First record of Naineris setosa (Verrill, 1900) (Annelida: Polychaeta: Orbiniidae) in the Western Mediterranean Sea

Abstract

The Asian kelp Undaria pinnatifida (Harvey) Suringar 1873 was found for the first time in Belfast Lough, Northern Ireland during 2012 and was probably established in 2013. This currently is the most northern locality in Europe. The recent expansion around Britain is likely to continue with further colonisation in Ireland and extension to Scotland. Conditions are suitable for colonisation of Celtic, North and perhaps Norwegian Sea coasts, where it is likely to become an important fouling organism on marinas, aquaculture equipment, and other structures. Its preponderance on marina and other pontoons suggests artificial structures are its preferred initial sites of colonisation.

First record of the alien polychaete Naineris setosa (Scolecida; Orbiniidae) in Tyrrhenian Sea (Western Mediterranean)

“…setosa is associated with stressed habitat or is a tolerant opportunistic species. In the Mediterranean Sea it has been previously collected from heavily polluted habitats, such as black anoxic muds (Blake and Giangrande 2011) and in these environments it was able to withstand salinities as high as 43.1 PSU (Khedhri et al 2014). In Santa Gilla lagoon, in the station where highest densities were achieved, both temperature and salinity fluctuated dramatically on a seasonal pattern, with temperatures ranging from 23.9°C in September to 11.6°C in December and salinity ranging from 37 (PSU) in September to 3.8 (PSU) in March; in none of these extreme environmental conditions population densities were observed to decrease.…”

“…), but its presence in two successive years indicated that the population was established, even though numbers were clearly decreasing from the first to the second year (Khedhri et al 2014).…”

“…At the point of time of publishing, the whole facility was closed down and the population became extinct (Blake and Giangrande 2011). Between 2012 and 2013, several specimens of N. setosa were collected from Boughrara lagoon (Tunisia) (Khedhri et al 2014). In this locality the species was reported to be less abundant compared to the population found in the farm facility in Brindisi (maximum reported density of 21 individuals m −2 vs. 500 individuals m −2…”

“…The material herein described was collected in a period running from two years before to one year later the first collecting in Tunisia (Khedhri et al 2014), revealing the first finding in a natural environment of the Mediterranean area. Indeed, the first record was reported from an aquaculture facility near Brindisi (Adriatic Sea, Italy) (Blake and Giangrande 2011) but at the time of the publication the farm was closed and the species was no longer collected.…”

Does increased connectivity with the Mediterranean Sea improve the ecological status of the macroinvertebrates in the lagoon of Boughrara (SW Mediterranean)?

“…Although molluscs still remain the principal group despite their decrease, polychaetes such as Euclymene droebachiensis, Glycera tridactyle and Naineris setosa (newly recorded by Khedhri et al 2014) have greatly increased followed by crustaceans including the amphipod Echinogammarus sp. and the decapod Carcinus aestuarii.…”