Cibdela janthina is a sawfly of the family Argidae. This species originates from Sumatra in South-East Asia but had also been introduced to La Réunion in 2007 for biological pest control of Rubus alceifolius, a Rosaceae species that had become an invasive species.
It has a metallic dark-blue colour, the males have a length of approx. 8 mm and the females of 9.5 mm. www.agriculture-biodiversite-oi.org
A parasitoid of C. janthina is Proterops borneoensis.Achterberg &Chenon, 2009. The first report of the biology of Proterops borneoensis Szépligeti (Hymenoptera: Braconidae: Ichneutinae), with the description of a new species from China. . - Journal of Natural History 2009 Vol. 43 No. 9/12 pp. 619–633
References
Klug, J.C.F. 1834. Übersicht der Tenthredinetae der Sammlung (des Berliner entomologischen Museums). Jahrbücher der Insektenkunde 1: 233–253.