A Yellow Mellow Interesting Fellow
Epibulus insidator is interesting in that it has only 3 common names in English: Slingjaw Wrasse, Jawslinger Wrasse, and Telescope fish. Conversely, it has over three dozen common names in the Philippines alone and over 60 documented common names world wide! Their English common names are derived from a very interesting feeding behavior where the jaw of the fish extends out (nearly the entire length of the fish) to engulf their prey. For those of you who can't have one, some really cool videos are out there on Youtube for you to see it. There are multiple reports of Slingjaw Wrasses hunting in concert with other species of fish! There are even images and videos of them swimming in tandem with Trumpet fish while hunting along coral heads!
They are a common fish throughout the tropical Indian and Pacific Oceans, including the Red Sea. Adults generally live singly and can be found along steep drop offs and coral ledges. Despite their fairly large adult size (21 inches is the record) they are only occasionally seen as a food fish, and there have been reports of ciguatera poisoning from eating them. Yet, they still have some value in commercial food fisheries. Juveniles of the species are known to migrate with floating debris, sometimes over large distances. There are reports of these migrating juveniles changing color to match the materials they migrate with. Slingjaw wrasses will undergo at least 2 color changes over the course of their life (not including the alleged chameleon activity referenced above). As juveniles they are often green and brown with white line and black spots, and these will turn into goldish dark brown adults with white heads and some bright mottling along the side. Some of them will turn into stunning Golden Females, which can, in turn, morph into the colors of the adult male. Some juveniles will segue directly into this adult male coloration. Individual specimens are frequently recorded in between these colorations offering some amazing combinations!
Keeping Epibulus insidator is very straightforward. They are a hardy fish, that does well in reef environments, though as they age they will potentially be a threat to small fish and shrimp in the aquarium as this is their natural food. They are a shy species that gets along well with other appropriately sized fish, as long as those fish are not overly aggressive. Over time, Slingjaw Wrasses will come to recognize keepers as a source of food and there are multiple videos of them feeding from their aquarists hands. This being said, they shouldn't be kept with other fish that are a similar size and shape as they can be territorial with other slingjaws and fish that look the same. One of the most interesting things about the slingjaw in the home aquarium is its feeding behavior and thus some live food like feeder fish and ghost shrimp will likely be a part of its feeding regimen. Obviously these fish and shrimp should be saltwater appropriate and gut loaded when possible. Nutritionally they will need more than this, and luckily they generally segue over to thawed preparations and high quality pellet foods quickly. As referenced earlier, they are likely to grow to 15 inches long at least and as such, a large aquarium will be needed for them as they grow.
If you're an aquarist with a large aquarium and a penchant for interesting fish, Epibulus insidator should certainly be an option for your display. Give them plenty of hiding places, and occasionally some live food and they'll make one of your most interesting additions. Give your LFS a heads up and ask them about finding you a Yellow Slingjaw from Quality Marine today!