Complex sentence: The Juan de Nova Island, in the Mozambique Channel, is named after him, as well as the Farquhar atoll was, for a long time, known as the João da Nova islands.
Split into simpler sentences: The Juan de Nova Island, in the Mozambique Channel, is named after him. The Farquhar atoll (in the Seychelles) was, for a long time, known as the João da Nova islands.