent identification resource. Recently there has been interest in the phylogenetic relationships of Australian parastacids, using molecular genetics techniques (particularly for Euastacus), with important papers published by Crandall et al. (1995), Crandall & Fitzpatrick (1996), Lawler & Crandall (1998), Ponniah & Hughes (1998, 2004, 2006), and Shull et al. (2005).

The ecology and conservation of parastacids is also receiving some much needed attention with interesting publications from Horwitz & Richardson (1986), Horwitz (1990b), Merrick (1995), and most recently, important assessments by O’Brien (2007), Coughran & Furze (2010), and Furze & Coughran (2011a,b,c). Euastacus species are considered to be under greatest threat from anthropomorphic impacts, including climate change, because of their unique biogeography, with narrow home ranges and often with distributions restricted to single mountain top catchments (particularly towards the tropics). The assessment of the conservation status of Australian Euastacus under IUCN criteria by Coughran & Furze (2010) reported four species as 'Endangered' and a further eight species as 'Critically Endangered'. However, as yet no specific conservation measures are in place for any Euastacus species. Research is needed, and should include population assessment and monitoring, biological and life history information, habitat requirements, investigations into thermal tolerance, and resilience to effects of exotic species (Coughran & Furze 2010).

Diagnosis

Small to moderately large crayfish. Carapace lacking dorsomedian, longitudinal suture or ridge in cardiac and posterior gastric regions. Sternal plate between fifth pereiopods not fused with sternal complex anteriorly. Telson never completely divided by transverse suture; exopod of uropods with transverse suture. Podobranchiae of first three pereiopods not differentiated into branchial and epipoditic portions and lacking bilobed plaited laminae; epipodite of first maxilliped usually with branchial filaments. Articles of lateral ramus of antennule never with more than one cluster of asthetascs. First pleopod absent in both male and female; second pleopod similar to third. Eggs large, larvae hatching as miniatures of adult. Restricted to freshwater. (After Hobbs 1974).