SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99b6458c471caebb797004d1d8c54e91d265c9ff54992b0e1e4af93a834960fe' 
  AND token = 'TYiDuDFFrPi+Ez7qz2is/X0IoeJ5DP9HB0bDOxmgeGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}