Trinchesia cuanensis Korshunova, Picton, Furfaro, Mariottini, Pontes, Prkić,, 2019

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 : 287-288

Trinchesia cuanensis Korshunova, Picton, Furfaro, Mariottini, Pontes, Prkić,

Fletcher, Malmberg, Lundin and Martynov, 2019

( Figure 4 (h))

Material examined

Punta del Romaní, L’Escala ( Spain), 42°6 ʹ 54”N, 3°10 ʹ 9”E, 10 February 2014, 7 m depth, 1 spc., juvenile, L = 3 mm; 14 February 2015, 14 m depth, 1 spc., adult, L = 10 mm; Le Ponton, Étang de Thau, Sète ( France), 43°25 ʹ 28.5”N, 3°42 ʹ E, 14 April 2018, 1 m depth, 3 spc., adults, L = 7–20 mm; Cala Maset caves, Sant Feliu de Guíxols ( Spain), 41° 47 ʹ 10”N, 3°2 ʹ 44”E, 15 April 2018, 0.6 m depth, 15 spcs, juveniles, adults and egg masses, L = 4–15 mm; 6 June 2018, 0.6 m depth, 20 spcs, adults and egg masses, L = 10–15 mm; 11 March 2020, 0.5 m depth, 12 spcs, adults and mating, L = 7– 15 mm; Tamariu beach ( Spain), 41°55 ʹ 0.5”N, 3°12 ʹ 27.1”E, 11 February 2019, 2 m depth, 4 spcs, adults, L = 6–10 mm.

External morphology

Body elongate, narrow, background colour white or light yellow. Rhinophores and oral tentacles smooth, more intensely white than the body. Red or orange mark between eyes and on central dorsum. Cerata globular, displaying a bright yellow-blue-yellow colouration.

Ecology

Specimens found mating and laying the eggs on the hydrozoans Sertularella mediterranea Hartlaub, 1901 and Sertularella polyzonias (Linnaeus, 1758) inside superficial caves.

Distribution

North-east Atlantic ( Korshunova et al. 2019); Adriatic Sea (Ballesteros et al. 2012–2021); Mediterranean French coast (this study); Spain: Catalonia (this study).

Remarks

This species was recently described and observed in the North Atlantic and Mediterranean Sea ( Korshunova et al. 2019). It is different from similar Trinchesia species by having one light or pale red marking between the eyes and in the middle part of the back. This species likely has a shorter life cycle than T. morrowae ( Korshunova et al. 2019) , since it has only been observed in the winter and spring months, whereas T. morrowae is observed yearround. Trinchesia caerulea ( Montagu, 1804) has been found only during spring and autumn and is usually found in deeper waters than T. cuanensis (X. Salvador pers. obs.).

Figures

Figure 4. Photographs of live Nudibranchia species: (a) The pelagic Phylliroe cf. bucephala. (b) Amphorina andra surrounded by hydrozoans of the genus Sertularella. (c) Eubranchus prietoi on the hydrozoan Kirchenpaueria halecioides. (d) The alien Godiva quadricolor. (e) Three specimens of Piseinotecus soussi and their egg masses. (f) Piseinotecus sphaeriferus on top of the hydrozoan Obelia sp. (g) Tenellia adspersa. (h) Trinchesia cuanensis on top of the hydrozoan Sertularella sp.