Abstract
Invasive plant species have negative ecological impacts such as displacing indigenous plants and invertebrates. These invasive plant species affect biodiversity by impacting indigenous vegetation and the food webs associated with this vegetation. We assessed how Lantana camara affects indigenous plant species richness and invertebrates and their feeding guilds in riparian habitats inside the Groenkloof Nature Reserve in South Africa. We showed: (1) A lower abundance and morphospecies richness of invertebrates as well as lower numbers of plant species in lantana-invaded habitat as compared to indigenous bush and grass-dominated habitats. (2) A Negative association between plant species richness and L. camara above ground mass and shoot density, but no association was found between plant species richness and the size of L. camara invaded areas. This finding suggests a link between the reduction in overall invertebrate abundance and morphospecies richness and the replacement of native plant species by invasive lantana. (3). This increased biomass in natural vegetation was even more evident for detrivores as compared to other feeding guilds. Extensive invasion by L. camara is affecting the quality of riparian ecosystems especially for invertebrates that rely on decaying plants and animals as food and this will affect overall biodiversity.