Leptometra celtica? ( M’Andrew & Barrett, 1857 )

Madeira, Patrícia, Kroh, Andreas, Cordeiro, Ricardo, De, António M., Martins, Frias & Ávila, Sérgio P., 2019, The Echinoderm Fauna of the Azores (NE Atlantic Ocean), Zootaxa 4639 (1), pp. 1-231 : 16

Leptometra celtica? ( M’Andrew & Barrett, 1857)

Reports for the Azores:

non Antedon phalangium (M̹ller, 1841)— Koehler 1909: 269;

non Leptometra phalangium (M̹ller, 1841)— Grieg 1932: 43;

Leptometra celtica ( M’Andrew & Barrett, 1857) — Marques 1980: 98;

Leptometra sp.—? $ Pérès 1992: 252.

Type locality: Sound of Skye , Scotland .

See: A.H. Clark & A.M. Clark (1967: 564–573, figs. 32c–g); A.M. Clark (1980: 193–195, fig. 2).

Occurrence: East Atlantic, from Faeroe channel to off Sierra Leone including the archipelagos of Madeira, Canaries, and the seamounts Seine and Gorringe (A.H. Clark & A.M. Clark 1967; A.M. Clark 1980).

Depth: 46– 1,279 m (A.H. Clark & A.M. Clark 1967); AZO:? 700 m ( Pérès 1992).

Habitat: mud, or sand, or gravel with mud (rarely on hard bottoms) (A.H. Clark & A.M. Clark 1967); can form dense beds ( Fonseca et al. 2014).

Remarks: Koehler (1909) included the Azores in the geographical distribution of Leptometra phalangium (M̹ller, 1841), a species regarded as endemic to the Mediterranean Sea ( Tortonese 1965). All reports of Leptometra phalangium from the Atlantic were a result of confusion with L. celtica , the only Leptometra species known to occur in the Atlantic (A.H. Clark & A.M. Clark 1967). Regardless, the citation for the Azores by Koehler (1909) and later reproduced by Grieg (1932) and Marques (1980) is likely erroneous, as to best of our knowledge no material belonging to either L. celtica or L. phalangium was ever collected in the archipelago.

In 1992, Pérès claimed to have observed a Leptometra crinoid during a dive by the bathyscaphe Archimède west of Santa Maria Island at a depth of 700 m. It is possible that Pérès might be referring to L. celtica , considering this species’ geographic and bathymetrical wide range. On the other hand, on stating a ‘crinoid of Leptometra type’, he could have been simply referring to a comatulid (an unstalked form), which in this case Pentametrocrinus atlanticus ( Perrier, 1883a) should be also considered, a species known to occur in the Azorean deep waters (see below).