Clasifică nemathelminthes dan annelida
One species known from Japan is also found in North Americawhere several more species are found.
Sclerosomatidae are divided into several subfamilies, with Gagrellinae found in the Indo-Malayan and neotropical region, Gyinae at high elevations in the CaucasusAlps and NepalLeiobuninae in the holarctic region down to Costa Ricaand Sclerosomatinae only in the Palearctic. In the Phalangiidae, the Phalangiinae are most diverse in the Mediterranean, with several endemic genera in nearby coastal Africa.
Although there are several Phalangiinae in the Nearctic, they are all introduced.
Opilioninae are mostly palearctic, with a few species found in Southeast Asia. Oligolophinae are holarctic, with most species found in Europe.
Platybuninae are also found from Europe to the Caucasus, with one find from Sumatra. Systematics Although the two recognized superfamilies Caddoidea and Phalangoidea are probably monophyletic, the limits of families and subfamilies are uncertain in many cases, and are in urgent need of further study.