Subject Matters of Experiments and Observations of Water Animals in School Aquarium X (Rearing of Water Scorpions, Nepidae)

Lubomír Hanel


volume: 30
year: 2021
issue: 2
fulltext: PDF

online publishing date: 30/8/2021
DOI: 10.14712/25337556.2021.2.2
ISSN (Online): 2533-7556

Licence Creative Commons
Toto dílo podléhá licenci Creative Commons Uveďte původ 4.0 Mezinárodní License.


The rearing of two species of water scorpions (Heteroptera, Nepidae) in school aquaria is described in this contribution. The bodies of water scorpions are cylindrical (Ranatra linearis) or flattened (Nepa cinerea) with a siphon to pierce the water surface for air. Their bodies resemble sticks or leaves allowing them to remain motionless as sit-and-wait predators along the edges of ponds or streams waiting for prey to come within reach of their mantid-like forelegs. They are poor swimmers, but able to propel themselves with jerky leg motions. The body of Ranatra linearis is brown, typically 30–45 mm long. Their breathing tube tail is usually about as long as the body of the insect. The adults can fly. Stridulations and vibrations were reported for the forelegs of Ranatra with a femoral plectrum and coxal pars stridens. Nepa cinerea, like Ranatra linearis, live in ponds, slow running waters, stagnant water, canals, and wetlands with aquatic plants and plant debris. They feed upon aquatic animals, especially insects. Nepa cinerea are blackish brown in colour and usually measure 14–23 millimetres. Upon being disturbed, Nepa and Ranatra show thanatosis; they can stay motionless for a long time. The stings of both Nepa and Ranatra are painful for humans. Some experiments and observations suitable for school aquaria are suggested (e.g., habitat preference, food behaviour, thanatosis, reaction to light).


water scorpions, Ranatra linearis, Nepa cinerea, school aquarium, rearing, observations

fulltext (PDF )



BAILEY P. C. E. (1986): The Feeding Behaviour of a Sit-and-Wait Predator, Ranatra dispar, (Heteroptera: Nepidae): Description of Behavioural Components of Prey Capture, and the Effect of Food Deprivation on Predator Arousal and Capture Dynamics. Behaviour, 97, 1/2: 66-93.

BAKONYI G., PETÁK E., ERÖS T. & SÁLY P. (2016): Some morphological characteristics of the water scorpion Nepa cinerea (Heteroptera: Nepomorpha) are associated with habitat type. Acta Zoologica Academiae Scientiarum Hungaricae 62(4): 369-385.

BLOIS C. & CLOAREC A. (1983): Density-Dependent Prey Selection in the Water Stick Insect, Ranatra linearis (Heteroptera). Journal of Animal Ecology, 52(3): 849-866.

CLOAREC A. & JOLY D. (1988): Choice of perch by the water stick insect. Behavioural Processes, 17: 131-144.

FRANTSEVICH L. (1998): The coxal articulation in the insect striking legs: A comparative study. Journal of Morphology, 236(2): 127-128.<127::AID-JMOR4>3.0.CO;2-2

HAMILTON M. A. (1931): The morphology of the water scorpion, Nepa cinerea Linn. (Rhynchota, Heteroptera). Proceedings of the Zoological Society in London, 101(3): 1067-1136.

HANEL L. (2018a): Náměty na pokusy a pozorování vodních živočichů ve školním akváriu II (dýchání vodních živočichů). Biologie, chemie, zeměpis, 27(2): 11-21.

HANEL L. (2018b): Náměty na pokusy a pozorování vodních živočichů ve školním akváriu III (potravní chování vodních živočichů). Biologie, chemie, zeměpis, 27(4): 19-29.

HOLMES S. J. (1905): The reactions of Ranatra to light. Journal of Comparative Neurology and Psychology, 305-349.

HUDEC K., KOLIBÁČ J., LAŠTŮVKA Z., PEŇÁZ M. a kol. (2007): Příroda České republiky. Průvodce faunou. Academia, Praha, 440 s.

JAVOREK V. (1978): Kapesní atlas ploštic a křísů. Praha: Státní pedagogické nakladatelství, n. p., 400 s.

JOLY D. & CLOAREC A. (1980): The Influence of Light Intensity on Vertical Distribution in Ranatra linearis L. (Heteroptera : Nepidae). Journal of Ethology, 6: 111-119.

LELLÁK J., KOŘÍNEK V., FOTT J., KOŘÍNOVÁ J., PUNČOCHÁŘ P. (1972): Biologie vodních živočichů. Skriptum Přírodovědecké fakulty Univerzity Karlovy v Praze. SPN Praha, 218 s.

PACKAUSKAS R. & MCPHERSON J. E. (1986): Life history and laboratory rearing of Ranatra fusca (Hemiptera, Nepidae) with desriptions of immatures stages. Annals of the Entomological Society of America, 79(4): 566-571.

PETÁK E., ERÖS T. & BAKONYI G. (2014): Habitat use and movement activity of two common predatory waterbug species, Nepa cinerea L., 1758 and Ilyocoris cimicoides (L., 1758) (Hemiptera: Nepomorpha): field and laboratory observations. Aquatic Insects, 36, 3-4, 231-243.

POISSON R. (1957): Hétéropteres aquatiques. Paris, Paul Lechevalier.

RADA S. (2016): Splešťule blátivá – Nepa cinerea. Natura Bohemica. Dostupné na:

RYBAK J. I. (1971): Prezwodnik do rozpoznawania niektórych bezkregowych zwierzat slodkovodnych. Polska Akademia nauk, Warszawa, 75 s.

SINGH R. K. & SINGH P. (2004): Predatory Potential of Nepa cinerea against Mosquito Larvae in Laboratory Conditions. The Journal of Communicable Diseases, 36(2): 105-110.

ŠRETROVÁ M. (2019): Potravní biologie sladkovodních ploštic (Heteroptera: Nepomorpha). Bakalářská práce, Přírodovědecká fakulta Univerzity Karlovy, 38 s.

ŠTUSÁK J. M. (1980): Řád Ploštice – Heteroptera 133-155. In: Rozkošný R. (red.): Klíč vodních larev hmyzu. Československá akademie věd, Praha, 524 s.

VILÍMOVSKÁ L. (2012): Růst a variabilita jedinců splešťule blátivé (Nepa cinerea) (Heteroptera: Nepomorpha: Nepidae). Diplomová práce Pedagogické fakulty Jihočeské univerzity v Českých Budějovicích, 124 s.

WYNIGER R. (1974): Insektenzucht. Verlag Eugen Ulmer Stuttgart, 368 s.

We use cookies to analyse our traffic. More information