Nystalea phildevriesi is morphologically similar to N. clotho Thiaucourt, 2003, whose type locality is Olancha, Honduras at 1500 m altitude (Thiaucourt, 2003). The male genitalia of Nystalea phildevriesi have the costula wide and triangular at the base, thin, and flattened towards apex. Nystalea clotho is not present in Costa Rica.