Hyperia Latreille 1823

Genus Hyperia Latreille, in Desmarest, 1823

Remarks

This genus has been revised by Bowman (1973), who provides a key and very useful illustrations for each species. Bowman recognised eight species, one of which, H. antarctica Spandl, 1927, is now regarded a synonym of H. spinigera Bovallius, 1889 (Thurston 1977). Two additional species have been described more recently; H. bowmani Vinogradov, 1976 and H. curticephala Vinogradov & Semenova, 1985.

Recently, I established that Oniscus quadricornis Fabricius, 1775 is most likely H. medusarum (Müller, 1776), and that the description of Fabricius is based solely on drawings by Sydney Parkinson held in the BMNH (Zeidler 1995). This species was listed only once in the literature (Fabricius 1781) before Fabricius (1787) realised that his species might be the same as H. medusarum. This synonymy seems to have been accepted by later naturalists but, probably because O. quadricornis was an inadequately described species, it was not recognised as the senior synonym. Stebbing (1888) also accepted the above synonymy but, like his predecessors, did not realise that Fabricius’s species was first published in 1775 and thus has priority. Similarly Bovallius (1889) gives a list of synonyms of H. medusarum but erroneously cites O. quadricornis Fabricius, 1781. Although Fabricius’s name has priority his species cannot be determined with certainty and the name has not been in use since 1781 (Fabricius 1781). Hyperia medusarum, on the other hand, is a well­established species and the name should be maintained to conserve nomenclatural stability.

Subsequently a syntype of Hyperia latreillii Milne­Edwards, 1830 (later corrected to H. latreillei) was discovered in the ANSP (CA 2697), in the Guérin­Méneville collection (No. 431) (Zeidler 1997). The specimen was identified tentatively as H. galba (Montagu, 1813), rather than the closely related species H. medusarum, with which H. latreillei has been synonymised in the past (Bowman 1973). Milne­Edwards (1830) gave the type locality of his species as the Bay of Biscay. But H. medusarum is a more northerly species than H. galba, being confined to the northern part of the North Sea (Schellenberg 1942), and extending south to about 52°N, off the west coast of Ireland, but with a single record at 48°N, southwest of Ireland (Stephensen 1924). Hyperia galba, on the other hand, extends farther south in the Atlantic than H. medusarum, reaching at least to the latitude of the coast of Spain (Alvarado 1955). Assuming that the locality data for H. latreillei, given by Milne­Edwards (1830), is correct then his species is more likely to be H. galba, as is supported by the examination of the syntype. Thus, in the absence of contrary evidence H. latreillei should be considered a synonym of H. galba rather than H. medusarum as has been assumed by Bowman (1973). Sars (1895), Norman (1900), Tattersall (1906) and Chevreux and Fage (1925) also regard H. latreillei a synonym of H. galba.

The gelatinous plankton associates of Hyperia are summarised by Thurston (1977) and Laval (1980). Most are with medusae, and Laval (1980) even suggests that records of associations with other gelatinous plantation such as salps and ctenophores may be erroneous. However, the association of H. gaudichaudii Milne­Edwards, 1840 with the ctenophore, Beroe sp. has been confirmed recently, and previous records of similar associations should not be dismissed (Zeidler & Gowlett­Holmes 1998).

Apart from Bowman (1973) and Laval (1980), additional biological information is provided for H. galba by Bowman et al. (1963), Metz (1967) and Dittrich (1987, 1988, 1992), for H. macrocephala by White and Bone (1972 – as H. galba), and for H. spinigera by Thurston (1977).

Bowman (1973) and Vinogradov et al. (1982) provide distributional data for the species.

Species: Hyperia medusarum (Müller, 1776); H. galba (Montagu, 1813); H. gaudichaudii Milne­Edwards, 1840; H. macrocephala (Dana, 1853); H. spinigera Bovallius, 1889; H. crassa Bowman, 1973; H. leptura Bowman, 1973; H. bowmani Vinogradov, 1976; H. curticephala Vinogradov & Semenova, 1985.