A checklist of the Chilean Parastacidae (Decapoda, Astacidea)

Abstract

The family Parastacidae is represented in Chile by the genera Samastacus Riek, 1971, Parastacus Huxley, 1879, and Virilastacus Hobbs, 1991, and includes a total of six species. Its geographical distribution ranges from coastal areas to the Andean mountains, between the river Aconcagua (32°55′S 71°30′W) and the Taitao peninsula (46°30′S 74°30′W). These six species are: Samastacus spinifrons (Philippi, 1882), Parastacus pugnax (Poeppig, 1835), P. nicoleti (Philippi, 1882), Virilastacus araucanius (Faxon, 1914), V. rucapihuelensis Rudolph & Crandall, 2005 and V. retamali Rudolph & Crandall, 2007. All six species are endemic to Chile, with the exception of S. spinifrons which also inhabits Argentina and is the only species that inhabits lentic and lotic waters. The other five species are burrowers, inhabiting underground waters in semi-marshland zones where they build relatively complex burrows of varying depths. Present knowledge on the biology of these parastacids relates to: (a) taxonomy and phylogenetic relationships, (b) type and duration of embryonic and post-embryonic development, and (c) sexual system. Fragmentary studies have also been carried out on: (a) burrow morphology, (b) some physical/chemical parameters of water inside the burrows, (c) reproductive biology, and (d) aquaculture. These species are currently under threat, as a result of strong anthropogenic pressure which causes degradation of their respective habitats and, in some cases, such as S. spinifrons and P. pugnax, due to overexploitation as a human food source. Furthermore, in Chile there is no legislation to regulate the extraction, trade and transport of specimens. Only S. spinifrons is of interest for aquaculture purposes, in view of certain advantageous biological characteristics in comparison to other burrowing species. Nevertheless, certain intrinsic characteristics of parastacids, i.e., low fecundity and growth rate, late sexual maturity, very prolonged ovarian and embryonic development, together with deterioration of respective habitats and, in some species, overexploitation, have resulted in these species being classified as endangered Considering the aforementioned, it is important to study the life history, ecology and behaviour of each of these species, with the aim of compiling information that will permit the proposal and implementation of effective protection measures that, in turn, will ensure their conservation.