J. Gosse in 1963
Distribution: Lower Rio Negro at the Solimoes confluence and the upper Rio Purus (a Rio Solimoes tributary), and other Amazon River drainages from Brazil and possibly into Guyana
Pterophyllum leopoldi, the most recent specie addition to the genus, are rare in the trade. To date I have only come across one importation of them in person and I purchased them. As angelfish go they’re quite small, reaching a length of about 4″ (10.16cm). Typical of the genus, Leopoldi are silvery-pewter with dark vertical bands, numbering up to 11 from nose to peduncle (caudal base) in this species. Three of these bands remain more or less distinct; one through the eye, one mid-body, and one that reaches from dorsal to anal fin tips, while the other bands vary in intensity or disappear altogether depending on the mood or condition of the fish. Most often there is a black patch on the upper back at the base of the dorsal fin which is sometimes used as a species identifier; however, this is unreliable because this patch is essentially the remnant of one of the vertical bars that comes and goes. There is also a large dark patch on the operculum, behind the eye at the “temple”. This can be anywhere from a bright iridescent blue to greyish-black. In some of my specimens, this patch has spread over most of the gill cover, giving the fish brilliant metalic-blue heads. As the fish age, their unpaired fins take on orangish-red or reddish-maroon hues, and an overall blue-green iridescence develops and intensifies, especially about the head and “shoulder” area, and on the rigid portions of the dorsal, anal and ventral fins. Mature specimens are beautiful and jewel-like and literally shimmer under optimal lighting. To date, these are the most colorful of the wild-type freshwater angelfish to have been discovered.
Oh, yeah… and then there’s that snout! Protruding and becoming more downward-sloping with age, giving rise to that other common name for this fish, the “Roman-nose” angelfish. Most hobbyists, however, refer to them as Leopoldi.
Immediately upon being introduced into their new home, a well-established, heavily wooded and planted 55 gallon (later moved to a similarly prepared 125 gallon), my group of 5 wild-caught P. leopoldis immediately took to picking at the filamentous algae growing on the Java fern that I had continually failed to eradicate. They also began nibbling on the fuzzy, unattached roots of the ferns, and picking bits of detritus out from between the leaves and axils of the rest of the vegetation. This, by the way, is stuff that the resident plecos, otocinclus, corys and Geophagus would not touch. These fish were not starving nor underfed when I purchased them. Not only was their weight good, but I had asked the seller feed them generous amounts of black worms so that I could see for myself that they were all eating well and had vigorous appetites. In any event, the next morning a significant amount of the algae that I had resigned myself to dealing with in this aquarium was gone!
I have long observed that P. scalare will scar plants to the point of eventual destruction and scrape algae from various surfaces in preparation for spawning, but I had never known neither wild-caught nor captive-bred angelfish to intentionally consume any plants or algae unless compressed into pellet form containing other meal or meaty ingredients. So it was surprising to see that my group of leopoldis would nibble away at nuisance algae.
With time I observed that the leopoldis relished algae wafers, vegetable pellets, and pretty much anything else offered. Interestingly, they demonstrate a complete lack of interest in the resident endler population. Newly born endlers congregate near the surface of the aquarium and venture throughout seemingly unnoticed by the leopoldis. This would not be possible with P. scalare, as even the the fanciest line-bred fish are piscivorous and predatory by nature, and will wipe out a population of any fish they could fit into their mouths, and this includes adult endler/guppy males and smaller females, and the fry of any species unfortunate enough to be born in their aquarium. I once added a small population of Moscow black guppies to an aquarium containing two black veil angelfish, smaller in body size at the time than the leopoldis. My thought was that these large, jet-black delta-tailed guppies a long with the black veils would make a striking display. The angelfish seemed to pay them little attention; however, by the next morning almost of the males and several of the smaller females were gone, and the angelfish had suspiciously swollen bellies.
Keeping P. leopoldi in well-established, densely planted aquaria would offer them constant grazing opportunities as well as sight barriers. True to the nature of other freshwater angelfish, they can be quarrelsome, and less dominant fish need to be able to find hassle-free areas of the aquarium. As with P. scalare, leopoldis are best kept in mated pairs or in groups of 5 or more to diffuse aggression. They are a peaceful species that will, like any cichlid, become extremely aggressive and territorial when breeding and rearing young. Unless the aquarium is very large, breeding pairs once formed should be isolated or the other aquarium inhabitants should be removed.