These are well known insects. Water striders are recognizable even by curious children. They are in the family Gerridae. Apparently there are about 45 North American species. I have no lists. Many of them are in the genus Gerris. All but one are fresh water insects. Halobates is the great ocean strider. These guys ride atop the water surface on the coating of fine hairs on the tarsi. If wet they sink and drown. When their streams or pools dry up they hibernate until the water returns. All the species apparently have winged and wingless forms. This one is wingless.

Found this in Yell county on a small pool. Winged form. Was somewhat smaller than the above Petit Jean species.

Camp Robinson individual which was one third the size of the top species. There were several wingless and very small striders on the pool with this one.

Sexual formation on the water surface. Seem to row comfortably along in tandem. These were in a small spring pool in Eureka Springs gardens not far from the Palace Hotel.