Virilastacus retamali, a new species of burrowing parastacid, is described from the peatland in Rucapihuel located along the Coastal Cordillera from the province of Osorno, southern Chile. This is the third species of the genus Virilastacus described to date. It differs from V. araucanius and V. rucapihuelensis in the following morphological characters: 1) large eyes; 2) short rostral carina; 3...

The Copahue geothermal system is a natural extreme environment located at the northern end of the Cordillera de los Andes in Neuquén province in Argentina. The geochemistry and consequently the biodiversity of the area are dominated by the activity of the Copahue volcano. The main characteristic of Copahue is the extreme acidity of its aquatic environments; ponds and hot springs of moderate and...

Harold M. Monteclaro, Kazuhiko Anraku, Seiichi Uno, Jiro Koyama, Tatsuro Matsuoka, and Hong-Young Yan (2011) Sensitivity of crayfish Procambarus clarkii antennules to hydrodynamic stimuli is reduced during diazinon exposure. Zoological Studies 50(2): 145-154. In this study, the susceptibility of crustacean antennular mechanosensitivity to a pesticide was examined. We investigated the sensitivit...

Proctolin (Arg-Tyr-Leu-Pro-Thr-OH) and crayfish peptide "DF(2)" (Asp-Arg-Asn-Phe-Leu-Arg-Phe-NH(2)) enhance spontaneous contractions of isolated crayfish hindguts. Both peptides increase the frequency and amplitude of spontaneous, rapid contractions. Proctolin induces a slow contraction, which gives the appearance of an increase in overall tonus. DF(2) has no such effect. To determine whether t...

Discrepancies exist among spectral measurements of sensitivity of crayfish photoreceptors, their absorption in situ, and the number and absorption spectra of crayfish photopigments that are extracted by digitonin solutions. We have determined the photosensitivity spectrum of crayfish rhodopsin in isolated rhabdoms using long wavelength fluorescence emission from crayfish metarhodopsin as an int...

Spiroplasma eriocheiris disease control based on sensitive quantitative methods has become a priority. A SYBR Green real-time PCR that can simultaneously detect and quantify S. eriocheiris in the freshwater crayfish Procambarus clarkii was produced and evaluated. In the asymptomatic crayfish, hemolymph exhibited the statistically greatest number of S. eriocheiris copies indicating a tissue-spec...

Ireland is one of the few locations in Europe where non-indigenous North American crayfish species have not been introduced, and is a refuge for endangered white-clawed crayfish, Austropotamobius pallipes (Lereboullet, 1858). The parthenogenetic crayfish species Marmorkrebs, Procambarus fallax f. virginalis (Hagen, 1870), is sold in the pet trade in Ireland within the recorded range of A. palli...

Crayfish: Northern crayfish Orconectes virilis Louisiana crayfish Procambarus clarkii Water nymph crayfish Orconectes nais Rusty crayfish Orconectes rusticus Utah is inhabited by a single native crayfish known as the Pilose crayfish Pacifastacus (Hobbsastacus) gambelii. Its native range is in northern Utah’s Bear River, Weber River and Ogden River drainages and in the Raft River Mountain’s drai...