Anthias Imposters! - The Genus Pseudanthias, Part I by Henry C. Schultz III

Sometime while pursuing an attractive aquarium fish every hobbyist will, no doubt, come face to face with an Anthias. But, it most likely is not an Anthias. Chances are good that it's a fake Anthias. Oh, it will be a real fish, all right. These fish swim with fins, breathe through gills, the whole nine yards of fishy things that fish do. But they remain fake. The good part is that these live, fake Anthias can make great ornamental aquarium fish. Unfortunately, they require more than just a reliable air pump to bring them to life in the home marine aquarium. The first edition of this multi-part series on Anthias will cover the fake Anthias - Pseudanthias, yet still called Anthias by home aquarists and sport divers alike.

Well, I hope all the talk of Anthias and fake Anthias doesn't have you confused yet. I usually like to try to save the confusing part of my columns for all the scientific mumbo-jumbo, which I doubt many of you read anyway (my apologies to our scientific editorial staff - I love you guys!). The truth is, these Anthias are downright terribly confusing in terms of taxonomy. Usually, ichthyologists can blame the confusion on the fish and claim degrees of difficulty in identification. For the most part that remains untrue with Anthias. Oops, I mean the fake Anthias. Now I'm confusing myself!

The marine fish family Serranidae is home to well over 400 species of fish. Many large fish comprise this family, most notably the groupers and basses. However, one subfamily exists that includes vividly colored, ideally-sized aquarium fish. That subfamily is Anthiinae, commonly called the Anthias, and so the confusion shall commence.

The very first known Anthias was discovered in 1758 by Linnaeus. He did the world a kind favor of naming his new genus of fish Anthias. I guess he was really fond of the name; he chose anthias as the species name, also. So, we have Anthias anthias of the subfamily Anthiinae. This was only the first fish of the genus that was discovered. Can you see where this is going?

Anthias anthias became the family's type species, and thus has doomed aquarists to confusion ever since. That is because it is an Atlantic species and virtually all Anthiinae kept in marine aquariums are from Pacific waters. Over the years more than 100 fish have been errantly classified into the Anthias genus. Today, ichthyologists feel they have things on the up-and-up, but much work remains to be done.

Pseudanthias, the focal point for the next two months in Fish Tales, can be perfectly translated from Greek into English as "fake fish." The genus was originally described by Bleeker (1871), but was disregarded throughout most of ichthyological history, including in revisions as recent as Randall (1981). More recently, it was named a synonym of Anthias by Heemstra and Randall (1986). Repeated attempts to vindicate the genus (Katayama in Masuda et al, 1984; Katayama and Amaoka, 1986; Randall and Hutomo, 1988; Randall and Allen, 1989; Baldwin, 1990; Heemstra & Randall, 1999) may have finally been successful within the scientific community. Among aquarists and sport divers, however, I doubt anything will ever change - they will remain Anthias forever.

Amid the confusion over whether Pseudanthias really even existed or not, additional new genera were added as more formal descriptions of Anthiinae were released. Among them was Mirolabrichthys (Herre, 1927). It was Randall and Lubbock (1981) who finally merged Mirolabrichthys as a subgenus of Pseudanthias. Randall did so because Herre originally used two opercular spines to differentiate Mirolabrichthys from the normal three opercular spines of Pseudanthias, but this no longer held true once additional species were added to the genus. Allow me to return to Herre for a moment. In Herre's release of Mirolabrichthys, he formally described two new species. Continuing the established theme of quirkiness for this genus, we now know those two fish as Pseudanthias tuka and Pseudanthias tuka (this is not a misprint, he really did name two different fish the same name). To Herre's credit, though, attempting to classify P. tuka has confused many an ichthyologist. In subsequent research performed by additional ichthyologists, P. tuka was awarded a subspecies (Whitley, 1964), and then was subsequently stripped of that subspecies (Randall and Lubbock, 1981).

Franzia, another subgenera of Pseudanthias, has an original description dating back to 1914. Back then Jordan and Thompson (1914) were under the impression that Franzia warranted its very own genus. Various authors agreed with that summation over the years including Kendall (1984) and Katayama and Amaoka (1986). Not long thereafter the tide to began to shift, however, and less than two years later Franzia was reclassified as a subgenus of Pseudanthias (Randall & Hutomo 1988).

