Distribution of invasive red alga Womersleyella setacea (Hollenberg) R.E. Norris (Rhodophyta, Ceramiales) in the Adriatic Sea

Abstract

       Womersleyella setacea (Hollenberg) R.E. Norris (Rhodophyta, Ceramiales) is an invasive macrophyte in the Mediterranean Sea, first recorded from the coast of Italy in 1986. This is a review of the geographic distribution and depth limits of W. setacea invasion in the Adriatic Sea since its first record in 1997. Algal turfs were collected and examined from different locations in the Croatian part of the Adriatic Sea from 2005 to 2009 by SCUBA diving and grab sampling. A total of 50 sites invaded by W. setacea were recorded in the Adriatic Sea; 40 new sites in this research and 10 from the literature records. Womersleyella setacea was recorded from 7 to 72 meters depth. Only sterile specimens without any reproductive structures were found. The magnitude of the invasion is discussed.