Psamathe Johnston, 1836: 14-16. — Pleijel 1998: 122 (syn., diagnosis). — Parapar et al. 2004: 232.
TYPE SPECIES. — Psamathe fusca Johnston, 1836, by monotypy.
DIAGNOSIS. — Psamathinae with two lateral antennae, without median antenna; no frontal tubercle; eyes present; nuchal organs separate; palpostyles ovoid, as long as palpophores; 8 pairs of tentacular cirri; without notochaetae; neurochaetae with simple and compound falcigers; pharynx without jaws, with marginal papillae.
DISTRIBUTION. — The species of Psamathe are only known from temperate localities in the Atlantic and Pacific and from the Antarctic, in shallow water, rocky or mixed bottoms. A new species, P. charpyi n. sp., is described from the Eastern tropical Pacific. The confusion in the identification of the species and their rarity might explain these sporadic records.
REMARKS
Pleijel (1998: 122-124) reinstated Psamathe Johnston, 1836, clarified its taxonomic history, and provided a list of species, including some new combinations (Pleijel 1998: 162- 163). There are currently five species in Psamathe: P. ancuda (Wesenberg-Lund, 1962) from Chile, P. cirrata Keferstein, 1862 from Normandy, France, P. fauveli (Averincev, 1972) from Antarctica, P. fusca Johnston, 1836 from the British coast in the English Channel, and P. haploseta (Perkins, 1984) from Florida, United States. On the other hand, Pleijel (1998) also regarded P. fusca and P. cirrata as synonyms, and Parapar et al. (2004: 232) followed it. However, despite the proximity of the type localities for these two species, both in the English Channel, there is no type material and topotype specimens for both species should be compared to corroborate this conclusion. There is one apparent difference regarding the length of ventral cirri according to the original descriptions, and some later illustrations (McIntosh 1908: pl. 69, fig. 16; Hartmann-Schröder 1996: 133, fig. 5b). In P. fusca it is short, not reaching the tip of neurochaetal lobes, whereas in P. cirrata it is longer, reaching the tip of neurochaetal lobes. The key below regards them as different species based on this feature.