In total, 61 species have been classified under the Pseudanthias name. The three species of the subgenus Franzia all have a heavily scaled dorsal and anal fin. Additionally, the third dorsal spine becomes longer in males than in females. Mirolabrichthys is most recognizable by its deeply forked caudal fin, although this should not be considered a reliable character. Males do develop a telltale characteristic, however: an enlarged upper lip clearly differentiates these species from subgenera Franzia or Pseudanthias. The Pseudanthias subgenus seems to be a collection of the Pseudanthias species that couldn't be classified among either of the other two subgenera. The only true hard and fast indicator is the adult males' lack of an enlarged upper lip. Of course, if the fish is a female this knowledge is of little use. The dorsal spines, unlike those in Franzia, can be highly variable while the caudal fin, unlike that of Mirolabrichthys, is also highly variable.

Pseudanthias dominate reefs throughout the Indo-Pacific region. Very few species are geographically limited, and most can be found at several locales and even in both the Indian Ocean and Pacific Oceans. For example, P. cooperi has been charted from East Africa, north to Japan and south to the Great Barrier Reef. However, a few species are fairly limited in their geographic distribution. Pseudanthias hawaiiensis is one such example. Although its name may imply that it can be found only in waters encompassing Hawaii, Johnston Atoll is another prime location to find this species. Even more limited in distribution is P. heemstrai. One would need to travel not just to the Red Sea to see this beauty, but more specifically to the Gulf of Aqaba - the northeast finger extension of the Red Sea - to have the opportunity to witness this species in its natural environment. In contrast, 17 separate species have been collected or photographed around Japan, 15 around the Great Barrier Reef, and an amazing 22 distinct species can be found in Micronesia.

The depth range of Pseudanthias is highly variable. Because there are over 60 species in the Pseudanthias genus, it should not be surprising that I am unable to generalize the genus as a shallow water species, a deep water species, or otherwise. And despite some species being found in shallow depths, while others are found in considerably deeper waters, all species have a great depth range within their own respective species. Whether we are discussing 5' of water (or 200') for Dispar Anthias, or we are at 650' (or 85') with the Hawaiian Longfin Anthias, one thing all Pseudanthias species share is the desire to shoal in large, often overwhelmingly large, schools of fish. At times numbering well over 1000 individuals, Pseudanthias schools prefer to swim in open water just off the edge of a coral reef wall or steep drop-off. Within these large shoals the dominant males hang loosely around their guarded females. Territories guarded by the males can range anywhere from 5 - 32ft² in size (Michael, 1998). Females spread themselves out accordingly among their dominant males, while the subordinate males assume their position at the bottom of the shoal awaiting the opportunity to prove themselves worthy of advancing up the hierarchy.

Species found in shallower water generally congregate around extensive coral growth, which provides them ample places to hide from predators or to sleep in seclusion overnight. But during daylight hours the swarms of fish remain several meters off the reef feeding. The reef wall is regularly blasted with vigorous water movement, which brings food not only to the corals, but also to the Pseudanthias. The Pseudanthias always face into the current and swim at a speed equal to the current's, in such a manner that they literally swim in place. When the water current changes directions, almost in complete unison, the entire aggregation of Pseudanthias turns with it.

The deeper water species do not relate to the expansive growths of hard corals, which are obviously not present at depths such as 600'. Instead, they prefer overhangs, caves, caverns and crevices, which serve as their security blanket. Unlike the shallow water species, the deep water individuals prefer to remain close to the substrata, usually not rising more than one meter from the ocean floor. Additionally, the deeper dwelling species do not congregate in enormous shoals as do their shallow water counterparts. In all cases, however, when threatened by predators or given the onslaught of nightfall, the Pseudanthias hide deep within the reef's crevices.

Okay, so now you know where the Pseudanthias hunt for food, and you are also aware of how the food is brought to them, so it is time to discuss what actually comprises this food. In the generic sense, it would not be wrong to classify all Anthias as planktivores but, for my preference, this really doesn't narrow down their diet enough. Randall and Lubbock (1981) performed a gut analysis of Pseudanthias pascalus, which helps to define the diet of not only this species, but the entire Pseudanthias genus. Through a collection of seven specimens the ichthyologists were able to determine that nearly one-quarter (24%) of their diet was decapod copepods, another 19% was cyclopoid copepods, 9% was fish eggs and 36% was unidentified crustacean fragments. Crustacean larvae, amphipods and ostracods made up the rest of the diet.

