Among the most common species of Hypancistrus in the hobby is L201 from Rio Orinoco. It's a small species, with a black body covered in numerous small white spots. It's often confused with the larger Hypancistrus contradens, and it's often exported together with that species and Hypancistrus lunaorum (L339). Beware of crossbreeds!
Name: Hypancistrus sp.L201
Trade names: L201
Origin: Rio Orinoco, Colombia/Venezuela
Maximum size: 10 cm / 4''
Compared to the similar Hypancistrus contradens, L201 is smaller, has a lower body and a shorter head. Usually the spots are smaller than what is common in Hypancistrus contradens, but the spots in L201 can vary somewhat in size and numbers. The similar L339, Hypancistrus lunaorum, can be told apart from L201 by the same traits as with Hypancistrus contradens, but Hypancistrus lunaorum has very small spots, and often just a few of them. There is an even smaller Hypancistrus form from Rio Ventuari that is very easy to confuse with L201. This form is erroneously traded as L280 (which actually belongs to Micracanthus vandragti!), and is said to be full grown at about 6-8 cm.
L201 needs an aquarium set up consisting of lots of hiding places in the form of rocks, wood and of course specially made caves that suit their measurements. In these the males will eventually guard their offspring. They prefer water that is fairly warm (27-30 C), soft and slightly acidic. Most of all it should be well oxygenated and clean, so a good filtration system and frequent water changes are essential. It's a rather small and timid species that should not be exposed to too much competition over food and shelter. Among themselves they are fairly peaceful, although males may quarrel for caves and females can sometimes be badly injured or even killed during the breeding-trapping in the male's cave.