Procaris hawaiana facts for kids

Procaris hawaiana is a special kind of shrimp that belongs to the family Procarididae. You can find this shrimp in the waters around Maui, Hawaii. It looks a lot like another shrimp called Procaris ascensionis, which lives far away on Ascension Island.

There are a few small differences between these two shrimp. For example, P. hawaiana has a slightly firmer outer skin and a longer snout (called a rostrum). These tiny details help scientists tell them apart!

Meet the Hawaiian Cave Shrimp

What Does Procaris hawaiana Look Like?

This shrimp has a short, pointed snout (rostrum) that extends just past its eyes. Its main body shell, called the carapace, is smooth and doesn't have any sharp spines. It has a faint line on its neck area.

The shrimp's body is made up of smooth segments, like rings. The first segment has large, rounded side plates. The third segment is special because its back part extends like a hood over the fourth segment. The sixth segment is about one and a half times longer than the fifth.

Eyes and Antennae

The Procaris hawaiana has wide eyes, but they don't have clear parts for seeing, like our eyes do. Instead, they have a small, cone-shaped bump that points forward.

Its tail, called the telson, is longer than its last body segment. It's shaped like a triangle and has two pairs of small spines on its top. The very end of the tail has four pairs of spines.

The shrimp also has long, thin feelers called antennae. These help it sense its surroundings.

Inside the Mouth and Legs

The shrimp's mouthparts are quite interesting. It has a single grinding tooth (a molar process) and a three-part sensing tool called a palp. It also has special mouth legs, called maxillipeds, which help it eat.

None of the shrimp's walking legs have a claw, unlike many other shrimp. Instead, they have a large, movable spine on one part of the leg.

Size and Color of Procaris hawaiana

These shrimp are quite small. Their main body shell (carapace) can be about 4 to 8 millimeters long. Their total body length, from head to tail, can range from about 10 to 30 millimeters (which is about 0.4 to 1.2 inches).

Procaris hawaiana usually has a pale, slightly purplish-pink color. Its main body shell might look yellow or whitish because you can see its internal organs through its skin. It often has a darker red spot behind its snout and another one near the middle of its back.

Its belly is usually pink, and its legs are pale pink or clear. Sometimes, different shrimp might show slightly different color patterns.

Where Does Procaris hawaiana Live?

You can find Procaris hawaiana in places like Cape Kinau and Hawaii Island. They live in small, special pools called anchialine pools. These pools are found near the coast but are not directly connected to the ocean. They often have a mix of fresh and saltwater.

In these pools, Procaris hawaiana sometimes shares its home with other shrimp species, like those from the Calliasmata family.

How Does Procaris hawaiana Behave?

This shrimp is known for how it swims. It extends its legs out like a fan and moves them together in a smooth way, staying flat below its body. It often swims close to the bottom (the lava rock), but sometimes you might see it swimming in the middle of the water or even upside down along the surface.

• Procaris hawaiana at the Encyclopedia of Life