With 66 valid species (and many others still awaiting scientific description), Rineloricaria represents the largest radiation of species among the loricariine suckermouth catfishes. This distinctive subfamily is a close relation to the common “plecos” seen in the aquarium trade, but can be easily told apart by their more attenuated shape and the lack of an adipose fin.
Those in the genus Rineloricaria are generally referred to as whiptail catfishes, in reference to the long, trailing filaments of the caudal fin seen in many species. This, however, isn’t exclusive to this genus, as there are other “whiptails” seen in some other groups common in the aquarium trade, like Sturisoma and Sturisomichthys. There are some minor morphological differences that separate these, but, in practice, only a couple Rineloricaria are likely to be encountered. One is a flat, brown species known as the Common Whiptail (Rineloricaria parva), until recently known as Hemiloricaria.
The other is a mysterious species which goes by the trade name Red Lizard Catfish. This species is said to have first appeared with European breeders in the 1970’s, though it remains unclear if these were the result of captive breeding or from wild-collected specimens. There are no known species that match the beautiful reddish tone of the Red Lizard, and so it has been suspected that this is merely a variety of another common species, R. lanceolata, with which it readily breeds in captivity.
Whatever the case, the Red Lizard is highly recommendable for smaller aquariums. Mature specimens are little more than 4 inches or so in length. The sexes are similar, with males developing odontodes on the head and pectoral fins, and breeding is easily accomplished when a small cave is provided. This peaceful species is easily kept in groups, and, following mating, males guard the eggs until hatching.
Both algae and meaty foods are readily accepted. The small size of this fish allows it to clean algae off surfaces that larger plecos often miss, such as plant leaves. And unlike many plecos, their nibbling causes no damage to foliage. A bit of lettuce or zucchini is another nice treat to consider offering.