66
Systematic Account
Distribution
!he species is widely distributed in bays and
lDshore areas of both Pacific and Atlantic
coasts of North and South America. It has
recently been reported also for brackish
water lagoons in the Mediterranean Sea
(Gaudy and Vinas 1985). A. tansa has been
recorded for both the coasts of Chile (Vidal
1968; Arcos 1975; Hirakawa and Zama 1985' ,
Marin and Antezana 1985; Peterson et al.
1988) and Argentina (Ramirez 1969; Sabatini
1990). It was previously recorded in the
Straits of Magellan but only at Pacific and
central stations (Mazzocchi and lanora 1991).
In the present study, A. tansa was entirely
?bsent from the Pacific area but was present
lD subsurface waters of the Central and
Atlantic areas of the Straits.