Marmorkrebs are cloning crayfish

“Marmorkrebs” is an informal name given to marbled crayfish that were discovered by hobbyists in Germany in the late 1990s. “Marmorkrebs” roughly translates from German as “marbled crab.” The scientific name for Marmorkrebs is Procambarus virginalis (previously Procambarus fallax f. virginalis). They are an asexual relative of slough crayfish (Procambarus fallax) that live across Florida and southern Georgia in the United States. The only known cases of Marmorkrebs in the wild are where they have been introduced by humans.

Marmorkrebs are parthenogenetic: they are all females, and reproduce without sex. This is the only decapod crustacean found that reproduces only this way, giving it incredible potential as a model organism for research. Some of the advantages of Marmorkrebs are that they are genetically identical, reproduce at high rates, and are easy to care for.

Marmorkrebs are invasive 

Marmorkrebs have been introduced in many countries, and have established populations in some. They can damage agriculture and threaten native species. Marmorkrebs should not be used for bait, kept in outdoor tanks or ponds (Marmorkrebs can migrate over land), or placed in any other situation where they could be released into natural ecosystems.

The European Union banned Marmorkrebs (i.e., possession, trade, transport, production, and release) and some other crayfish species in 2016. The United Kingdom retained this prohibition after its departure from the European Union in 2020. 

Japan banned breeding and selling Marmorkrebs (and other crayfish species) in 2020.

In North America, Marmorkrebs are prohibited in:

In 2022, one person in the US plead guilty to selling Marmorkrebs

Recent research papers


🆕 Kor G, Mengal K, Buřič M, Kozák P, Niksirat H. Granules of immune cells are the source of organelles in the regenerated nerves of crayfish antennae. Fish & Shellfish Immunology: in press, 108787. 

🔓 Lipták B, Zorić K, Patoka J, Kouba A, Paunović M. The aquarium pet trade as a source of potentially invasive crayfish species in Serbia. Biologia: in press.

🔓 Vogt G. Phenotypic plasticity in the monoclonal marbled crayfish is associated with very low genetic diversity but pronounced epigenetic diversity. Current Zoology zoac094, in press.

2023 research papers

🔓 Kor G, Mengal K, Buřič M, Kozák P, Niksirat H. 2023. Comparative ultrastructure of the antennae and sensory hairs in six species of crayfish. PeerJ 11: e15006.

Mengal K, Kor G, Kouba A, Kozák P, Niksirat H. 2022. Hemocyte coagulation and phagocytic behavior in early stages of injury in crayfish (Arthropoda: Decapoda) affect their morphology. Developmental & Comparative Immunology 141: 104618.

🔓 Vogt G. 2023. Environmental adaptation of genetically uniform organisms with the help of epigenetic mechanisms—An insightful perspective on ecoepigenetics. Epigenomes 7(1): 1.

2022 research papers

🆕 Aigner K. 2022. Ecology of marbled crayfish and possible management measures at fishing ponds in Salzburg. Master’s thesis, Department of Environment and Biodiversity, University of Salzburg.

Bláha M, Weiperth A, Patoka J, Szajbert B, Balogh ER, Staszny Á, Ferincz Á, Lente V, Maciaszek R, Kouba A. 2022. The pet trade as a source of non-native decapods: the case of crayfish and shrimps in a thermal waterbody in Hungary. Environmental Monitoring and Assessment 194(10): 795.

Bohman P, Edsman L, Mrugała A. 2022. Is this a Swedish signal crayfish or an alien marbled crayfish? Crayfish News 44(1): 1, 3-6.

🔓 Boštjančić LL, Francesconi C, Rutz C, Hoffbeck L, Poidevin L, Kress A, Jussila J, Makkonen J, Feldmeyer B, Bálint M, Schwenk K, Lecompte O, Theissinger K. 2022. Host-pathogen coevolution drives innate immune response to Aphanomyces astaci infection in freshwater crayfish: transcriptomic evidence. BMC Genomics 23(1): 600.

🔓 Brown NEM, Therriault TW. The hidden risk of keystone invaders in Canada: a case study using non-indigenous crayfish. Canadian Journal of Fisheries and Aquatic Sciences 79(9): 1479-1496. 

🔓 Dobrović A, Geček S, Klanjšček T, Haberle I, Dragičević P, Pavić D, Petelinec A, Boštjančić LL, Bonassin L, Theissinger K, Hudina S. 2022. Recurring infection by crayfish plague pathogen only marginally affects survival and growth of marbled crayfish. NeoBiota 77: 155-177.

Faiad S. 2022. Under what conditions can a novel invader (the marbled crayfish, Procambarus fallax f. virginalis) exert predation pressure on schistosome-competent snails? Master's thesis, School of Aquatic and Fisheries Sciences, University of Washington.

🔓 Gallardo B, Sutherland WJ, Martin P, Aldridge DC. Applying Fault Tree Analysis to biological invasions identifies optimal targets for effective biosecurity. Journal of Applied Ecology 59(10): 2553-2566.

Kaliszewicz A, Karaban K, Sierakowski M, Maciaszek R, Kur M, Pyffel Z, Wolny L, Chmiel K, Łuciuk P, Rusin P, Kowalczyk K. 2022. Effect of dietary supplementation with fatty acids on growth, survival, and fatty acid patterns in Procambarus clarkii and Procambarus virginalis: the first comparison of two invasive crayfish species. The European Zoological Journal 89(1): 123-134.

Katayama H, Toyota K, Tanaka H, Ohira T. 2022. Chemical synthesis and functional evaluation of the crayfish insulin-like androgenic gland factor. Bioorganic Chemistry 122: 105738.

🔓 Maciaszek R, Jabłońska A, Prati S, Wróblewski P, Gruszczyńska J, Świderek W. 2022. Marbled crayfish Procambarus virginalis invades a nature reserve: how to stop further introductions? The European Zoological Journal 89(1): 888-901.

🔓 Marn N, Hudina S, Haberle I, Dobrović A, Klanjšček T. 2022. Physiological performance of native and invasive crayfish species in a changing environment: insights from Dynamic Energy Budget models. Conservation Physiology 10(1): coac031.

🔓 Mojžišová M, Svobodová J, Kozubíková-Balcarová E, Štruncová E, Stift R, Bílý M, Kouba A, Petrusek A. 2022. Long-term changes in the prevalence of the crayfish plague pathogen and its genotyping in invasive crayfish species in Czechia. NeoBiota 74: 105–127. 

Sentis A, Veselý L, Let M, Musil M, Malinovska V, Kouba A. 2022. Short-term thermal acclimation modulates predator functional response. Ecology and Evolution 12(2): e8631.

🔓 Tresnakova N, Kubec J, Stara A, Zuskova E, Faggio C, Kouba A, Velisek J. 2022. Chronic toxicity of primary metabolites of chloroacetamide and glyphosate to early life stages of marbled crayfish Procambarus virginalis. Biology 11: 927.

Vogt G. 2022. Studying phenotypic variation and DNA methylation across development, ecology and evolution in the clonal marbled crayfish: a paradigm for investigating epigenotype-phenotype relationships in macro-invertebrates. The Science of Nature 109(1): 16.

Marmorkrebs blog

News and commentary here. Featured in The Open Lab 2008 anthology.


Portal for the Marmorkrebs genome is here.

 This site is maintained by Zen Faulkes and was last updated 1 January 2023.