“The turquoise waters of the coral reefs are packed with species that still harbour many secrets. This is the case of Onuxodon, small fishes that live inside the shells of pearl oysters. An unusual and discreet shelter that makes any behavioural studies rather difficult. And yet, recent research conducted at the University of Liège has established that they emit sounds from dusk till dawn. A nocturnal activity that complicates observations, but has led scientists to assume that this is a call for a mate during reproduction cycles. One convenient yet surprising particularity seems to be the role of the amplifier, played by the oyster shells.”

Credit: University of Liege // (1) Loïc Kéver, Orphal Colleye, Marco Lugli, David Lecchini, Franck Lerouvreur, Anthony Herrel, Eric Parmentier, Sound production in Onuxodon fowleri (Carapidae) and its amplification by the host shell, The Company of Biologists, 2014 //

Hermit Crab with Sea Anemones on top of its shell.
Taxonomy of Hermit Crab – Kingdom: Animalia // Phylum: Arthropoda // Subphylum: Crustacea // Class: Malacostraca // Order: Decapoda // Infraorder: Anomura // Superfamily: Paguroidea
Taxonomy of Sea Anemones – Kingdom: Animalia // Phylum: Cnidaria // Class: Anthozoa // Subclass: Hexacorallia // Order: Actiniaria
Photo Credit: Adjienasir Adjierahman // PADI

Portuguese Man O’ War(s) (Phylum: Cnidaria // Class: Hydrozoa // Species: Physalia physalis) and Crab(s) (Infraorder: Brachyura) in a net filled with plastic marine debris.
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