Styraconyx sargassi Thulin 1942

semi-cosmopolitan

This nominal species of the sargassi group has a long history of taxonomic confusion and misidentification (for more details see Kristensen & Higgins 1984a). At present, it is not possible to determine which records belong to this species and which do not. Kristensen & Higgins (1984a) suggested that this species may be restricted to algal associations and that specimens from other substrates should be examined very carefully. Additionally, the same authors rejected the suggestion by Renaud-Mornant (1967b) that the Chitwood (1951) specimens (marked as Bathyechiniscus tetronyx, Chitwood 1954, p. 325) from the Gulf of Mexico belong to S. sargassi. Rather, Kristensen & Higgins (1984a) stated that the Chitwood specimens are neither of these species, but probably belong to two different taxa. For the purposes of this paper we have included these records but identified them with bracketed question marks as it is not clear to which species they should be attributed. According to Kristensen & Higgins (1984a), the only records that are most likely to belong to S. sargassi are those of Rodriguez-Roda (1947, 1952) and Matthews 1938. In conclusion, and in agreement with Kristensen & Higgins (1984a), only the specimens from California and the type locality should be considered as valid, while other localities need confirmation.