A large aggregation of Purple Heart Urchins (Astropyga radiata) marches along in preparation for a seasonal breeding event. There will be a fusion of sperm and eggs after both have been released into the water column.

A single Purple Heart Urchin (Astropyga radiata) displays its needles and its mysterious sack. When the urchin's needles puncture the skin, throbbing pain and swelling occur and sleepless nights ensue.

A Cuttlefish (Sepai latimanus) raises its tentacles in a defensive threat display. Cuttlefish have bony chambers that fill with gas enabling them to gracefully hover, rise and fall.

Seen from above the reef, the slender branches of this Red Sea Whip (Elllisela sp.) spread out fan-like to capture nutrients and display their beauty from a different perspective.

The Thorny Seahorse (Hippocampus histrix) is rarely encountered. It uses its prehensile tail to cling to branches of floating algae. The males incubate the eggs of the female that have been embedded in their abdominal brood pouch.

A single, golden Crinoid (Crinoidea sp.) spreads its feather-like arms to capture nutrients from the current. Crinoids are cousins of sea stars (starfish).

A Giant Frogfish (Antennarius commerson) occupies one fold and scans the water for prey.

A large Brain Coral (Platygyra lamellina) sports a bouquet of sea squirts and crinoids.

The largest bi-valve in the world, the Giant Clam (Tridacna gigas) can reach 5' in length. This one sits anchored to a Brain Coral (Platygyra lamellina) while a school of fish swim down the reef in the background.

The White-Mouth Moray Eel (Gymnothorax meleagris) is a known predator of small fishes who associate its white spots on a dark background with danger. The white spots will elongate with age.

A Crinoid (Oxycomanthus bennetti) hangs onto a sponge with its cirri. This species likes currents and is commonly found in passes and other areas with good water flow.

The Porcelain Anemone Crab (Neopetrolisthes ohshimai) sits on the edge of a Sticky Anemone (Stichodactyla mertensii). Its 2 claws, with their net-like appendages, are alternately flung in and out to capture plankton.

A Two-Stripe Clingfish (Discotrema lineata) clings to its host crinoid. Its tapered body ends in a tail that mimics the arms of its host, and its pelvic fins are modified into suction cups that help it to stay put.

A flamboyantly colored Nudibranch (Flabellina exoptata) wraps itself around a piece of brightly colored hard coral. Its elongated and tapering body has rows of white-tipped cerata on its dorsal surface.

A pair of Western Clownfish (Amphiprion ocellaris) lives in harmony with an unnaturally white Magnificent Sea Anemone (Hecteractis magnifica) that has lost its color and symbiotic internal algae (zooxangthellae) in a tropical warming event.

A Soft Coral (Dendronepthya sp.) that is usually seen upright is bent into a highly unusual shape as the result of an extremely strong current.

A shy species, the Yellow-Headed Moray Eel (Gymnothorax rueppelliae) gracefully curves its body around hard coral on the reef.

These black Whip Corals (Cirripathes sp.) are long, slender and whip-like. Frequently encountered on deeper reefs, they provide a stark, simple beauty in contrast to other more brilliant, ornate forms of corals.

A Broad Club Cuttlefish (Sepia latimanus) poses in front of a reef. Cuttlefish are highly advanced invertebrates. They possess a huge array of hues and patterns enabling them to provide a rich repertoire of signals for defense, hunting and reproduction.

A Soft Coral Tree (Siphonogorgia sp.), light in color and delicate in appearance, shares the reef slope with a school of Blue-Dash Fusiliers (Ptreoceasio tile) and colorful sponges.

A floral-like sculpture of Hydroids (Aglaophenia curressina), Sea Squirts (Polycarpa aurata), Mushroom Leather Coral (Sarcophyton sp.), and various sponges can be observed from above a rocky outcropping.

This Dwarf Pipefish (Acentronura tentaculata) is approximately 1/2" long and incredibly narrow. Because of its size and its camouflage, it takes an incredibly trained or eager eye to spot it.

This Red-Horned Nudibranch (Hypselodoris sp.) vacuums algae as its food supply as it travels along unconcernedly.

Viewing a Gorgonian Fan (Subergorgia moltis) from the top down provides a very different perspective. These fans can reach a height of 7' to 10'.

A Flame File Shell (Limaria sp.) is a strikingly beautiful scallop, capable of swimming, and cements itself under ledges or into cracks in the reef. Its flaming, cherry-red color is caused by the amount of hemoglobin in its blood.

These three unusually bright red Crinoids (Crinoidea sp.) adorn the wall on a reef much like signposts on a water highway.

The Sea Squirt (Herdmania momus) has two siphons for filtering nutrients. This intake siphon filters by way of these distinctive, delicate cilia.

Yellow Cup Corals (Tubastraea sp.) are flamboyantly colored. Their large, sunflower-like polyps emerge at dusk to feed. They are often found on vertical walls.

A large palette of colors can be seen in this reef scene of hard and soft corals.

The Broad Club Cuttlefish (Sepia latimanus) utilizes specialized color cells controlled by its nervous system for camouflage in order to escape pursuers and to mesmerize prey before attacking.

A magnificent Hard Coral (Scleractinia sp.) large in size, and splendid in form, graces a wall.

Sponges (Phylum Porifera) appeared on earth over half a billion years ago. These Tube Sponges (Cribrochalina olemda) presented a perfect opportunity to record them as an underwater sculpture.

A pastel pink Gorgonian Fan (Acabaria sp.) on a wall with a diver in the background.

An Elegant Squat Lobster (Lauriea siagiani) with its numerous sharp spines and its egg pouch finds sanctuary in a crevice of a Barrel Sponge (Xestospongia sp.).

The Hawksbill Turtle (Eretmochelys imbricata) is a critically endangered sea turtle. This one was found taking a break under a ledge covered with colorful sponges and corals.

A diver caught in the rays of the sun evokes a feeling of majesty as he begins his descent.