Pawsonia saxicola? ( Brady & Robertson, 1871 )

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 : 136-137

Pawsonia saxicola? ( Brady & Robertson, 1871)

Reports for the Azores:

Cucumaria montagui ( Fleming, 1828) — $ Marenzeller 1892: 65, 1893: 15–17; Perrier 1902: 275; Koehler 1921b: 150–152, fig. 101;

Cucumaria saxicola Brady & Robertson, 1871 — Mortensen 1927a: 401–402, fig. 240; Tortonese 1965: 75–76;

Pawsonia saxicola ( Brady & Robertson, 1871) — Pérez-Ruzafa et al. 1992a: 167; Pereira 1997: 333; García-Diez et al. 2005: 51; Micael & Costa 2010: 323; Micael et al. 2012: 4.

Type locality: Ireland .

See: Brady & Robertson (1871: 690–691, pl. 71, figs. 1–4, as Cucumaria saxicola ); McKenzie (1991: 156–157, figs. 8e–i).

Occurrence: Mediterranean Sea and northeast Atlantic, from the British Islands ( McKenzie 1991) to the Canaries ( Hernández et al. 2013) and? Azores.

Depth: 0–50 m ( McKenzie 1991);? AZO: 130 m ( Marenzeller 1892).

Habitat: in rock crevices, under stones or among algae ( Picton 1993).

Larval stage: lecithotrophic ( Newth 1916).

Remarks: during the late 19 and early 20 th centuries, a serious debate took place to decide if Cucumaria montagui was a valid species or a junior synonym of Pawsonia saxicola or Aslia lefevrei (e.g., Marenzeller 1893; Norman 1905; Orton 1914). Cucumaria montagui was reported from the Azores by Marenzeller (1892, 1893) based on the material collected by Hirondelle on a station located in the channel between Pico and Faial islands, at a depth of 130 m. Marenzeller proved later to be incorrect on the use of the name ‘montagui’ for this cucumarid, and the report from the Azores was accepted under the synonymy of P. saxicola in later works. In his review, McKenzie (1991) considered that the depth of the Azorean record was far too deep for this shallow-water species and suggested that it could be a result of a misidentification. However, it is hard to believe that Marenzeller, who was very familiar with the forms we now know as P. saxicola could have misidentified the species. Among the fauna collected by Hirondelle at this station, we find a collection of animals belonging to the shallow-water realm such as Thyone inermis (see below), a species with a depth range very similar to P. saxicola . This suggests that the depth at which these holothurians were collected could have been much shallower than the reported 130 m. Regardless, this species was never recollected in the archipelago and thus the inclusion of P. saxicola in the Azorean fauna should be considered with caution.