Leopards for the Reef (Full Article)Author: Bob Fenner
Once considered difficult to keep, wrasses of the genus Macropharyngodon are good candidates for modern reef systems with plenty of hiding places and passive tankmates.
The common name “leopard wrasses” might imply that these members of the Macropharyngodon genus are as tough as big cats. Unfortunately, that is not the case, as the common name mainly refers to the spotted appearance sported by most members of the species. The wrasses’ stealthy, stalking feline behavior is also reminiscent of their namesake.
The 10 or so described species of leopards are small (reaching only 4 to 6 inches at maximum) and feed by sifting the sand and searching for small invertebrates among the live rock. They are extremely shy overall and can only be kept healthy and happy for any real length of time in an established reef system of good size. Unfortunately, even when provided a large, established reef, many specimens die within a few weeks of capture due to stress from collection and transport.
Species on Parade
Several species are somewhat commonly available, though none are available all the time.
Rare Wrasse Macropharyngodon bipartitus
M. bipartitus comes from the western Indian Ocean. It grows to about 5 inches in length. Like most members of the genus, it exhibits sexual dichromatism (exhibits a different color depending on the gender of the individual) and is a protogynous hermaphrodite (it begins its lifecycle as a female and becomes a male with increased dominance status).
Choat’s Wrasse M. choati
Coming only from east Australia, M. choati are rare and expensive. This is a small species that reaches up to 3 inches in length. While many in this genus display orange or red coloration, typically in the form of highlights, it is usually against a green or dark background. This species is unique in that it features orange or red coloration on a silvery background, which makes for an interesting contrast.
Potter’s Leopard Wrasse M. geoffroy
Being a Batesian mimic of Potter’s dwarf angelfish Centropyge potteri, M. geoffroy is often called the Potter’s leopard wrasse. Its range is from Hawai‘i to Micronesia and the East Indies. This is a very delicate species.
Guinea Fowl Wrasse M. meleagris
M. meleagris is the most common species in this genus offered to the aquarium trade. Simply called the leopard wrasse or guinea fowl wrasse, it is found in the Indo-Pacific from the Cocos (Keeling) Islands to the Western Pacific. Looking at one it is easy to see why these fish are associated with a leopard’s coloration. It grows to 6 inches in length.
Black Leopard Wrasse M. negrosensis
The black leopard wrasse M. negrosensis is usually offered as a miscellaneous item. Only the ones imported from Australia generally survive. It ranges in the Indo-Pacific from the Andaman Sea to Samoa. It reaches about 5 inches in length.
Ornate Leopard Wrasse M. ornatus
The ornate leopard wrasse Macropharyngodon ornatus is found in the Indo-Pacific from Sri Lanka to New Guinea. The best specimens are exported from Australia and Sri Lanka. It grows slightly larger than 5 inches.
I have alluded to these fishes’ penchant for zooming about their captive and natural reefs continuously during the day. However, they are notable for burrowing and staying under the surface of sand substrates at night, or when frightened. It is also possible that Macropharyngodon may dive into the sand on first introduction and stay there for days. This flight may not necessarily be from fear; they are likely just adjusting their circadian rhythm after having been caught and shipped through several time zones. Other than checking to see if the wrasse jumped out onto the floor, I urge patience. Do not stir the sand up to find your errant wrasse. Be assured that with time, it will resurface.
Macropharyngodon wrasses rarely harass invertebrates other than smaller worms, mollusks, and crustaceans. They get along with all other reef fishes, with the exception at times of members of their own genus. When keeping multiple leopard wrasses, place them in the tank all at once, or barring this, introduce only a single male per system, and a smaller, initial phase individual in turn. To be clear, only one male should reside in any given tank unless it is of huge volume, with only one female unless the system is hundreds of gallons in volume. These fishes are generally encountered in the wild in groupings of smallish females with perhaps a few sexually undifferentiated young swimming about with them in tow. Occasionally, if you have good vision and are keenly looking about, you may see a male (they are wary of divers), perhaps with a larger female in association.
There are times when similar-looking wrasse species do conflict with leopards, with some Pseudocheilinus, Thalassoma, Coris, and Halichoeres wrasses notably fighting them for territory. Hawkfishes (cirrhitids) and some dottybacks (pseudochromids) may also vie with leopard wrasses. If any of these fishes must be stocked with Macropharyngodon species, the leopard wrasses should be placed first.
