Adult: A black insect. The third antennal segment clearly shorter than the fourth and fifth combined. Clypeus sub-truncate. Hind tibia with white basally (basal one-third in female and basal one-quarter in male). Hind tarsus entirely black on basal segment.

Larva: All Caliroa larvae are slug-like in that the trunk is coated with a translucent mucus membrane. Consequently, the body colour of the larva is largely dependent on the colour of the gut contents. It is generally considered that C. cinxia have a more yellow tint than does annulipes, though this may be constricted to the thoracic region and, according to Schönrogge, may not be at all apparent. For more information see link below.

Detailed examination necessary. Please provide images.

Associated with Oak.

Adult flight period June to August.

Local in England.

Status in Leicestershire and Rutland not known.

https://www.sawflies.org.uk/caliroa-cinxia/