Urostylididae is a family of true bugs and is considered a basal or "primitive" family within the stink-bug lineage. They are found only in Asia. Older works used the spelling Urostylidae but this clashes with the name used for a protozoan family and a spelling correction (

emendation An emendation is an alteration to a term, for a specific technical reason: * Emendation (textual), altering a word to make sense, e.g. when incomplete or assumed to have been copied incorrectly * Emendation (zoology), altering the spelling of the ...

) has been suggested that also avoids the confusion created by homonyms. The family name Urolabididae has also been used for some members in the past. This family has about 100 species, with distribution limited mainly to eastern Asia. Urostylidids are 4 to 15 mm and somewhat longer than broad with elongated legs, three tarsal segments, and a small head. The antenna has 5 segments of which the first is longer than the head. The base of the antenna has broad tubercles and has a ringed appearance. The simple eyes or ocelli, when present (''Urolabida'' lacks ocelli), are very close to each other. They show a wide separation between the hind and mid coxae on the underside. Other important family characters are the presence of a structure for stridulation, the stridulitrum on the first anal vein of the hind wing, and bristles on the claws. The female genital structure has nine gonocoxites that form a M or W-shaped sclerite. They suck plant sap. The male reproductive anatomy suggests close affinities to the

Tessaratomidae Tessaratomidae is a family of true bugs. It contains about 240 species of large bugs divided into 3 subfamilies and 56 genera. Tessaratomids resemble large stink bugs (family Pentatomidae) and are sometimes quite colorful. Most tessaratomids ar ...

subfamily

Natalicolinae Tessaratomidae is a family of true bugs. It contains about 240 species of large bugs divided into 3 subfamilies and 56 genera. Tessaratomids resemble large stink bugs (family Pentatomidae) and are sometimes quite colorful. Most tessaratomids a ...

. The

spermatheca The spermatheca (pronounced plural: spermathecae ), also called receptaculum seminis (plural: receptacula seminis), is an organ of the female reproductive tract in insects, e.g. ants, bees, some molluscs, oligochaeta worms and certain other ...

has two pump flanges in two genera which is a feature found also in the

Aradidae Aradidae is a family of flat bugs, and a member of true bugs (Heteroptera). The common name for these insects refers to their dorsoventrally flattened bodies. With few exceptions, these cryptic insects are of no economic importance. This famil ...

and

Leptopodidae Leptopodidae is a family of spiny-legged bugs in the order Hemiptera. There are about 15 genera and more than 40 described species in Leptopodidae. Genera These 15 genera belong to the family Leptopodidae: * '' Erianotoides'' J.Polhemus & D.Po ...

. Thus the phylogeny of the group is unclear but lies within the Pentatomoidea. In the past the family was divided into two subfamilies, but one group, the Saileriolinae, has since been suggested as a distinct family,

Saileriolidae Saileriolidae is a family of true bugs and is considered a basal or "primitive" family within the stink-bug lineage. They are found only in Asia. Originally included within the family Urostylididae Urostylididae is a family of true bugs and i ...

, by at least two studies. The position of Saileriolidae within the Pentatomoidea is still unclear.

References

Shield bugs Heteroptera families {{Pentatomoidea-stub