13 September 2018

Cover cray

Nice cover accompanying this blog post. It’s covering the Marmorkrebs genome paper that came out back in February, but better late than never! The photo is aces in any case.

External links

Decoding the mutant, all-female, self-cloning crayfish

Crayfish crimes

Prosecutions for anything to do with the aquarium trade is rare, but last week, news reported Justin Doyle Pierce, an American was prosecuted for selling crayfish as pets, in violation of the Lacey Act)

Pierce sold over $19,000 worth of crayfish illegally, and for this, he got a $500 fine, 20 hours of community service, and a year on probation. By my quick scan of the act, he could have received jail time and thousands of dollars in fines.

Is this sort of enforcement acting as a deterrent? It’s not clear. When someone can make that much money, the fine is little more than a clap on the wrist. The real penalty may not be the fine or the service, but the criminal record. Pierce wrote:

(T)his will result in my disqualification of future employment in areas related to wildlife and conservation.

External links

Feds pinch Camden County man for illegal crayfish sales
Overview of the Lacey Act (16 U.S.C. SS 3371-3378)
Lacey Act cases

Hossain and colleagues, 2018

Hossain MS, Patoka J, Kouba A, Buřič M. 2018. Clonal crayfish as biological model: a review on marbled crayfish. Biologia 73(9): 841-855. https://doi.org/10.2478/s11756-018-0098-2


Since the mid-twentieth century, numerous vertebrates and invertebrates have been used as model organisms and become indispensable tools for exploring a broad range of biological and ecological processes. Crayfish seem to be adequate models which resulted in their involvement in research. In the two decades since its discovery, ongoing research has confirmed that the marbled crayfish (Procambarus virginalis Lyko, 2017) is an ideal taxon in this regard, especially due to its almost continuous asexual reproduction providing a source of genetically identical offspring. This review provides an overview of the occurrence, biology, ecology, ethology, and human exploitation of marbled crayfish with primary focus on its use as a laboratory model organism as well as potential risks to native biota in case of its introduction. Genetic uniformity, ease of culture, and a broad behaviour repertoire fosters the use of marbled crayfish in epigenetics and developmental biology, as well as physiological, ecotoxicological, and ethological research. Marbled crayfish could be further exploited for basic and applied fields of science such as evolutionary biology and clonal tumour evolution. However, due to its high invasive potential in freshwater environments security measures must be taken to prevent its escape into the wild.

Keywords: model species • epigenetics • developmental biology • Procambarus virginalis • biological invasion

01 September 2018

Naboka and colleagues, 2018

Naboka A, Marenkov O, Kovalchuk J, Shapovalenko Z, Nesterenko O, Dzhobolda B. 2018. Parameters of the histological adaptation of Marmorkrebs Procambarus virginalis (Lyko, 2017) (Decapoda, Cambaridae) to manganese, nickel and lead ions pollution. International Letters of Natural Sciences 70: 24-33. https://doi.org/10.18052/www.scipress.com/ILNS.70.24


Manganese, lead and nickel are heavy metals, which are the primary fresh water toxic contaminants being in the most dangerous class of chemicals. Heavy metals cause functional disorders in the tissues and organs of hydrobionts, affecting their linear and weight indices, reproductive system, digestive and extraction organs. In our experiment on marbled crayfish Procambarus virginalis (Lyko, 2017) we studied the long-term effects of various concentrations of heavy metal ions on the physiological state and histostructure of tissues and organs. According to the results of research, it was found that among the studied heavy metals nickel ions influenced the weight indexes and mortality of crustaceans the most negatively. The results of morphometric studies on marbled crayfish indicate no significant differences between the control group and experimental one, but heavy metals influenced the form of the hepatopancerase lobes and the size of the lumen of the gland. Research on adipocytes of the connective tissue showed a significant difference between the size of cells under the influence of heavy metals. Dimensions of adipocytes fluctuated over a wide range from 144 μm2 to 537 μm2. In control group the adipocyte area was 406.96 μm2. Experimental studies of hemolymph showed that, under the influence of lead ions, a significant 1.4 times increase was observed in the area of hemolymph cells; when manganese and nickel were added, moderate decrease was observed in cells. It was found that under the influence of nickel, the area of round hyalinocytes has reduced by 1.7 times.

Keywords: Procambarus virginalis • glandulocytes • hepatopancreas • hemolymph • manganese • nickel • lead • crustaceans