Alternanthera philoxeroides, commonly referred to as alligator weed, is a native species to the temperate regions of South America. Argentina alone, hosts around 27 species that fall within the range of the genus Alternanthera.
Alternanthera philoxeroides can thrive in both dry and aquatic environments and is characterized by whitish, papery flowers along its short stalks, irregular, or sprawling hollow stems, and simple and opposite leave pattern sprouting from its nodes. The species is dioecious. It is also considered a herbaceous plant due to its short-lived shoot system. Its geographic range once used to cover only the Parana River region of South America, but it has since expanded to cover over 30 countries, such as the United States, New Zealand, China and many more. This invasive species is believed to have been accidentally introduced to these non-native regions through sediments trapped/attached to tanks and cargo of ships travelling from South America to these various areas.