Despite its extensive natural distribution S. lilith is uncommon in the ornamental trade, where it is sometimes referred to as ‘one-spotted demon fish’ or ‘one spot eartheater’.

It can be distinguished from other members of the genus by possessing a single dark blotch on the flank and a prominent ocellus at the caudal-fin base. Among the named species it is most similar to S. daemon, but that species possesses two blotches on the flank.

The precise extent of this species’ range is unclear. The majority of records pertain to the lower rio Xingu basin in the state of Pará, northern Brazil, including middle and lower reaches of its major tributary the rio Iriri, although the type locality is in Mato Grosso state several hundred kilometres upstream.

There also exist a handful of records from the rio Jamanxim (a major affluent of the rio Tapajós which drain…

This species is also referred to as ‘South American puffer’, ‘SAP’, ‘Amazonian puffer’, ‘Peruvian puffer’, or ‘Brazilian puffer’ in the ornamental trade.

Within the genus Colomesus, C. asellus can be immediately identified by possessing a unique transverse row of dermal flaps across the chin which is absent in its congeners C. psittacus and C. tocantinensis.

This species is relatively rare in the ornamental trade, where it is sometimes confused with its similarly-patterned congeners S. daemon and S. lilith. These three species all possess 1-3 dark blotches on the side of the body and a relatively large ocellus on the upper caudal-fin base, characters that immediately separate them from the remainder of the genus which lack blotches on the body and have a relatively small ocellus on the upper caudal-fin base.

There are at least two variants available one of which is often traded as G.sp. ‘Araguaia orange head’. This is misleading since both are endemic to the Tapajós drainage (see ‘Distribution’), and appears to date back to an error in collection locality when the fish were first exported.

The two differ in the extent of orange colouration on the head which extends onto the opercle in G. sp. ‘orange head (rio Arapiuns form) but is mostly restricted to the area above the ey…

Native to the lower Amazon river basin in Brazil with some populations exhibiting differences in colour pattern to one another, particularly in respect of the degree of red and blue pigmentation on the body and fins.

Type locality is given simply as ‘Amazon River, Brazil’.

Field observations suggest it to display a pref…