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Updated 8/13/2023

Phylum Arthropoda

Marine Insects

 Water Striders

Water striders inhabit the ocean surface and feed upon dead cnidarians and carrion.  Their bodies are coated with fine hairs to repel water, keeping breathable air next to the abdomen.  Hair on the leg tips utilize water tension to skim upon the water.  Two species in Hawaii. 

 

HAWAII

Halobates sericeus

Waimanalo, Oahu

PACIFIC PELAGIC WATER STRIDER

A gray-black species that lives in the open ocean and feeds upon dead cnidarians.  Rarely seen except on beaches during storms.  Leg span is about 3/4 inch.  Hawaii & the Indo-Pacific.

 

Class Pycnogonida

Sea Spiders

Spider-like animals with 4-6 pairs of segmented legs and two pairs of eyes.  They are small, cryptic, and rarely seen.  More information on Pycnogonids.

 

INDO-PACIFIC / HAWAII

Lahilahi Point, Oahu

 

Red Hill, Hawaii, 100 feet


Maui, Hawaii

Anilao, Philippines

SEA SPIDER

Seen on dive site mooring lines or under ledges exposed to strong current.  Less than 1/2 inch with legs extended.