Spatuloricaria evansii

Remarks:  Despite having been known to science since 1892, little is recorded about Spatuloricaria evansii aside from its geographic range and morphology. The holotype for this species of whiptail was originally collected from Mato Grosso state in Brazil by geologist John William Evans after which it was named. It’s now known that the native range of S. evansii extends beyond this collection point and encompasses the Paraguay and Beni river basins that stretch across Argentina, Bolivia, and Brazil.

  The build of S. evansii is typical of most rapids-dwelling Loricariids with a flat, elongated body that helps it withstand the fast currents. A natural, mottled, tan, gray, and brown pattern is also a useful adaptation as it allows them to naturally blend in with the rocks they hide amongst. Like many whiptails in their range, S. evansii also have wide, gray bands that run up the length of their body that vary in visibility and hue based on the fish’s mood. When mature, males can be told apart from females by their thicker but shorter cheek and pectoral fin spines, more narrow head shape when viewed from above, and the extension on the top of the caudal (tail) fin being far longer and thread-like.

    As they are a rapids-dwelling species, S. evansii require pristine water and high levels of dissolved oxygen to thrive. While they can reach nearly a foot in length, most aquarium specimens top out around 8”. This still puts them on the larger side for a whiptail and thus need to have plenty of swimming space. S. evansii can be a great choice if you are looking for an omnivorous whiptail that won't be too much competition for species like Otocinclus catfish as they tend to not care much for algae. Instead, they should be provided a varied diet consisting of both meaty and vegetable-based foods. If all their needs are met, these whiptails can be a rare and interesting addition to your South American community tank.