Problematica can be:
* A substitute for a taxon, used for organisms whose classification cannot be decided: See ''
incertae sedis''
* The second part of the
binomial name
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
of various species
{{Disambig