SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33c24aad06a99117219d8548e782171ce0e804a09e0954bec7339302968bbb3c' 
  AND token = 'pjS/5OeLI3sLIadLWfv7yn4ZyZywAsBn8B/b5WbZESI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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