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One of the most popular L-numbers is L333. This Hypancistrus represents a highly variable species from the Rio Xingu, Brazil, and shares the typical wormline pattern which is so common among the Hypancistrus forms in this river. Because of the similarity with L66, a different morph of the same species, crossbreeds are unfortunately not uncommon, so be mindful when you purchase tank bred individuals. Currently L333 is allowed for export from Brazil, and because of its distribution range, it may not face extinction because of the Belo Monte dam.
Facts:
Name: Hypancistrus seideli (Sousa, Sousa, Ribeiro, Sabaj, Zuanon & Py-Daniel, 2025)
Trade names: L333
Origin: Rio Xingu, Brazil.
Maximum size: 18 cm / 7”
Rio Xingu is home to many similar looking Hypancistrus forms of the same species. Although they are variations (morphs) of the same species, keeping the forms separated in captivity should be the rule in order to avoid a blurry captive strain in the future.
L333 is possible to recognize with its large adult size, not very forked tail and a body that is stockier and slightly higher than L66. L333 is usually more yellowish/cream coloured than the more grey/white L66, but even individuals of L333 with a white base colour are common. Compared to different morphs like L399/400, L333 usually shows a more consistent line-pattern that is not broken up into dots. Separating L333 from L401, a form from the Alenquer area, is close to impossible, and they may well be the same species.
In young fish, the pattern of L333 can be very striking, with just a few, broad (or thin), black lines against a very light, golden body. Such specimens were initially thought to be a different form (L236), but we have since learned that this pattern is a mutation that sometimes occur in most of the types of Hypancistrus in Rio Xingu. Through line-breeding in captivity this type of pattern has been stabilized. Adult specimens, males in particular, can become very grey and dull coloured with their body almost covered in odontodes.
They need 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. 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. Males develop longer odontodes on their pectoral fins and on their cheeks, and have broader heads. Hypancistrus are mostly carnivorous, so a selection of crustaceans, insect larvae and fish meat should be offered along with high quality dried foods that also contain some vegetable matter.
More info: