In a hobby obsessed with the likes of Panaque and Pseudacanthicus, who will champion the smallest suckermouths? Daniel Konn-Vetterlein, that’s who.
THE BEAUTIFUL TONGUE-TWISTER Hypoptopomatinae refers to the subfamily of those small loricariid catfishes that are known in the hobby as ‘otos’. In the trade, the ‘oto’ is in fact a mix of species that are superficially very similar to each other and vary depending on the season, the exporter, and the country respectively. Mostly the ‘otos’ we see in stores are Otocinclus macrospilus, or O. huaroni, which are often offered as algae eaters for small tanks. But there’s so much more to this subfamily, and there are many more dwarves to look out for.
Despite the approximately two hundred known species, as well as the still-undescribed forms, the real extent of the diversity in this group is only known by a few aquarists. The recent description of the new genus Rhinotocinclus with the well-known type species R. isabelae (Reis & Lehmann, 2022) as well as the renewed availability of the Parotocinclus genus from Brazil are reasons enough to take a closer look at some species that appear in the hobby from time to time.
Elusive zebras
For example, every autumn we receive individuals of the remarkably pretty ‘zebra oto’, Otocinclus cocama. Its attractiveness, as well as its only temporary availability, inevitably lead to it being comparatively highly priced, and far from being sold as part of a ‘clean-up crew’, it is instead graced with specially equipped species-only tanks. Reproduction has only been successful on rare occasions so far, and without recurring imports, the species wouldn’t be represented in the hobby for long.
That said, spawning is indeed possible. Like Corydoras catfish, the female cleans potential egg-laying sites and swims frantically around the tank. If a male notices her activity, both start to swim together to the spawning sites, with the male occasionally cleaning as well, until the female sticks her eggs either individually or in small numbers on to leaves. No parental care is offered by either parent, but the eggs and young fish are not harassed either.
After about 72 hours hatching begins, after another 96 hours the yolk sac is consumed, and pigmentation starts to show. Only after two weeks can you see that the young fish is an Otocinclus cocama.
The first zebra oto reproduction that I know of took place in a 20-litre tank. Although their home can be somewhat la
