Doto pygmaea Bergh, 1871

Salvador, Xavier, Fernández-Vilert, Robert & Moles, Juan, 2022, Sea slug night fever: 39 new records of elusive heterobranchs in the western Mediterranean (Mollusca: Gastropoda), Journal of Natural History 56 (5 - 8), pp. 265-310 : 280-282

Doto pygmaea Bergh, 1871

( Figure 3 (h))

Material examined

Cala d’Aiguablava , Begur ( Spain), 41°56 ʹ 13.4”N, 3°13 ʹ 08.6”E, 22 June 2018, 0 m depth, 6 spcs, juveniles and adults, L = 2–5 mm; Cala Maset caves, Sant Feliu de Guíxols ( Spain), 41°47 ʹ 10.5”N, 3°2 ʹ 44.6”E, 11 February 2020, 0.1 m depth, 7 spcs, adults and egg masses, L = 5–10 mm .

External morphology

Body elongate, narrow, background colour white with black patches to completely black. Rhinophores elongate, transluscent white. Cerata displayed in a sinuous ‘S’ fashion with white tubercles only on the external part, the inner part being almost smooth.

Ecology

Specimens found on floating debris. The specimens from Aiguablava were living on plastic debris eating hydrozoan colonies, probably of the genus Obelia . The specimens of Cala Maset were living on floating wood. Slugs mated and laid egg masses while eating hydrozoans of the genus Tubularia . Egg masses are shaped like a winding cord forming an ‘S’; egg colour is yellowish.

Distribution

Italy ( Schmekel and Portmann 1982); Spain: Canary Islands ( Cervera et al. 2004), Spanish Levantine coast ( Cervera et al. 2004), Catalonia (this study).

Remarks

This species can be differentiated from other Doto species by having a black body with very elongated rhinophores, a smooth edge on the rhinophoral sheath, and ‘S’-shaped cerata, the inner part being almost smooth and the external with tubercles aligned longitudinally ( Ortea et al. 1997).

Family PHYLLIROEIDAE

Genus Phylliroe Péron and Lesueur, 1810

Figures

Figure 3. Photographs of live Nudibranchia species: (a) Palio nothus and its egg mass. (b) The alien Polycera hedgpethi. (c) Polycerella emertoni and egg mass on Amathia verticillata. (d) Thecacera pennigera on top of the bryozoan Bugula sp. (e) Two specimens of Anteaeolidiella lurana and their egg masses. (f) Doto cervicenigra. (g) Doto fragilis (photo credit: Oriol Planas). (h) Doto pygmaea.