Sexy Shrimp

Thor amboinensis, commonly known as the Squat Anemone Shrimp or Sexy Shrimp, is a small shrimp species widely distributed in tropical and subtropical regions of the Indo-Pacific and Atlantic Oceans. This shrimp is usually found within shallow reef ecosystems, at depths ranging from 1 to 60 meters (3.3 - 197 feet), where it forms symbiotic relationships with marine invertebrates like corals and sea anemones.

Reaching a typical length of 1.3 to 1.6 centimeters (about 0.5 to 0.6 inches), the shrimp is notable for its olive-brown coloration with white patches outlined by thin blue lines. Its abdomen is often held in a distinctive upward curve, with its tail fan above its head.

Thor amboinensis, despite its name hinting at origins from Ambon Island in 🇮🇩 Indonesia, has a pantropical distribution including areas like the 🌊 Red Sea, 🌊 Indian Ocean, 🌊 Pacific Ocean, 🌊 Caribbean Sea, 🌊 Gulf of Mexico, Madeira, and the Canary Islands. In places like 🇧🇲 Bermuda, this shrimp frequently associates with sea anemones such as the carpet anemone, stinging anemone, and adhesive anemone. These shrimps live among the tentacles of their hosts, where they feed on tentacle tissue and trapped planktonic particles, often residing with multiple individuals on a single host.

Female shrimps carry fertilized eggs beneath their abdomens until they hatch. The larvae, called zoea, go through several developmental stages, using chemical and visual cues to locate potential host anemones. These larvae are adaptable generalists, capable of associating with various anemone species, although they tend to prefer the anemone species their mother was collected from.

In home aquariums, Thor amboinensis is popular due to its attractive appearance and small size, making it ideal for nano reef tanks. They thrive in groups of three or more and prefer to associate with any available anemones or compatible coral species. In captivity, they are scavengers, feeding on meaty remnants such as mysis shrimp, clam, and fish foods. The presence of a host cnidarian may encourage them to feed on the host's mucus as well.

As members of the order Decapoda, these shrimps are mostly gonochoric, meaning individuals are either male or female. Mating involves a precopulatory courtship ritual using olfactory and tactile cues, typically followed by indirect sperm transfer.