Mutualism, commensalism, and parasitism Many species of
Periclimenes are symbiotic organisms within their reef ecosystems. The most common organisms forming symbiotic relationships with this genus are species of fish, cnidarians, echinoderms, and sponges. Some species such as
Periclimenes caraibicus have been observed to interact
parasitically with species of sponges, living within the sponge and directly eating the sponge tissue. Another species,
Periclimenes soror, is commonly found on a species of sea star known as cushion stars with no effect on the star, making it a commensalistic relationship. Anecdotal evidence suggests that
P. soror may choose a host star that matches its own coloration for camouflage. Other research demonstrated that the
Periclimenes species,
P. yucatanicus, has a
mutualistic cleaning relationship with different species of reef fish studied in the pacific.
P. yucatanicus performed a waving motion with its antennae to signal to reef fish that it is available to clean. The cleaner shrimps then ate parasitic organisms present on the reef fish species. == Characteristics ==