PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-2 (2)
 

Clipboard (0)
None
Journals
Authors
Year of Publication
Document Types
author:("faulkner, Zen")
1.  Do Marmorkrebs, Procambarus fallax f. virginalis, threaten freshwater Japanese ecosystems? 
Aquatic Biosystems  2012;8:13.
Background
One marbled crayfish, Marmorkrebs, Procambarus fallax f. virginalis (Hagen, 1870), was discovered in a natural ecosystem in Japan in 2006. Because Marmorkrebs are parthenogenetic, they could establish a population from only a single individual, and thus pose a risk for becoming established in Japan, as they have in other countries. There are two major reasons to be concerned about the possibility of Marmorkrebs establishing viable populations in Japan. First, Japan’s only endemic crayfish, Cambaroides japonicus (De Haan, 1841), lives throughout Hokkaido and is endangered. Introduced Marmorkrebs are potential competitors that could further threaten C. japonicus. Second, Marmorkrebs live in rice paddies in Madagascar and consume rice. Marmorkrebs populations could reduce rice yields in Japan.
Results
We created five models in MaxEnt of the potential distribution of Marmorkrebs in Japan. All models showed eastern Honshu, Shikoku and Kyushu contain suitable habitats for Marmorkrebs. Hokkaido, the main habitat for C. japonicus, contained much less suitable habitat in most models, but is where the only Marmorkrebs in Japan to date was found.
Conclusions
Marmorkrebs appear to be capable of establishing populations in Japan if introduced. They appear to pose minimal threat to C. japonicus, but may negatively affect rice production.
doi:10.1186/2046-9063-8-13
PMCID: PMC3460755  PMID: 22738196
2.  Do Decapod Crustaceans Have Nociceptors for Extreme pH? 
PLoS ONE  2010;5(4):e10244.
Background
Nociception is the physiological detection of noxious stimuli. Because of its obvious importance, nociception is expected to be widespread across animal taxa and to trigger robust behaviours reliably. Nociception in invertebrates, such as crustaceans, is poorly studied.
Methodology/Principal Findings
Three decapod crustacean species were tested for nociceptive behaviour: Louisiana red swamp crayfish (Procambarus clarkii), white shrimp (Litopenaeus setiferus), and grass shrimp (Palaemonetes sp.). Applying sodium hydroxide, hydrochloric acid, or benzocaine to the antennae caused no change in behaviour in the three species compared to controls. Animals did not groom the stimulated antenna, and there was no difference in movement of treated individuals and controls. Extracellular recordings of antennal nerves in P. clarkii revealed continual spontaneous activity, but no neurons that were reliably excited by the application of concentrated sodium hydroxide or hydrochloric acid.
Conclusions/Significance
Previously reported responses to extreme pH are either not consistently evoked across species or were mischaracterized as nociception. There was no behavioural or physiological evidence that the antennae contained specialized nociceptors that responded to pH.
doi:10.1371/journal.pone.0010244
PMCID: PMC2857684  PMID: 20422026

Results 1-2 (2)