Creseis virgula (Rang, 1828)

(Figure 5 (a))

Material examined

Ullastres 3, Llafranc (Spain), 41°53 ʹ 14.1”N, 3°12 ʹ 26.0”E, 27 February 2019, 0.5 m depth, 3 spcs, adults, L = 10 mm; Cala Sa Tuna, Begur (Spain), 41°57 ʹ 38”N, 3°13 ʹ 52”E, 9 March 2019, 0.8 m depth, 1 spc., adult, L = 10 mm; Montiel, Tamariu (Spain), 41°54 ʹ 55.9”N, 3°12 ʹ 46.3”E, 13 March 2019, 1 m depth, 20 spcs, adults, L = 5–10 mm .

External morphology

Shell narrow, elongated, conical, back end slightly curved, smooth. Parapodia transparent, large, with double-axe shape.

Ecology

Found in open waters close to the surface and around other pelagic pteropod and salp species.

Distribution

Cosmopolitan. In the Mediterranean Sea this species has been reported from the eastern and western Mediterranean, and in the Malta stretch and between Mallorca and Sicily (OBIS 2021). This is the first report of this species from the Mediterranean Spanish coast.

Remarks

Almost all records in the Mediterranean are based on shell observations or from specimens caught in plankton tows in open waters, at superficial (0–10 m) or greater depths (600–700 m; OBIS 2021). Our specimens were found from February to March along with the massive arrival of pelagic zooplankton in superficial waters. This species is very similar to C. conica Eschscholtz, 1829, so several specimens with slightly different morphologies have been collected to determine whether both species could be present. In the case of both species, this record represents the first observation of either taxon for the Catalan coast.

Genus Hyalocylis Fol, 1875