Thursday, September 11, 2008

THE ANYPERODON GROUPERS

An unusual color form of the whitelined grouper. It lacks white stripes and sports a series of orange spots. This individual may be an adolescent on the way from changing from a juvenile to an adult, however, it does not look like the transforming subadult below. Instead, it could be that this species exhibits a different coloration as a juvenile in the Indian Ocean because it is mimicking Halichoeres timorensis, which has orange spots rather than orange stripes! I photographed this fish in the Maldives.

The family Serranidae is one of the largest teleost families represented on coral reefs with around 450 species. Most groupers are easily identified, exhibiting somewhat of a stereotypical fish shape. Most are not brightly colored, sporting “reef tone” attire to help them blend in with their surroundings. (Many are ambush predators that rely on going unnoticed to catch their prey.) The only described grouper in the genus Anyperodon, the whitelined grouper (Anyperodon leucogrammicus), is somewhat atypical for a serranid. It is more elongate, with a sharper snout.

The juvenile whitelined grouper mimics certain initial phased Halichoeres wrasses, which aids them in capturing small fishes. The mimic even has the ocelli, characteristic of the model (see the model below). Photographed in West Papua.

The model - an initial phase Halichoeres melanurus. Photographed in West Papua.

As a juvenile, this grouper is an aggressive mimic, resembling the initial phase color form of a variety of Halichoeres wrasses (e.g., Halichoeres melanurus). (The resemblance is truly remarkable, as you can see from the accompanying photographs.) The young grouper has different diet than the wrasses it resembles - the former eats small fishes and crustaceans, while the labrids ingest small, benthic invertebrates. As a result, prey items that would not be concerned with the approach of the labrid may fall prey to the larger-mouthed “wolf in sheep’s clothing” (that is, the juvenile A. leucogrammicus)! The young whitelined grouper will actually associate with the model and has been observed to capture small damsels that ventured to close. As the whitelined grouper grows larger, the coloration undergoes a metamorphosis. The adult has white stripes that running along the body and orange spots all over the head and body.

A subadult whitelined grouper - it still has the orange stripes of the juvenile, but also has the white stripes of the adult. The ocelli have also disappeared. Photographed in Papua New Guinea.

The adult whitelined grouper - note the elongated body, sharp snout and characteristic coloration. Photographed in Lembeh Strait, Sulawesi.

A number of years ago, a friend of mine, Jim Walters (Old Town Aquarium), sent me an even more amazing fish. It was obviously an Anyperodon sp., but it was metallic blue! It also had black stripes, a white stripe and white blotches along the flanks. There were spots on the rear base of the dorsal fin and a black bar at the base of the caudal fin.

The amazing metallic blue grouper, a species only known from Saudi Arabia, still awaits formal description.

The fish, which I refer to as the metallic blue grouper, was collected in Saudi Arabia in deep water (I was told it was captured at a depth of around 60 m). I have not seen a specimen since Jim sent me that fish (this individual went into formalin and was shipped to the Bishop Museum), but recently I received a very interesting email from a fellow grouper fan, Ivan Alfonso. He was able to get a hold of three specimens and sent me photos. They looked similar to the individual pictured here, except the bar at the base of the caudal fin had broken up into three spots bordered in white in one fish. Ivan tells me that the species can get at least 24 cm in total length. It may be that the blue becomes less intense as the fish grows larger. I am hoping to get another specimen so DNA analysis can be conducted to compare it with A. leucogrammicus.

If you have a large enough tank, the Anyperodon groupers make wonderful aquarium pets. They are quite secretive when first added to the tank, so provide a nice cave or overhang as a shelter site. But as time goes on, and they begin to recognize you as a food source, they will become more tame. You may need to use gut-packed ghost/glass shrimp or mollies to initiate a feeding response. They can be aggressive toward other groupers (including members of their own kind), if space and hiding places are limited. They might also be the target of an aggressive confamilial. In most cases, size and prior residency will determine which serranid is boss of the tank. Feed your Anyperodon to satiation several times a week. Of course, any fish or crustacean that can be swallowed whole will be, so select tankmates carefully.

©2008 Scott W. Michael

4 comments:

Jake Adams said...

Glad to see you're back with some fresh fish posts, looking forward to more. Nice one with the Anyperodon groupers.

Scott Michael said...

Thanks Jake! Have you seen or kept the blue Anyperodon? It is an amazing fish!

Jim Walters said...

Before the collection station in Saudi stopped shipping to the states we were able to acquire 5 blue Anyperodon over an appx. 9 month time span.

Scott Michael said...

Hey Jim! Thanks for the input. If you see any more, let me know! How are they in the aquarium Jim? Have you found them to be reclusive? Aggressive? Any other interesting, unique behavior/care requirements?