As ichthyologists collected and studied Pseudanthias, a correlation between the total number of individuals collected versus the number of males present was in stark contrast to male/female distributions found in other species. On average, it seems only one male may exist for up to eight females. The unusually overwhelming number of species found in aggregations gave curiosity to ichthyologists, given the low number of males they were collecting from these harems. Subsequent research showed P. squamipinnis to be protogynous hermaphrodites (Fishelson, 1970; Popper and Fishleson, 1973). Further research showed Pseudanthias pascalus to exhibit the same trait (Katayama, 1974). Today, ichthyologists now believe all Pseudanthias species to be protogynous. Additionally, many of the Pseudanthias are both dichromatic and dimorphic, as will be rather apparent as I progress through the photos of specific species.

Spawning for Pseudanthias is seasonal, but boy, do they get busy when it is their season! Depending on species and locality, Pseudanthias generally spawn during the cooler winter months or the warmer summer months. Thus, Pseudanthias spawns only for roughly three months out of the year. During these three months, however, Pseudanthias spawn nightly at sundown. The non-territorial males always hang near the bottom of the aggregation, awaiting an opportunity to sneak in and release sperm unnoticed. However, it is the dominant male which gets the ladies in the mood. With all fins flared and flashing, the dominant males zigzag around females or make repeated "U-dives" toward the seafloor. When a female is receptive, the two swim in unison ahead of the remaining individuals and release their eggs and sperm. Males repeat the process with many different females throughout the evening, but it is believed that once a female has released her eggs, she is done spawning for the evening. Anthiinae are broadcast spawners, and thus their fertilized eggs free-float around the ocean as part of the zooplanktonic food chain until they metamorphose and settle to the substrate.

This is actually a rather tricky section to cover this month; possibly the most difficult in the history of Fish Tales. This is not only because of the sheer number of species in the genus, but the fact that each one has distinctive characteristics affecting its captive care. Therefore, I've chosen to give some of the basic, yet genus-encompassing tidbits in regards to the genus' captive aquarium life in this section, and then in the column's conclusion next month I will go into great detail on each particular species of Pseudanthias that regularly show up in the aquarium trade.

One of the bigger concerns with Anthiinae is modeling a productive assemblage of community fish. More often than not Anthiinae are very aggressive toward their conspecifics. However, outside of their own subfamily, Anthiinae, for the most part, are not the aggressors in an aquarium. Small fish such as gobies or blennies are seldom in harm's way, especially if they are of the sandbed-dwelling type. Wormfishes and other small dither fish may have problems co-existing with Anthiinae but, as a whole, Pseudanthias leave other aquarium residents alone provided they do not feel threatened by them. Of course, "threatening" is not just reserved for larger fish, but also fish that occupy the same niche in the aquarium or maintain the same feeding strategies. If the Pseudanthias feels threatened by the feeding tendencies of a Flasher wrasse, for example, expect the Pseudanthias to chase away the competition. On the other hand, large predatory fish should be avoided. This includes such fish as Lionfish, larger groupers, large Moray eels and Scorpionfish. Pseudanthias generally remain fairly small - a good-sized snack for the aforementioned species.

Compatibility chart for Pseudanthias species:

Fish	Will Co-Exist	May Co-Exist	Will Not Co-Exist	Notes
Angels, Dwarf	X			Should make good aquarium mates.
Angels, Large	X			Should make good aquarium mates.
Anthias		X		Highly dependant upon species. See species description in Part II for more information.
Assessors	X			Should make good aquarium mates, but Assessor will hide a lot. Add the Assessor first.
Basses	X			Should make good aquarium mates.
Batfish	X			Should make good aquarium mates.
Blennies	X			Should make good aquarium mates.
Boxfishes	X			Should make good aquarium mates.
Butterflies	X			Should make good aquarium mates.
Cardinals	X			Should make good aquarium mates, but Cardinal will hide a lot. Add the Cardinal first.
Catfish	X			Should make good aquarium mates.
Comet	X			Should make good aquarium mates. Comet will hide during daylight hours.
Cowfish	X			Should make good aquarium mates.
Damsels		X		Damsels may become overly aggressive.
Dottybacks	X			Should make good aquarium mates.
Dragonets	X			Should make good aquarium mates.
Drums	X			Should make good aquarium mates.
Eels		X		Small eels will be fine, but large, aggressive eels must be avoided.
Filefish	X			Should make good aquarium mates.
Frogfish			X	May consume Pseudanthias.
Goatfish	X			Should make good aquarium mates.
Gobies		X		Stick with the sand dwellers and all will be fine.
Grammas	X			Should make good aquarium mates.
Groupers			X	May consume Pseudanthias.
Hamlets			X	May consume Pseudanthias.
Hawkfish		X		Smaller Hawkfish are fine, but larger ones may harass and attack Pseudanthias.
Jawfish	X			Should make good aquarium mates. Add the Jawfish first and allow to settle in.
Lionfish			X	May consume Pseudanthias.
Parrotfish	X			Should make good aquarium mates.
Pineapple Fish	X			Should make good aquarium mates. Pineapple Fish will hide during daylight hours.
Pipefish			X	Best kept in an aquarium by itself.
Puffers	X			Should make good aquarium mates.
Rabbitfish	X			Should make good aquarium mates.
Sand Perches	X			Should make good aquarium mates.
Scorpionfish			X	May consume Pseudanthias.
Seahorses			X	Best kept in an aquarium by itself.
Snappers			X	May consume Pseudanthias.
Soapfishes			X	May consume Pseudanthias.
Soldierfish			X	May consume Pseudanthias.
Spinecheeks	X			Should make good aquarium mates.
Squirrelfish			X	May consume Pseudanthias.
Surgeonfish	X			Should make good aquarium mates.
Sweetlips			X	May consume Pseudanthias.
Tilefish	X			Should make good aquarium mates. Add the Tilefish first and allow it to settle in.
Toadfish			X	May consume Pseudanthias.
Triggerfish		X		Highly dependant upon the Triggerfish's personality.
Waspfish	X			Should make good aquarium mates.
Wrasses		X		Most should make great aquarium mates. Avoid Flasher wrasses.

