The lichen was formally described as a new species in by lichenologists Bibiana Moncada and Robert Lücking.The type specimen was collected in the Parque Ecológico Matarredonda (El Verjón, Cundinamarca) at an altitude of 3,220 m (10,560 ft).

The species epithet refers to its resemblance to Sticta humboldtii, but with the added Greek prefix "pseudo," meaning "false."

This is because, unlike the similarly named S. parahumboldtii, S. pseudohumboldtii is not the closest relative to S. humboldtii.

It has been recorded in subandine forests and páramo vegetation at elevations ranging from 1,900 to 3,975 m (6,234 to 13,041 ft).

Sticta pseudohumboldtii is commonly associated with Metzgeria spp., Heterodermia circinalis, Leptogium spp., and Oropogon bicolor.