Hemiliostraca clandestina (Mifsud & Ovalis, 2019) Albano & Steger & Bakker & Bogi & Bošnjak & Guy-Haim & Huseyinoglu & LaFollette & Lubinevsky & Mulas & Stockinger & Azzarone & Sabelli, 2021

Albano, Paolo G., Steger, Jan, Bakker, Piet A. J., Bogi, Cesare, Bosnjak, Marija, Guy-Haim, Tamar, Huseyinoglu, Mehmet Fatih, LaFollette, Patrick I., Lubinevsky, Hadas, Mulas, Martina, Stockinger, Martina, Azzarone, Michele & Sabelli, Bruno, 2021, Numerous new records of tropical non-indigenous species in the Eastern Mediterranean highlight the challenges of their recognition and identification, ZooKeys 1010, pp. 1-95 : 1

Hemiliostraca clandestina (Mifsud & Ovalis, 2019) comb. nov. Figure 16A-C

New records.

Israel • 1 spcm; Ashqelon; 31.6868°N, 34.5516°E; depth 12 m; 30 Apr. 2018; offshore rocky reef; suction sampler; HELM project (sample S12_1F) • 38 spcms; Ashqelon; 31.6891°N, 34.5257°E; depth 25 m; 2 May 2018; offshore rocky reef; suction sampler; HELM project (samples S16_1F, S16_2F, S16_2M); size: H 2.7 mm, L 0.9 mm (illustrated shell) • 16 spcms; same collecting data as for preceding; depth 28 m; 31 Oct. 2018; HELM project (samples S59_1F, S59_2F, S59_3F) • 1 spcm; west of Rosh HaNikra Islands; 33.0725°N, 35.0923°E; depth 20 m; 1 May 2018; rocky substrate; suction sampler; HELM project (sample S13_3F).

Remarks.

Sticteulima clandestina and S. athenamariae , both Mifsud & Ovalis, 2019, were described on specimens collected in Turkey ( Mifsud and Ovalis 2019). However, both belong to species present in the Red Sea and were illustrated by Blatterer (2019) for the Gulf of Aqaba on plate 131, fig. 8a-d and plate 131, fig. 9a-h, respectively. Sticteulima clandestina appears rather variable but our specimens clearly match Mifsud and Ovalis (2019: fig. 1B). Both S. clandestina and S. athenamariae look closely related to Hemiliostraca and thus we propose the new combinations Hemiliostraca clandestina and Hemiliostraca athenamariae . This is the first record of H. clandestina in Israel, but the species has been recorded for Lebanon based on empty shells collected in 1999 ( Crocetta et al. 2020). Consequently, it is likely present here since at least 1999, with a ~ 20 year time-lag in first detection as quantified also for other non-indigenous species in the Mediterranean Sea ( Crooks 2005; Albano et al. 2018). This is also the first record of living individuals from the Mediterranean Sea. Despite the relatively large number of living individuals, we did not find any attached to an echinoderm host; this is consistent with the fact that some eulimids actively leave the host if disturbed ( Warén 1984).

Figures

Figure 16. Hemiliostraca clandestina (Mifsud & Ovalis, 2019), and comparison between Vitreolina philippi (de Rayneval & Ponzi, 1854) and Vitreolina sp. A-C Hemiliostraca clandestina, Ashqelon, Israel, HELM project (sample S 16 _ 1 F): front (A), side (B) and back (C) views. D Vitreolina philippi (de Rayneval & Ponzi, 1854), Plakias, Crete, Greece (sample Rh. 05 _ 5 M): front view. E, F Vitreolina cf. philippi, Ashqelon, Israel, HELM project (S 16 _ 2 F): front (E) and side (F) views. Scale bars: 0.5 mm.