Guide books, scientific papers, web sites are sources of data (observations, descriptions…) that can be useful to understand what’s surround you while snorkelling … I used more particularly the following references.
Guide books (in French)
Augier Henry, 2007. Guide des fonds marins de Méditerranée. Les guides du naturaliste. Delachaux et Niestlé, 456p.
Simeonidis, Noelle & Dinos. La vie dans les mers grecques et la Méditerranée. Mediterraneo Editions, 245p. ISBN : 978-960-6848-26-1.
Weinberg Steven, 1998. La Méditerranée. Nathan Nature, 351p. ISBN 2.09.260663.8
To go a little further …
Little C., Gray A. Williams, C.D. Trowbridge. 2009. The Biology of Rocky Shores (Biology of Habitats). Oxford Univ. Press, USA, 356p. ISBN: 978-0-19-856491-1.
Kaiser, M.J., M.J. Attrill, S. Jennings, D.N. Thomas, D.K.A. Barnes, A.S. Brierley, J.G. Hiddink, H. Kaartokallio, N.V.C. Polunin, D.G. Raffaelli, 2011. Marine Ecology – Processes, Systems, and Impacts. 2nd edition. Oxford University Press, 501p. ISBN: 978-0-19-922702-0
Ruppert E.E., R.S. Fox, R.D. Barnes. 2004. Invertebrate Zoology – A functional evolutionary approach. 7th ed. Thomson-Brooks/Cole, 963p. + Index 1-26
Additional references – Jellyfish
İsinibilir, M. Yuksel, E., & Dalyan, C. (2021). First record of Cotylorhiza tuberculata (Macri, 1778) from the sea of Marmara. Aquatic and Engineering, 36(1), 38-41.
Kikinger, R. (1992). Cotylorhiza tuberculata (Cnidaria: Scyphozoa) – Life History of a Stationary Population. Mar. Ecol. 13 (4), p.333 – 362.
Lilley, Martin K. S., Martina Ferraris, Amanda Elineau, Léo Berline, Perrine Cuvilliers, Laurent, Gilletta, Alain Thiéry, Gabriel Gorsky, and Fabien Lombard. 2014. “Culture and Growth of the Jellyfish Pelagia noctiluca in the Laboratory.” Marine Ecology Progress Series 510: 265–73
Prieto L, Astorga D, Navarro G, Ruiz J (2010) Environmental Control of Phase Transition and Polyp Survival of a Massive-Outbreaker Jellyfish. PLoSONE 5(11): e13793. doi:10.1371/journal.pone.0013793
Web sites (in French)
https://doris.ffessm.fr
https://www.fishipedia.fr/fr/poissons/native_regions/mer-mediterranee