Giant isopod

A giant isopod is any of the almost 20 species of large isopods in the genus Bathynomus. They are abundant in the cold, deep waters of the Atlantic, Pacific, and Indian Oceans. Giant isopODs are of little interest to most commercial fisheries, but are infamous for attacking and destroying fish caught in trawls.

About Giant isopod in brief

Summary Giant isopodA giant isopod is any of the almost 20 species of large isopods in the genus Bathynomus. They are abundant in the cold, deep waters of the Atlantic, Pacific, and Indian Oceans. Giant isopODs are of little interest to most commercial fisheries, but are infamous for attacking and destroying fish caught in trawls. One of the largest species, B. giganteus, reaches a typical length between 19 and 36 cm ; an individual claimed to be 76 cm long has been reported by the popular press, but the largest confirmed was c. 50 cm. Their morphology resembles that of their terrestrial relative, the woodlouse; their bodies are dorsoventrally compressed, protected by a rigid, calcareous exoskeleton composed of overlapping segments. The abdomen has five segments called pleonites, each with a pair of biramous pleopods; these are modified into swimming legs and rami, flat respiratory structures acting as gills.

The individual species generally resemble each other, but can be separated by various morphological features, notably the number and shape of the spines on the pleotelson and the central spine on thepleotelson. They have two pairs of antennae. The uniramous thoracic legs or pereiopods are arranged in seven pairs, the first of which is modified into maxillipeds to manipulate and bring food to the four sets of jaws. The large eyes are compound with nearly 4,000 facets, sessile, and spaced far apart on the head. The largest species is found off eastern Australia, but it is possible other species are not as well-sampled.