Sphaeromatidae
Guides
Cassidinidea ovalis
Cassidinidea ovalis is a species of isopod crustacean in the family Sphaeromatidae. Originally described by Thomas Say in 1818 as Naesa ovalis, this species has been reclassified into the genus Cassidinidea. The genus Cassidinidea is part of the sphaeromatid isopods, a group commonly known as pill bugs or sow bugs, though this particular genus tends toward more elongated, less strongly convex body forms than the classic 'pill bug' shape.
Exosphaeroma diminutum
Exosphaeroma diminutum is a small marine isopod in the family Sphaeromatidae, described by Menzies and Frankenberg in 1966. The species epithet 'diminutum' reflects its notably small body size relative to congeners. Like other Exosphaeroma species, it belongs to a group of crustaceans commonly known as marine pillbugs or rolly pollies, which are relatives of terrestrial isopods. The species has been recorded from Saint Thomas in the Caribbean region.
Gnorimosphaeroma
Gnorimosphaeroma is a genus of marine and estuarine isopod crustaceans in the family Sphaeromatidae. Species in this genus inhabit intertidal and shallow subtidal environments, with documented occurrences in algal beds, sedge marshes, and wood debris habitats. The genus shows behavioral adaptations for humidity detection and orientation, and includes species with annual semelparous life histories.
Sphaeroma
pillbug, roly poly, marine pillbug
Sphaeroma is a genus of aquatic isopod crustaceans in the family Sphaeromatidae. These small crustaceans are commonly known as marine pillbugs or roly polies, though they are distinct from terrestrial isopods. The genus contains multiple species distributed across marine and estuarine environments globally. Some species, such as S. terebrans, are specialized wood-borers in mangrove habitats, while others inhabit rocky intertidal zones or construct burrows in soft sediments. The genus has been subject to recent taxonomic revision, with new species described from the northeastern Pacific and elsewhere.