Muraena helena Mediterranean moray

Muraena helena Linnaeus, 1758

Nocturnal and territorial species, commonly lurking in holes, and writhing snakelike through crevices, under rocks or corals. Feeds on fish, crabs and squid

Synoynms:
Gymnothorax muraena Bloch & Schneider, 1801
Limamuraena guttata (Risso, 1827)
Limmamuraena guttata (Risso, 1827)
Muraena australiae Richardson, 1848
Muraena bettencourti Osório, 1911
Muraena guttata Risso, 1827
Muraena helaena Linnaeus, 1758
Muraena helena australiae Richardson, 1848
Muraena punctata Rafinesque, 1810
Muraena romana Shaw, 1803
Muraena variegata Rafinesque, 1810
Muraena vorax Ogilby, 1907
Muraenophis bettencourti (Osório, 1911)
Muraenophis fulva Risso, 1810
Muraenophis helena (Linnaeus, 1758)
Murenophis bettencourti (Osório, 1911)
Thyrsoidea atlantica Johnson, 1862

Classification: Biota > Animalia (Kingdom) > Chordata (Phylum) > Vertebrata (Subphylum) > Gnathostomata (Superclass) > Pisces (Superclass) > Actinopterygii (Class) > Anguilliformes (Order) > Muraenidae (Family) > Muraeninae (Subfamily) > Muraena (Genus) > Muraena helena (Species)

Jumping guard
A jumping guard prevents (nocturnal) fish from jumping out.
Wrasses, blennies, hawkfishs and gobies jump out of an unprotected tank in fright if their night rest is disturbed, unfortunately these jumpers are found dried up in the morning on carpets, glass edges or later behind the tank.

https://www.korallenriff.de/en/article/1925_5_Jump_Protection_Solutions_for_Fish_in_the_Aquarium__5_Net_Covers.html

A small night light also helps, as it provides the fish with a means of orientation in the dark!