Leopard wrasses can be quite hardy, but they are vulnerable to starvation like mandarin dragonets. They need to be provided with the right types of foods on a regular basis. If you doubt the sustainability of your substrates in producing such live foods, I strongly encourage that you utilize a high-quality, completely nutritious, and palatable prepared staple.
For picking out good leopard wrasses at the store, look for clean, full bodies: undamaged fins, clear, bright eyes, regular breathing and swimming behavior, and no obvious damage about the mouth. Also make sure to perform the time-tested acid test to ensure that the fish will feed on the foods that will be offered.
Smaller, initial-phase (female) individuals adapt much more readily than already-male, larger specimens. These males almost always ship poorly, being too high strung to be confined to small spaces.
I class leopard wrasses with small blennies and gobies as species that should not be left at the store too long, a few days at most, perhaps even picking up on arrival if practical. The important take-home point here is to make sure you don’t procure too-thin specimens, as these rarely rally and return to a good index of fitness.
Leopard wrasses are best kept in a well-established reef system featuring a deep, fine sandbed and copious amounts of small crustaceans, worms, mollusks, and more. These fishes are avid burrowers, hence the need for finer, rounder (not angular like silicate) sand. Sugar-fine aragonite substrate is ideal. Avoid sharper, larger grades, which cause stress, damage, secondary infection, and death. Wholesalers often get by offering a small tray of appropriate sand.
These fish require stable, optimized water conditions and a good deal of substrate-derived live food items to subsist on. The operation of a vibrant, food-culturing refugium of size is certainly a bonus in their care.
Systems under 100 gallons with less than 100 pounds of good-quality (mature but not too old) live rock need not apply, as the likelihood of success in keeping leopard wrasses in smaller systems is extremely small. They need room to move, have a sense of being able to get away, and surface area for foraging.
It is very important to completely cover the top of the system and not only have the water level down a few inches, as these labrids can really launch themselves out of systems with small-enough openings topside.
The absolute need for nutritious foods has been mentioned enough. If you can’t provide live items, frozen/defrosted meaty foods of small size (mysids, cyclops, copepods, etc.) should be offered a few times (two, three, or more) a day, along with small pelleted food. To acquaint unfamiliar fishes with the pellets, successively mix some higher percentage of the dried sinking food in with other offerings. I’ve yet to see a fish that didn’t learn to take this food in a relatively short time.
This may perhaps be inconsistent to what you’ve heard others advocate, but I would not quarantine Macropharyngodon spp. There’s much more to be potentially lost than gained. Delaying leopard wrasse placement in a permanent display setting may bring added stress, likely damage (from the fish dashing about), and extended non-feeding. If anything, I might—if the specimens appear strong enough—subject them to a few minutes of a pH-adjusted freshwater bath to knock off possible external parasites.
Perhaps related to their adaptations to sand burrowing, these fishes rarely suffer from the usual external protozoan scourges of tropical reef fishes. If they’re to be treated for such, quinine compounds are strongly advised rather than dye, metal salts, or formalin-containing products.
Unlike many labrid genera, the sex of Macropharyngodon wrasses is easily distinguished. Terminal phase (male) individuals in good health are quite striking in appearance. Males are larger in body size, much more colorful, and definitely much shyer than females. Like other wrasses, they are protogynous hermaphrodites, first becoming functioning females from sexually undifferentiated juveniles and then becoming males.
Spawning events in captivity in hobbyist and institutional setups have been recorded, though no young have yet to be raised in captivity.
Providing a Home for Leopards
There were times when virtually all imported Macropharyngodon wrasses died within days to weeks of collection. It is likely that still more than half don’t survive the travails of collection, holding, and shipping. Many also meet their maker through improper housing and/or lack of available amounts of useful foodstuffs. Despite all this, you can successfully keep these wrasses given practice at selecting good individuals and providing for their basic care as outlined here. Yes, the odds are not super when keeping these fishes, but their collection, holding, and shipping have greatly improved in recent years. Your likelihood of being able to buy successful specimens is good.Should you have a very well-established, large, healthy reef tank and are looking for a small, colorful fish addition that exhibits interesting behavior, consider the leopard wrasses.