<p><em>Tergipes tergipes</em> (Forskål, 1775)</p>
Atlantic coasts from Iceland and Norway to eastern U.S.A. and Spain, and around Mediterranean. Also recorded in S. Africa and Brazil (GBIF map).
Common all round Britain and Ireland, but overlooked as small size requires inspection of hydroids under magnification. Densities of 500 /m² recorded.
Lower shore and sublittorally to 20m. On hydroids growing on stones, Laminaria fronds, piers, floating structures and ships; even isolated small stones in pools in mud. Zig-zag digestive gland resembles stalk of Obelia geniculata (EML) which is frequently found, with T. tergipes on it, on fronds of Laminaria hyperborea growing in moderate wave exposure. Also on many other hydroids, such as Laomedia flexuosa (WoRMS) on sheltered shores and in estuaries down to 10 ppt salinity. Simultaneous hermaphrodite. Spherical or kidney-shape transparent spawn capsules , each containing about 30 white ova, produced throughout the year. Spawn capsules easier to detect, and about ten times more numerous, than adults. Short veliger stage of about a week before metamorphosis. Matures in 5 weeks, ovotestis developed in 2.5mm long specimens, so many generations p.a..
Eubranchus exiguus (Alder & Hancock, 1848)
Body (excluding appendages)