A widespread species, found mainly around the warmer Mediterranean Countries of Europe and into North Africa; reaching over to the far eastern countries of Iran and neighbouring countries.
R. oculatum, is a large solitary Potter wasp, having an important part in the biological control of many lepidoptera (Geometridae, Tortricidae) Caterpillars, also Coleoptera, (Curculionidae, Chrysomelidae) Larvae of Beetles, which are preyed upon, to provide provisions for their young larvae.
The prey is paralised, then taken to her nesting site, usually the nest is found in decaying wooden holes and crevices, sealed with mud.
This wasp is beneficial to commercial growers and gardeners, as like most wasps, they are a natural biocontrol of garden pests, such as beetle larvae, flies and a variety of caterpillar pests.
Habitat: Many various locations, from dry scrub areas to rich meadows, grasslands, orchards, crop fields, urban gardens and wetlands, wherever their prey and nectar plants are to be found.