Lithoxini is a recently described tribe of suckermouth
armored catfishes (Loricariidae) containing
four genera: Avalithoxus, Exastilithoxus, Lithoxus, and
Paralithoxus (Lujan et al., 2018). Each of these genera is
relatively species-poor, with one species each in Avalithoxus
and Lithoxus, two in Exastilithoxus (excluding several known
but undescribed species), and eight in Paralithoxus (excluding
several undescribed; Eschmeyer et al., 2018). All species of
Lithoxini are small (,65 mm SL) and dorsoventrally
flattened (.7.2 times in standard length). Unlike most other
members of the Hypostominae, members of the Lithoxini are
primarily invertivores, although seeds were present in the gut
of the Avalithoxus examined here. The stomach is enlarged in
Lithoxus and Paralithoxus, and they are thought capable of
breathing air (Armbruster, 1998). Given their small size, how
dorsoventrally flattened they are, and the large size of their
eggs, female Lithoxus typically carry only a few ripe eggs in
each ovary (Armbruster, 1998).
Armbruster, Greene and Lujan, Copeia 106, No. 4, 2018, 671–680
