Hoplosternum thoracatum was introduced in aquaria commerce in 1911. It`s native from the north of South America, Trinidad and Martinique. The local name is atipa. Even if in Romania it was introduced and reproduced after 1980, it has a good reputation contrary to its size of 15 cm length.
The body plaques join the back plaques. The body is strong; it has 2 mustaches pairs on the superior maxillary. The tail is a little concave and the adipose fin has a support thorn. The maximum length is 20 cm. The background is colored in grey-brown, with a darker back and white abdomen (except the spawning period). On the body it has big brown-black spots which can form a line on the flanks. The fins are grey-yellow and they have black points. On the tail there is a dark colored line.
At the age of 6 months the sexual difference is obvious. The male has longer pectoral fins than the female. The female has a larger body diameter. Usually the abdomen is colored in white, but in the reproduction period the male has a dark spotted abdomen. These fish start their sexual activity after the age of one year.
It doesn`t have special needs for the water chemistry. The spawning can take place at a temperature of 18° C, and they eat almost anything from the bottom of the aquarium. In general, they need large aquariums (about 120 liters), rich planted and with many hiding places.
Hoplosternum thoracatum builds a bubble nest at the surface of the water, under a support which can be a leaf, a plaque of glass or a polystyrene portion. Ruda Zukal mentioned that he obtained the best result with setting a black piece of plastic on the inferior part of the support. From the nest building start point, the male becomes very violent and it attacks even when we feed it. The bubble nest building can last 2 days, even 1-2 weeks. For stimulating the nest construction it`s recommended to put some oak tree leaves on the bottom of the aquarium. Normally, for reproduction they are kept in couples, sometimes 2-3 females for a male. The male will spawn with every female after a short break. The reproduction aquarium can be planted or not and can have ground or not.