The Stratford on Avon Butterfly Farm has a few tropical insects which aren’t butterflies: fire ants and some stick insects. But these are housed in vivariums, alongside axolotls, toads and a few snakes.
This was on the ground of the main hothouse, possibly a tropical cockroach of some kind which had hitched along for the ride.
UPDATE: on iNaturalist, drtimk IDs this as being a giant burrowing cockroach, native to the tropical zone in Australia.