Hawthorn Tree with tent web structure

Hawthorn Tree with tent web structure

Observation - Hawthorn Tree with tent web structure - UK and Ireland. Description: Bright orange caterpillars with black heads stripping the leaves of the Hawthorn Tree within a tent web structure. They have now moved on, but I'd really like to know what they are, and what they'll become when each forms into a chrysalis.

Bright orange caterpillars with black heads stripping the leaves of the Hawthorn Tree within a tent web structure. They have now moved on, but I'd really like to know what they are, and what they'll become when each forms into a chrysalis.