Ranatra is a genus of slender predatory insects of the family Nepidae, known as water scorpions or water stick-insects. There are around 100 Ranatra species found in freshwater habitats around the world, both in warm and temperate regions, with the highest diversity in South America and Asia. Fewer are found elsewhere, but include several African, some in North America, three from Australia and three from the Palearctic, notably the relatively well-known European R. linearis. Since Ranatra belongs to the family Nepidae which in turn belongs to the order Hemiptera, ranatrids are considered "true bugs".
Ocyptamus is a large and diverse genus of over 200 species of hoverfly mostly found in the Neotropical region. It is likely that many of these species will be discovered to be synonyms though many others await description.
Gerris is a bug genus in the family Gerridae.
Aquarius is a genus of water striders found predominantly in the northern hemisphere. Formerly a subgenus, Aquarius was elevated to generic rank in 1990 on the basis of phylogenetic analysis. These are among the world's largest water striders, with females averaging 12–17 mm (0.47–0.67 in) long and males roughly 10–30% smaller, depending on the exact species. An outlier is A. elongatus where both sexes typically are about 24 mm (0.94 in), roughly the same as certain Cylindrostethus, and second only to Gigantometra gigas.
Neogerris is a genus of water striders in the family Gerridae. There are about 13 described species in Neogerris.
Teleonemia is a genus of lace bugs in the family Tingidae. There are at least 80 described species in Teleonemia.
Mesovelia is a genus of water treaders in the family Mesoveliidae. There are more than 30 described species in Mesovelia.
Catorhintha is a genus of leaf-footed bugs in the family Coreidae. There are more than 30 described species in Catorhintha.
Pnirontis is a genus of assassin bugs in the family Reduviidae. There are more than 30 described species in Pnirontis.
Limnoporus is a genus of water striders in the family Gerridae. There are six extant described species in Limnoporus.
Rheumatobates is a genus of water striders in the family Gerridae. There are more than 30 described species in Rheumatobates.
Gargaphia is a genus of lace bugs in the family Tingidae. There are more than 70 described species in Gargaphia.
Euthochtha is a genus of leaf-footed bugs in the family Coreidae, containing only one described species, E. galeator. It is sometimes referred to by the common name "helmeted squash bug".
Merragata is a genus of velvet water bugs in the family Hebridae. There are about seven described species in Merragata.
Grypus is a genus of marsh weevils in the beetle family Brachyceridae. There are about 10 described species in Grypus.
Coelopa is a genus of kelp flies in the family Coelopidae. There are about 14 described species in Coelopa.
