Gregarine Parasites of Invertebrates

Gregarine parasites represent one of the most widespread and diverse groups of protozoan parasites found in nature. They belong to the phylum Apicomplexa, a large group of obligate parasitic protists that includes several medically and veterinary important organisms. Gregarines primarily infect invertebrates and are especially common in annelids and arthropods. Among insects, orthopterans such as grasshoppers and crickets and odonates such as dragonflies and damselflies are frequently reported hosts. Other insect groups that harbor gregarine infections include cockroaches (order Blattodea), mosquitoes and flies (order Diptera), and beetles (order Coleoptera). Although these parasites are widely distributed in nature, only a small proportion of invertebrate species has been systematically examined for gregarine infections. As a result, scientists believe that the actual diversity of these organisms is vastly underestimated.