Atlantid Heteropods as Living Substrata for Eggs of Halobates sericeus (Heteroptera: Gerridae)

Abstract

Atlantid heteropods are collected occasionally in Hawaiian waters with yellow, narrowly elliptical objects attached to their shells. Examination of 139 of these objects from 72 atlantids showed that they consisted of an outer, clear capsule whose contents were usually yellow, although 16 were empty and four contained brown insects at an advanced stage of development. The latter were identified as preemergent nymphs of the Pacific pelagic seaskater or ocean strider, Halobates sericeus Eschscholtz. The maximal number of attached capsules was four, although most shells (79%) had one or two. Capsules averaged 0.93 mm long and 0.36 mm wide and were deposited on either the right, left, or both sides of the shell. All 72 atlantids with egg capsules were adult males. Exclusive usage of males by H sericeus is suggested to result from swarming behavior by male atlantids at the water surface. Although egg capsules were recorded from eight species of atlantids, most (86%) were on Atlanta turriculata d'Orbigny and A. fusca Souleyet, two of the most strongly pigmented species. Hypothetically, these two species would be the most visually conspicuous to H sericeus at the ocean surface.