Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf662dcf226b121b071fb621f5bd23c6bc5b6c24bc728da086def39a3eaaa7ce' 
  AND token = 'WPhSvoEJFOpOzcdp2BtoNgLBgQ7e9z0QjlQtR4ucNkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}