SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bc645ad1f5be70c39ad1521526f98a630e1d55ce39286f55dddff45b640e46d' 
  AND token = 'yevIuoNiBsKgqZH0GzQ4Yn8HEsYxIomxArwcuxk/zYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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