Journal article

Publication year: 2014

Pages: 145-153

Journal: Hydrobiologia

Volume number: 739

Issue number: 1

DOI Link: https://doi.org/10.1007/s10750-013-1705-4

Publisher: Springer

Abstract: 

Freshwater crabs play an important role for the
diversification of shell morphologies in freshwater gastropods. For example,
the radiation of the freshwater crab genus Platythelphusa in
Lake Tanganyika is thought to have driven shell diversification of the lake’s
snail fauna, promoting the evolution of thalassoid shells. No comparable
thalassoid snails are known from Lake Malawi. Accordingly, it was hypothesized
that the lake’s only freshwater crab, Potamonautes lirrangensis,
is not a snail predator. We tested this hypothesis using feeding experiments
with specimens caught in the southern part of Lake Malawi. Individual crabs
were held in experimental containers offshore and were presented with various
food items overnight, after which ingestion frequency was recorded. Potamonautes lirrangensis can be
characterized as a scavenger that is opportunistically carnivorous. A
preference for fish and snail flesh could be observed, indicating a bias toward
carnivory. We observed occasional cracking of the shell in different snail
species, with frequent ingestion of artificially crushed specimens, suggesting
that crabs do attempt to feed on snails. However, the investigated Lake Malawi
gastropods appear to be partly protected against crab predation through thick-walled
and low-spired shells (especially Lanistes and Bellamya), obviating the evolution
of thalassoid shells carrying rims, ridges, or spines

Harvard Citation style: Weigand, A., Plath, M., Klussmann-Kolb, A., Schweyen, H., Agaba, J., Kyakuwa, A., et al. (2014) Prey preferences in captivity of the freshwater crab Potamonautes lirrangensis from Lake Malawi with special emphasis on molluscivory, Hydrobiologia, 739(1), pp. 145-153. https://doi.org/10.1007/s10750-013-1705-4

APA Citation style: Weigand, A., Plath, M., Klussmann-Kolb, A., Schweyen, H., Agaba, J., Kyakuwa, A., Tolo, C., Albrecht, C., Clewing, C., & und andere (Members of the Volkswagen Foundation Lake Malawi Field School 2012, C. (2014). Prey preferences in captivity of the freshwater crab Potamonautes lirrangensis from Lake Malawi with special emphasis on molluscivory. Hydrobiologia. 739(1), 145-153. https://doi.org/10.1007/s10750-013-1705-4