ABSTRACT
Creeping water bugs are distinguished by their ovate, strongly dorsoven-trally flattened bodies and highly modified raptorial forelegs. Nymphs and adults spend their lives in subsurface aquatic habitats, occurring in both lotic and lentic environments where they crawl amid the substrate or cling to aquatic plants. The Naucoridae are a tropical group with a primarily southwestern distribution in North America. Only two species of Pelo-coris Stal occur east of the Mississippi River, and the genera Cryphocricos Signoret and Limnocoris Stal are each represented by a single species in Texas. Persistent records exist among the earlier literature regarding several Mexican Ambrysus species which occur in the United States. The genus Ambrysus Stal is well diversified in the western United States, and includes several Mexican species that range into southern Arizona and several others that have speciated in isolated desert hot springs.
