Complex sentence: The Balcones Fault Zone is a demarcation line for certain ecological systems and species distributions, e.g., the California Fan Palm ("Washingtonia filifera") is the only species of palm tree that is native to the continental United States west of the Balcones Fault.
Split into simpler sentences: The Balcones Fault Zone is a demarcation line for certain ecological systems and species distributions. For example, the California Fan Palm ("Washingtonia filifera") is the only species of palm tree that is native to the continental United States west of the Balcones Fault.