Association between the mytilid Musculus viator and invasive tunicate Ascidiella aspersa in the San Matias gulf, Argentina

LAZARI, CAROLINA; DOLDAN, MARÍA DEL S.; CARIGNANO, ANGELICA; ORREGO, MARIA EUGENIA; MORSAN, ENRIQUE M.

AMERICAN MALACOLOGICAL BULLETIN

AMER MALACOLOGICAL SOC, INC

Año: 2018

0740-2783

Ascidiella aspersa in an exotic species widely distributed in the Sud-Occidental Atlantic coasts. In the Patagonia waters, it forms dense aggregations at El Sótano (San Matias Gulf). This tunicate hosts of a diverse number of organisms, including a mytilid species, Musculus viator. The aims of this study were to explore the presence of M. viator as an epibiotic organism of A. aspersa. During a benthic study, a total of 543 individuals of A. aspersa were collected from El Sótano and inspected. A total of 689 individuals of M. viator was extracted from the tunics of 42 specimens of A. aspersa. A maximum of 50 mytilid per tunicate was found. No relationship was found between the size of the tunicates and the size of M. viator. The high number of M. viator per A. aspersa individuals suggested that the tunicates invasion might have modified the mytilid population dynamics by offering adequate substrate.