Sea slug night fever: 39 new records of elusive heterobranchs in the western Mediterranean (Mollusca: Gastropoda) Author Salvador, Xavier 0000-0003-3039-7566 Author Fernández-Vilert, Robert 0000-0002-2812-4414 Author Moles, Juan 0000-0003-4511-4055 text Journal of Natural History 2022 2022-05-18 56 5 - 8 265 310 http://dx.doi.org/10.1080/00222933.2022.2040630 journal article 10.1080/00222933.2022.2040630 38f6df24-838f-409a-90df-b56087e6a9bc 1464-5262 6758438 Limapontia capitata (O.F. Müller, 1774) ( Figure 6 (d)) Material examined Le Ponton , Étang de Thau , Sète ( France ), 43°25 ʹ 28.5”N , 3°42 ʹ E , 18 May 2017 , 1 m depth , 2 spcs, adults, L = 3 mm . External morphology Body short, thick, background colour dark brown, periocular area and tail white. Rhinophores very short, crest-like. Parapodia absent. Protuberance caused by pericardial system seen in dorsum. Ecology Specimens found in brackish waters on substrate extensively covered by the green alga Ulva lactuca Linnaeus, 1753 . Distribution Originally described in the North Sea ( England and Norway ; Muller 1773 ); also, Portugal ( Cervera et al. 2004 ); Spain : Cantabric Sea, Galicia , Levantine coast ( Templado et al. 1983 ; Cervera et al. 2004 ); Mediterranean French coast (this study). Remarks This species has been reported from eutrophic areas with variable salinity, although its presence has been attributed to having been washed there by waves ( Rudman 2021 ). It has always been found with green algae of the genera Cladophora , Ulva and Bryopsis . It can be distinguished from L. senestra ( Quatrefages, 1844 ) because it lacks long cephalic extensions, and from L. depressa Alder and Hancock, 1862 because of its particular head shape ( Gascoigne 1952 ). Genus Placida Trinchese, 1876