The isopod hobby owes a huge amount of its success and popularity to dart frog keepers – isopods are wildly beneficial for use as feeders and cleaners for the tiny, vulnerable amphibians. When isopods were originally being marketed for frogs 20 years or so ago, there were only two main varieties: Porcellio scaber and Trichorhina tomentosa. Froggers have come away from the larger, more predatory Porcellio species due to their knack for preying on frogs, but there are still plenty of options of isopods that are compatible with frogs.
The first isopod we have to discuss, of course, is Porcellionides pruinosus. These isopods are native to the British Isles, a temperate and humid environment, and positively thrive in a dart frog setup. They’re docile, polite roommates that leave frogs, froglets, and their eggs alone, while also adventurous enough to explore the upper levels of a terrarium and clean waste. They are a moderately sized isopod, a full-grown adult can reach 12mm or so, but they have a thinner exoskeleton in comparison to other isopods and don’t cause impaction like other feeders may. Pruinosus are also available in an increasing number of colors and patterns, including: orange, oreo crumbles, powder blue, white out, creamsicle, and most recently dalmatian, orange dalmatian, and crystal.
A variety of dwarf isopods are also available for frog setups. In comparison to the Pruinosus, dwarfs are typically subterranean, meaning they inhabit the lower layer of the setup burrowing into the first few inches and staying below the leaf layer. Dwarf isopods are a fantastic feeding resource for froglets; adult Trichorhina tomentosa for example don’t reach larger than 5mm in full adult hood. Many dwarf isopods are parthenogenetic, meaning they are exclusively female and reproduce through what is called “parthenogenesis”; essentially cloning themselves. Dwarf populations have a shorter reproductive rate, and females can produce a brood as frequently as monthly if they have the right conditions. We do recommend culturing a separate group of dwarves in a reserve tank, because a motivated frog can rummage through the leaf layer and decimate their cleaners.
The first and most widely used dwarf isopod is Trichorhina tomentosa, or the “dwarf white isopod”. We’ve discussed this isopod at length, and they are perfect for frogs. They thrive at temperatures that darts prefer and love high humidity and moisture. They don’t attack larger animals and live with frogs peacefully. As discussed earlier, they are parthenogenetic and reproduce quickly.
The next most popular dwarf is Trichoniscus sp.” dwarf purple” isopods. These isopods don’t have a specific Latin scientific name and are likely 3 species being sold under the same name. They are also parthenogenetic, and reproduce quickly, although not as quickly as dwarf white isopods. Adults typically reach a length of 3mm and are not as robust as dwarf white isopods. It is also important to note that although they are known for being “purple” isopods, they are not purple; but more of a light lavender grey color.
Agabiformius lentus is our personal favorite dwarf white. They are a sexual species possessing both male and female members of the population, but still reproduce at an astounding rate. Adult A. lentus reach a size of 5mm but are more robust and wider in comparison to dwarf white. They also burrow, but adults spend a significant time on the surface just below the leaf litter. They have an interesting habit of playing dead similar to a turtle; by splaying their legs outward and holding still.
Niambia capensis, or the dwarf African cape isopod, is a dwarf that was collected from the caves of Colorado, but initially native to Africa. They are a slender isopod that typically reaches a length of 5mm. This isopod reproduces sexually and is unfortunately at a much slower rate than other dwarf species. They do well in high humidity, but often venture above the leaf layer and are prone to predation.
Atlantoscia floridana is a dwarf species native to and collected from Florida in the US. They are known by their common name “Florida fast isopod” and certainly live up to it. Florida fast isopods are fantastically speedy, and reproduce at a fast rate as well. They are slender, oval shaped isopods that reach a length of about 5mm. They do spend time above the leaf layer but are less prone to predation thanks to their fantastic speed.
Venezillo parvus, also called the “dwarf roly poly”, is a fast-reproducing dwarf isopod that rolls into a ball. Although a sexual species, they do populate a setup quickly. Parvus burrow down the first few inches of substrate and rarely venture above the leaf layer. They do have a thicker exoskeleton rich in calcium, which may cause concern for impaction in frogs. They also enjoy soft bodied plants, so should be used with caution in a terrarium well planted with sensitive species.
While there are other dwarf isopods we haven’t discussed, they are typically on the rarer edge and reproduce slowly (not to mention expensive), so aren’t recommended for a frog setup where they will be lunch. Porcellio sp. “spiky Canare”, Rhyscotus texensis, Platyarthrus aienesis, Haplopthalmus danicus and Armadillidium pulchellum are examples of such species.
We recommend avoiding all larger species of isopod, especially species such as Porcellio scaber and Porcellio laevis. Although scaber were initially first marketed for frogs; if their population gets out of hand the frogs can become lunch instead! The ravenous nature of these isopods makes them risky roommates for tender frogs. More docile species like Armadillidium vulgare, Armadillidium nasatum, and members of the Cubaris genus won’t attack frogs; but should be avoided for a different reason: they positively love plants, especially soft-bodied ones. Rare vining plants that are worth hundreds are a tasty snack for these little herbivores and they make a quick meal out of moss, vines, and leaves alike – dried or fresh. Waxy coated plants like pothos and hoya are safe from their appetite.
We would like to thank our friends at The Art of Darts, Dark Knight Exotics, and FrogDaddy for their valuable input on this article. While we do have an extensive knowledge of isopods, they provided invaluable insight to frogs, their behaviors, community trends and keeping. We hope our combined expertise helps you choose the isopods right for you!