SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa9cc4bfb3a81c872e5ba97c63a7e9d3a573182550bfffb5bc60b6b4b832afee' 
  AND token = '1ZfZ94yV23jD4U+/yOUWVjymNwnCqPkWoS0+GPGiIKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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