Tethya norvegica n.sp. Bowerbank, 1872: 121; Sarà et al., 1992: 212, figs. 1-5.
?Tethya lyncurium : Arndt, 1913: 113; Alander, 1935: 2
Tethya aurantium sensu Burton, 1930a: 496; 1931: 8.
Since this species was formerly considered a junior synonym of T . aurantium and was only recently re-instated as valid, many of the northern records of T . aurantium (e.g. those of Arndt, 1935) are uncertain and likely to be this species.