Note: While many of the fish are listed as possible tankmates for Pseudanthias species, you should research each fish individually before adding it to your aquarium. Some of the mentioned fish are better left in the ocean or for advanced aquarists.

Good aquarium tankmates for Pseudanthias include Surgeonfish, Butterflyfish, both large and dwarf Angelfish, and most passive fish that remain on the sandbed. Other small open-water swimmers, such as wrasses from the genus Cirrhilabrus or Macropharyngodon, can be mixed successfully provided ample room, food and hiding spots are available.

Motile invertebrates are, for the most part, not at risk. Cucumbers, starfish, urchins and even most shrimp of the cleaner varieties are plenty safe sharing the aquarium with Pseudanthias. Those that are at risk, however, are small decorative shrimp that are not known cleaners, and even some of the smaller cleaners are at risk. If it appears the shrimp could be consumed whole by the Pseudanthias, there is a mighty fine chance it will do just that. A quick look back at the family lineage reconfirms that they are, in fact, part of the Grouper family, and as such we should consider them highly predatorial despite their diminutive size. Sessile invertebrates, however, are at no risk whatsoever.

Food items for the Pseudanthias are definitely another area which I can discuss for the group as a whole. All of them are planktivores, and all of them are voracious eaters in the wild. A few species have difficulty converting to prepared foods in an aquarium, but as a whole, the genus adapts well to captive foods. Mysis species shrimp should be the staple of their diet, whether they are frozen/thawed or freeze-dried. That alone will keep your Pseudanthias healthy, but a highly varied diet will help keep the fishes' brilliant colors. Gut-loaded brine shrimp or bloodworms will be eagerly consumed, and over time the Pseudanthias will begin to accept as food most anything the aquarist drops into the aquarium, including dried vitamin-enriched pellet foods.

Getting enough food to Pseudanthias is perhaps the biggest obstacle to overcome when keeping Anthiinae. In the wild they consume gross amounts of food. They do not swim great distances as do Surgeonfish, but only because Pseudanthias swim in place. They do, however, swim almost constantly, thereby increasing their demand for a nearly continual food source. Additionally, the aquarist will need to provide a very high water flow rate in their aquarium to mimic their natural environment - thereby increasing the metabolism of the fish itself just to mimic natural conditions. A minimum feeding of twice daily is required to maintain the weight of these highly active fish. In addition, it would be proactive to also have a functioning refugium attached to the aquarium, which is able to provide a continual natural, live food source for Pseudanthias. Although not essential, it is ideal.

Aquarium size is not a great concern despite the high rate of activity displayed by Pseudanthias, mostly because their energy is generally expended in one place. A fair comparison is that if we could place Surgeonfish on treadmills in our aquarium, it would be much the same situation. That, in conjunction with their genus-wide small size, makes these a great aquarium fish for smaller aquariums - provided the aquarist can meet the demands of a highly fed fish. If we were discussing only a single Pseudanthias in the aquarium, it could easily get by with a standard 40-gallon tank. The greater concern comes, however, when these fish begin to mix with other species, or even their own species. That, however, will be where I pick up on this topic next month.

In the conclusion of Anthias Imposters! - The Genus Pseudanthias, Part II, I will discuss the species in great detail, which will include more on their husbandry, possible tankmates and other information specific to each species.