Sea-urchin Snapping Shrimp

The Sea-urchin Snapping Shrimp, also known as the Striped Upside-Down Shrimp (Arete indicus), is a fascinating marine creature living in close association with sea urchins, particularly the Echinometra mathaei species. These tiny shrimps are part of the Alpheidae family and are known for their vibrant dark red bodies adorned with bluish stripes, which makes them appealing subjects for underwater macro photography. However, spotting them can be challenging for those not trained to look for such small, intricate details.

Inhabiting tropical waters, these shrimps are benthic, meaning they dwell at the bottom of the ocean, typically in shallow waters at depths ranging from 1 to 5 meters (about 3 to 16 feet). They are quite small, measuring only about 0.8 centimeters (approximately 0.3 inches) in length.

The Sea-urchin Snapping Shrimp is found in the Indo-Pacific region, where it exhibits intriguing behaviors typical of the Decapoda order. These shrimps are mostly gonochoric, meaning individuals are distinctly male or female, and partake in a courtship ritual involving olfactory and tactile cues before mating. Reproduction usually involves indirect sperm transfer, adding an extra layer of complexity to their fascinating lifecycle.