Alex Mustard / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) hitchhiking on large t-bar nudibranch (Ceratosoma trilobatum) The shrimp gains food source and protection on the toxic seaslug. Bitung, North...

Jeff Rotman / Symbiotic emperor shrimp (Periclimenes imperator / Zenopontonia rex) living in the gills of a spanish nudibranch (Hexabranchus sanguineus) Red Sea, Egypt

Juergen Freund / Imperial / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) on an Eyed / Leopard sea cucumber (Bohadschia argus). Lembeh Strait, North Sulawesi, Indonesia

Juergen Freund / Imperial / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) on an Eyed / Leopard sea cucumber (Bohadschia argus). Lembeh Strait, North Sulawesi, Indonesia.

Juergen Freund / Imperial / Emperor shrimps (Periclimenes imperator / Zenopontonia rex) on a sea cucumber. Lembeh Strait, North Sulawesi, Indonesia.

Jeff Rotman / Emperor Shrimp (Periclimenes imperator / Zenopontonia rex) living inside gills of Spanish Dancer Nudibranch (Hexabranchus sanguineus). Egypt, Red Sea.

Alex Mustard / Emperor shrimp (Zenopontonia rex) female rides on the back of a nudirbranch (Tambja morosa), while picking food from the seabed. Anilao, Batangas marine protected area, Luzon, Philippines. Verde Islan...

Alex Mustard / Pair of Emperor shrimp (Zenopontonia rex / Periclimenes imperator) female is the larger one, hitch a ride on a large nudibranch (Tambja luteolineata) and pick food from the seabed with their claws. Bi...

David Fleetham / Imperial commensal shrimp (Periclimenes imperator / Zenopontonia rex) on Spanish dancer nudibranch (Hexabranchus sanguineus) at night. Philippines.

David Fleetham / Imperial shrimp (Periclimenes imperator / Zenopontonia rex), two on Sea cucumber (Holothuroidea). Wakaya, Fiji.

Constantinos Petrinos / Emperor shrimp (Periclimenes imperator / Zenopontonia rex) with parasitic Isopod (Bopyridae) and living commensally with Leopard Sea Cucumber (Bohadschia argus) Lembeh Strait, North Sulawesi, Indonesi...

Linda Pitkin / Emperor shrimp (Periclimenes imperator / Zenopontonia rex), commensal with Amberfish Sea cucumber (Thelenota anax) Lembeh Strait, North Sulawesi, Indonesia.