Physopyxis lyra is a member of the family Doradidae, a South
American catfish family that is easily recognized by the
presence of spiny bony plates along the lateral line. The genus
Physopyxis included just a single species, P. lyra, until Sousa
and Rapp Py-Daniel(2005) redescribed this species and described
two new species in 2005. This is is a tiny catfish, with adults
not known to exceed 31 mm standard length (i.e., excluding
tail). Physopyxis lyra differs from the other species of the
genus by possessing a single row of spines on the lateral plates
and a strong scapular girdle with long, broad coracoid processes
having distal tips enlarged and divergent. This species is known
from the rio Ampyiacu (and lowland portions of other tributaries
to the upper Amazon in northeastern Peru) to the rio Uatumã, a
left bank tributary to the Amazon in eastern Amazonas State,
Brazil. No reliable records exist for the rio Negro basin. (
Sousa and Rapp Py-Daniel 2005) Physopyxis lyra are usually found
in sites with accumu