Seven species of sea-skates, marine insects of the genus Halobates, are reported from Micronesia. Nymphs of nearshore species (H. mariannarum, H. flaviventris, H. nereis, H. princeps) are generally found in sheltered waters among mangrove roots and branches, whereas adults are usally found in more open water. Speciments of open-ocean species (H. micans, H. sericeus, H. germanus) may be found washed to shore after storms. Under laboratory conditions, each nymphal stadium of H. mariannarum lasts 12-14 days.
