SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03b4c9c0a81def411bc3ee3ba0821b9720f6522f813a9e43bb334533fbe0e15c' 
  AND token = 'VU3tRYud0oPh3aq5c3KNKGQSfS1RQ9R6uSTrjo3ObN8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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