Animalia --> Arthropoda --> Crustacea --> Malacostraca
Embedded Files
Cymothoa exigua
Cymothoa exigua
Life Cycle
Life Cycle
Single host: Bony (teleost) fishes
The life cycle of C. exigua is not fully studied, but it is known to go through a free-living stage before infecting the gills of a fish host species. There, parasites mature into males, sexually reproduce, and then fully mature into females since they are a hermaphroditic species. Females migrate to the mouth, latch on to fish's tongues, and parasitize the blood supply and mucous for nutrients while the tongue wastes away. The parasite performs the same role as the tongue, eventually replacing it completely. Studies suggest females can reproduce only once in their lifetime.
Brusca, R. C.; Gilligan, M. R. (1983). "Tongue replacement in a marine fish (Lutjanus guttatus) by a parasitic isopod (Crustacea: Isopoda)" (PDF). Copeia. 3 (3): 813–816. doi:10.2307/1444352. JSTOR 1444352. Archived from the original (PDF) on 2019-07-19.
Host Information
Host Information
These parasites depend on fish hosts, whose mouths they live in and tongues they replace. One study found that host size and adult C. exigua were correlated. With a life span of around three years, C. exigua may often be outlived by hosts.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6396080/
Distribution
Distribution
The parasite is typically found in fish off the coast of California but ranges down to northern Ecuador. They are found at a wide range of depths.
C. exigua are found in fish mouths and look morphologically similar to other lice.
https://futurism.com/the-most-horrifying-parasite-cymothoa-exigua-2
Pinnotheres pisum, The Pea Crab
Pinnotheres pisum, The Pea Crab
These crustaceans are as small as a pea, hence their names. Yellow-grey, free-living males have hard exoskeletons and antennae. Females have translucent parts revealing internal organs and red inner gonads.
Life Cycle
Life Cycle
Direct, single-host: Mussels and cockles
Females live in bivalve mantle cavities, whereas males are free-living and only enter shellfish to mate. Females reproduce in the bivalve and hold the eggs until they hatch. Larvae then leave the bivalve in search of another host.
Host Information
Host Information
Infested mollusks typically host only one crab. Crabs are susceptible to predation alongside their hosts. While these parasites do not directly feed on their hosts, feeding habits of the crabs may be disadvantageous to them.
Distribution
Distribution
This crab is found in European coastal waters, typically around 4-5 meters deep.
https://www.beachexplorer.org/en/species/pinnotheres-pisum/pictures
Page updated
Report abuse