Type locality of Hypostomus robertsoni, Paraná State, Município de Marialva, Upper Paraná River basin, tributary of Ivaí River, Keller River. This Ivaí River basin can be geographically divided into three portions: upper portion with steep slopes ranging from about 1200 to 600 m a.s.l. is a high gradient system; from this section, the median portion goes down to about 400 m a.s.l. having strong to moderate declivities; the lower section is marked by a very low declivity. This species occurs syntopically with H. hermanni in this basin, but while H. hermanni is most frequently captured in the Ivaí River main channel, H. robertsoni commonly occurs either in the Ivaí River and in smaller tributaries (Ref. 124595).

Status of threat: This species is not abundant in scientific collections and does not present a wide distribution in the Upper Paraná River basin. Presently found only in the Ivaí basin, however it is possible that it occurs in adjacent basins and since there are no known imminent threats that would put the species at risk of extinction, this species may be categorized as Least Concern (LC), according to the International Union for Conservation of Nature (IUCN) categories and criteria (IUCN Standards and Petitions Subcommittee, 2019).