A new species of miniature bagrid catfish has been described from southern Borneo.
Its description as Nanobagrus immaculatus by Heok Hee Ng of the National University of Singapore has been published in the most recent issue of the journal Copeia.
Nanobagrus immaculatus can be distinguished from other members of the genus in having a uniformly dark-colored body lacking pale spots or patches, larger eye and a longer adipose-fin base.
The new species is typically found in blackwater habitats in the Kahayan River drainage in southern Borneo, although personal experience in maintaining this species in the aquarium indicates that it is adaptable to non-blackwater conditions (this species has very recently been exported for the aquarium trade).
Nanobagrus is also rediagnosed in this study as miniature bagrid catfishes (maximum size under ca. 45 mm SL) with a reduced supraoccipital process;,reduced anterior nuchal plate element, and a large, prominent posterior cranial fontanel.
The species formerly known as Pseudomystus fuscus is also reassigned to Nanobagrus in this study.
For more information, see the paper: Ng, HH (2008) A new species of Nanobagrus (Teleostei: Bagridae) from southern Borneo. Copeia 2008, pp. 93"98.