SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd738cb0c88fa3b79f15f61ef1e9c25aaa6236d0c70e283931e0dc5708c5199f' 
  AND token = 'AMWFKjKarkXvR7B3HWrDI/XqF4JVJOVGd3c8WL7qWB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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