Asterina gibbosa ( Pennant, 1777 )

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 : 87

Asterina gibbosa ( Pennant, 1777)

( Fig. 17 )

Reports for the Azores:

Asterina gibbosa Forbes, 1839 — $ Barrois 1888: 70; Asteriscus sp.—? Simroth 1888: 231; Asterina gibbosa ( Pennant, 1777) — Koehler 1921b: 32–33, fig. 34, 1924: 131–133; Mortensen 1927a: 98–99, fig. 56; Tortonese 1965: 169–172, figs. 80–82; $ A.M. Clark & Downey 1992: 184–185, figs. 30a, 31a, 32a–b, pl. 41, figs. H–J; Moyse & Tyler 1995: 667, fig. 12.3; $ Morton et al. 1998: 143, fig. 7.4; Pereira 1997: 335; Micael & Costa 2010: 322; Micael et al. 2012: 6.

See: A.M. Clark & Downey (1992).

Occurrence: Mediterranean Sea and Northeast Atlantic, from Scotland to the Azores and Canaries ( Tortonese 1965).

Depth: 0–125 m ( Mortensen 1927a); AZO: low intertidal to subtidal waters ( Morton et al. 1998).

Habitat: rocky shores, under stones and crevices during the day ( Crump & Emson 1983); also found among algae, sponges and in meadows of Zostera and Posidonia ( Mortensen 1927 a, Koukouras et al. 2007).

Larval stage: lecithotrophic larva ( Haesaerts et al. 2006).

Remarks: Asterina gibbosa was reported for the first time from the archipelago by Barrois (1888), who remarked that they were quite common under boulders in the littoral of Faial and S„o Miguel islands (specimens presumably lost). Later, A.M. Clark & Downey (1992) found seven specimens belonging to this species among the zoological collection of the British Museum that reportedly came from the archipelago (no further data). Morton et al. (1998) recorded this small sea star from the low intertidal and subtidal of the Azores. Frias Martins one of the co-authors informed us that he frequently found A. gibbosa among the boulders in the shallow waters of S„o Miguel ( Fig. 17 ). More recently, Micael et al. (2012) remarked that neither Nobre (1938), Marques (1983) nor themselves found this species in the Azorean shallow waters. Micael and co-authors (2012) suggested that A. gibbosa could have disappeared locally from the Azores. Overall, neither the cryptic behaviour nor the small size of Asterina gibbosa can explain its almost complete absence in the literature (e.g., Drouët 1861; Chapman 1955; Marques 1983) and in the zoological collections (e.g., DBUA-ECH, DOP, MB–NMHN) covering more than 150 years of zoological studies on the shallow-water fauna of the archipelago. Thus, Asterina gibbosa must be considered as a rare species in the Azores, the population density of which appears to vary significantly through time.

Figures

FIGURE 17. Asterina gibbosa (Pennant, 1777) in situ (S„o Miguel Island, Azores, c. 37°44'53"N, 25°37'56"W, 1985.06, intertidal).