''Porcellio'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

woodlice Woodlice are terrestrial isopods in the suborder Oniscidea. Their name is derived from being often found in old wood, and from louse, a parasitic insect, although woodlice are neither parasitic nor insects. Woodlice evolved from marine isopods ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Porcellionidae. These

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s are found essentially worldwide. A well-known

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

is the common rough woodlouse, ''

Porcellio scaber ''Porcellio scaber'' (otherwise known as the common rough woodlouse or simply rough woodlouse), is a species of woodlouse native to Europe but with a cosmopolitan distribution. They are often found in large numbers in most regions, with many spec ...

''. Most of the hundreds of ''Porcellio'' species were described by 1950, and many were known by the end of the 19th century already. But occasionally, new species have been found even in recent times.

Species

There are approximately 191 species in the genus ''Porcellio'' : ''Porcellio cyclocephalus'' and ''P. notatus'' are

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

species from

Baltic amber Baltic amber or succinite is amber from the Baltic region, home of its largest known deposits. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that this forested region provided the re ...

. They are placed in the present genus for lack of a better alternative, but whether this is correct is doubtful as the original descriptions are very brief and hardly diagnostic.

References

{{Authority control Porcellionidae Isopod genera Taxa named by Pierre André Latreille