Small Red Damselfly (Ceriagrion tenellum) has been recorded in the past in Monmouthshire but there are no recent confirmed records.
Previous records of Small Red Damselfly have mostly been in the northwest uplands, which appears to hold suitable habitat for the species, and where a number of other species are found which co-occur with the species at sites elsewhere in its British range.
The species has been reported elsewhere in Monmouthshire but in unsuitable habitat and these records are regarded as misidentifications for the common and widespread Large Red Damselfly (Pyrrhosoma nymphula). Further investigation into the past status of this species is needed to establish whether it has ever reliably occurred in Monmouthshire or if records from the northwest are also misidentifications.
Elsewhere in Wales, there are populations in several western counties, from Pembrokeshire and Carmarthenshire north to Anglesey, and in England it is found in several southern and eastern counties from Cornwall to Norfolk. On the continent, it is found in Iberia, France and Italy, northeast to northern Germany and southeast to Albania, and there are also populations in north Africa.