Catfish of the Month Right Arrow August 2020


Spotted Hoplo - Hoplosternum punctatum   Meek & Hildebrand, 1916

Article © Casey Meanney, uploaded August 23, 2020.

Friend of the forum, Casey Meanney, was good enough to write her first CotM article following a forum thread that showed this species in a great light with some nice pictures of healthy fish. Her enthusiam for this species and the fishkeeping fun it can provide is clear to see in what's written here.

From an already underappreciated genus of catfish, there is a lesser known species called Hoplosternum punctatum. For those familiar with the genus Hoplosternum, most are familiar with their larger cousins. While great fish, many with smaller aquaria may think to miss out on this genus.

That is where Hoplosternum punctatum shines. Its common name is "Spotted Hoplo", which is shared - confusingly so - with its much larger cousin Megalechis thoracata, which is less accommodating in a tank less than 55 gallons. For the sake of differentiating, this article will refer to the scientific name which is also my own preference. Hoplosternum punctatum remains smaller in the three to four-inch range, unlike all the larger Hoplosternum catfish. This size makes it a good candidate looking for a medium sized catfish for a medium sized community, or even smaller communities.

I have noticed there is little documented experience with keeping this species, which is truly a shame as it is a gem. Easily confused with Dianema longibarbis, some have found the species they keep being a mix up of the two. This has been the case between a fellow hobbyist and myself discussing how to tell them apart. Referencing a book and the sites we have access to, a few differences were noted. Discussions were made with other catfish enthusiasts and the most prominent features of H. punctatum was the presence of mottling in the dorsal fin versus the lack of in D. longibarbis and the location of the eye between the species. H. punctatum has a more central eye, lining up with the lateral line straight to the tail, while D. longibarbis exhibits a larger eye, lower in the skull. D. longibarbis also consistently shows a stronger line of spots along the lateral line, though it has been noted some H. punctatum show a similar trait.

The upkeep of H. punctatum is easy. They enjoy sand to shuffle through, rocky caves or pottery to hide inside, and leafy plants to rest on. They are quite active, using the full length of the tank they are in, so one may consider this in choosing a living space for them. I would consider a three-foot tank to be the minimum housing for a trio of this species. While they rest a lot on the substrate, they do utilize all levels of the tank, even investigating other fish they happen across. This is an outgoing species, curious and sociable. A group of three or more is recommended, as it will bring out more of their interactions, while also being playfully aloof at times.

All food is relished. Flakes, sinking catfish tabs, pellets, live foods, frozen foods, but showing little interest in smaller tankmates. They learn fast where food is expected and may even skim the surface of the tank making smacking sounds looking for expected morsels. They are brave enough to eat from hands and use their whiskers to taste hands should they invade their tank during maintenance.

They do not seem fussy with tankmates, but they are rowdy and active, so some species of slower moving fish may not appreciate their playfulness. Corydoras species are especially good tankmates with them, the two often shoal together and rest together. Their habits are similar in the way they sift sand for food and the way they rest. They are less timid than their smaller cousins and seem to boost the Corydoras' confidence as well. H. punctatum is active both day and night, which brings much activity to its home, though may annoy some more reclusive tankmates. This fish may out eat some slower feeders but is not aggressive with feeding.

This fish is robust and hardy, enjoying a wide range of water parameters. It does not seem to mind a little current in its environment or care if there is none. Given large floating plants, this fish will enjoy exploring them, as they are bubble nesters and reportedly spawn easily in captivity. Most individuals sold nowadays are rumored to be tank raised as their native locality (Panama and in the rivers of Colombia flowing in the Pacific Ocean) is not a common collection location whatsoever. They would be at home in a biotope aquarium or in most aquariums suited for basic communities. They may dig up more delicate stem plants, so caution should be taken if a carefully aquascaped tank is preferred. Plants with strong root systems are sturdy enough to withstand the digging of this fish. They enjoy structures to rest inside during their short moments of downtime. An unglazed clay pot turned on its side or half buried in sand is much appreciated, as are smooth rocky crevices. Overhanging driftwood will soon become a place for the entire group to sprawl all over.

Sexing this fish takes a close eye but is straightforward. The most visible clue is the thickened pectoral spine of the mature male, developing a strong curve at the end and development of padding to the soft rays behind the spine. Females have thinner pectoral spines with a small hook on the end. Upon looking at their bellies, the chest plates differ between the sexes, with females having plates set apart, like an open lifevest, while males have plates touching snugly, as if a zipped-up vest. This is best viewed when the fish rests on an elevated surface where the keeper can view below, or when handling the fish. Smaller fish are not easily sexed and may need time or a more experienced eye.

Its easy-to please nature and its carefree activity are sure to win over anyone who meets this fish. I encourage anyone looking for a community friendly catfish to consider these fish. Daily interactions are joyful and entertaining as they bring any tank to life with their personable antics. Their warm-grey coloring with their spotted armor is not flashy, but certainly has its own beauty. The behavior of this fish alone demands attention and can make this fish an ideal centerpiece to the smaller aquaria.


Copyright information for the images used in this article can be found on the species' full Cat-eLog page.

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