SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '397e56481e6457aad794fb6032032216ea8f53da59b0802e617dda9145468897' 
  AND token = 'kCt9y0qm458WcVcwvFU5V83884LijBgxwZRoZ9ZjBFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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