Most of the gastros seem to come in mixed shipments, but I think its been well established now that they are different species.
There was a time when
scitilus and
ctenocephalus where thought to be variations of the same species.
If you look at the species together you will see that
scitilus and
ctenocephalus share similar characteristics (body and head shape, etc) since they are part of the
ctenocephalus group.
Stellatus and
zebrinus share similar characteristics since they are part of the
ridens group.
Ocellatus is the odd man out here being a part of its own group with the similar
farragus.
In the wild, they don't all occur in the same streams.
Ocellatus occurs with
ctenocephalus and
stellatus, while
zebrinus occurs in some streams with
ctenocephalus.
Scitilus occurs in different watersheds but they are near locations that have
ctenocephalus. It also occurs with
farragus which we may be mistaking for
ocellatus.
All this info comes from Dr. Tan's great book
The Borneo Suckers .
And, no, that's not a threadfin.
Keep guessing.
