SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e33909a36af1ac095aadb84fa0a982614177ecd121cf91f4f01eef4346cd94b5' 
  AND token = '7hbSKh0QzHfkzQEEgGMlvA7WijCVA7POeKHdMK1W6Lo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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