Ophiactis virens

Ophiactis virens (Sars, 1859) Reports from the Azores:

Ophiactis sp.—? $ Simroth 1888: 231; Ophiactis virens (Sars, 1859) — Koehler 1924: 194–197; Mortensen 1927a: 199; Tortonese 1965: 238–239, fig. 110; Marques 1980: 102; $ Castro & Viegas 1983: 24; $ Marques 1983: 3; Pereira 1997: 332; Jesus & Abreu 1998: 65; Micael & Costa 2010: 322; Micael et al. 2012: 3.

Type locality: Mediterranean Sea.

See: Tortonese (1965).

Occurrence: Northeast Atlantic and Mediterranean Sea; along the Western African coast to? Cape Verde (Koehler 1924, Tortonese 1965) including the archipelagos of the Azores (Marques 1983), Madeira (Jesus & Abreu 1998) and Canaries (Bacallado et al. 1985).

Depth: 0–90 m (Tortonese 1965); a littoral species in the Azores (Marques 1983).

Habitat: rocky shores, coralligenous concretions, under stones and among algae and bryozoans; can form large aggregations (Tortonese 1965).

Larval stage: unknown; also reproduces asexually through fission (Tortonese 1965).

Remarks: Koehler (1924) listed the Azores and Cape Verde in the geographical distribution of Ophiactis virens. We do not know the original observation on which he based these records. In the echinoderm fauna of the Azores, Simroth (1888) reported an Ophiactis sp., which may represent the first record of O. virens to the archipelago since is the only Ophiactis species ever reported in Azorean shallow waters. Regardless, Castro & Viegas (1983) and Marques (1983) reported having collected O. virens throughout the Azorean archipelago, thus confirming the presence of this species in the Azores. Both studies indicate that locally O. virens lives among algae, but Marques added that this species was far less abundant compared to Amphipholis squamata. We do not know where Castro & Viegas have deposited their material and we could not find Marques’ material at the Museu Bocage, Natural History Museum (Lisbon). The zoological collection of the Department of Biology of the University of the Azores houses a large number of samples derived from rocky shore algae scrapings collected over a time period of twenty years. Among those, we found numerous specimens of A. squamata, yet we have failed to find a single specimen of O. virens. The presence in the collection of numerous specimens belonging to a species does not necessarily imply a high local abundance (biased sampling), but its absence on the other hand may reflect its rare status at present. It is possible that local populations of this fissiparous six-armed species have simply declined since the publications by Castro & Viegas or Marques in the 1980s.