SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7238c53ec6cf99e761bb23e6d3c913a9e29a3c0e4bcdf5dd958ca9bf42360dce' 
  AND token = 'pi2KKpDlMsQVuWQR1ioXA8kNovOuG05p1foLFU2JZZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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