Batesian Mimicry: the Saddled Snake-Eel Leiuranus semicinctus

This video clip ostensibly shows a specimen of the venomous sea snake, Hydrophis melanocephalus, recorded by Diarmaid Ó Foighil on Kakeromajima (Amami Archipelago, Japan). However, appearances can be misleading, especially in cases of Batesian mimicry where harmless prey species deceive and deter predators by impersonating venomous/toxic/distasteful species. In this case, the Batesian mimic shown is a non-venomous fish - the saddled snake-eel, Leiuranus semicinctus (Ophichthidae), Japanese name: Sora-Umihebi - that was unexpectedly retrieved by Ó Foighil in a lower intertidal sediment sample. As summarized in its FishBase account*, Leiuranus semicinctus "uses its stiff pointed tail to rapidly burrow backwards into the sand when frightened", a behavior attempted towards the end of the recording.

Many thanks to Ryutaro Goto (Seto Marine Biological Laboratory, Kyoto University) for help in identifying the mimic and its model, and for organizing the field trip.

This video will be published in the Spring 2025 edition of Biodiversity Buzz, the University of Michigan EEB Museums' (Museum of Zoology and Herbarium) online newsletter.

• https://www.fishbase.se/summary/Leiuranus-semicinctus