Insights on ecological and reproductive aspects of two cryptogenic peracarid crustaceans from Argentinean coasts

FRICKE, A.; BIANCALANA, F.; TONICELLI, G.; BERASATEGUI, A.; KOPPRIO, G.; GAUNA, M. C.; PARODI, ELISA R.

BRAZILIAN JOURNAL OF OCEANOGRAPHY

INST OCEANOGRAFICO

Lugar: São Paulo; Año: 2015 vol. 63 p. 194 - 206

1679-8759

Peracarid crustaceans belong to the most important agglomerating macrofauna in sedimentary habitats. The amphipod Monocorophium insidiosum Crawford, 1937 and the tanaid Tanais dulongii Audouin, 1926 are listed as invasive species. In the present study we investigated the ecology of M. insidiosum and T. aff. dulongii at the Argentinean coast. We breeded both crustaceans to study their fecundity and growth, and investigated their behavior and potential interspecific relations in four different laboratory experiments. We evaluated tube building capabilities (experiment 1), and tested gender specific responses of M. insdiosum to empty (experiment 2 and 3), and housed T. aff. dulongii tubes (experiment 4). Our results showed a high fecundity (three generations within four weeks) and growth rates (duplication of body lengths in two weeks) for M. insidiosum. Two tube construction strategies were distinguished: a tube changing behavior for M. insidiosum, showing higher construction activities for females, and a tube keeping behavior for T. aff. dulongii. Overall tanaid tubes were frequently claimed by M. insidiosum demonstrating a close interspecific relation and resulting in decreased sediment aggregating activity. Due to our observations it is likely that these invasive species are frequently distributed along the Patagonian Atlantic coast and will spread in future.