Common name: Jansen's wrasse

General information

Jansen's Wrasse, Thalassoma jansenii, is a vibrant and active fish species that adds both color and dynamism to a saltwater aquarium. Known for their striking coloration, which typically includes a mix of green, blue, and yellow hues, these wrasses are a favorite among aquarists. They are part of the Labridae family, which is known for the cleaning behavior some species exhibit, although this particular behavior is not prominent in Thalassoma jansenii.

Care

Jansen's Wrasse is a hardy species that requires a well-established aquarium with plenty of swimming space and rockwork for hiding. They are known to jump, so a tightly fitting lid or screen is essential to prevent escape. These wrasses are not picky eaters and will accept a variety of meaty foods, including frozen mysis shrimp, brine shrimp, and quality marine flake and pellet foods. It's important to maintain high water quality and stable parameters to keep them thriving.

Reproduction

In the wild, Thalassoma jansenii exhibits protogynous hermaphroditism, where individuals start life as females and can change to males if the dominant male is removed. This is a common trait among wrasses. In the aquarium, breeding Jansen's Wrasse is quite challenging and rarely achieved, as it requires precise conditions and a large, species-specific setup.

Habitat

Jansen's Wrasse is found in the Indo-Pacific region, from Indonesia to the Philippines, and north to southern Japan. They typically inhabit coral reefs and rocky areas where they can forage for small invertebrates. They are usually seen at depths ranging from shallow waters to about 40 meters deep.