'guianensis' originates from New Latin (Neo-Latin), specifically from the place-name 'Guiana' (from Spanish/Portuguese 'Guayana'/'Guiana'), where the toponym referred to the Guiana region of northeastern South America (itself likely derived from an indigenous word meaning 'land of many waters' or 'riverland').

'guianensis' was formed by Latinizing the geographic name 'Guiana' into an adjectival species epithet (the suffix '-ensis' in Latin denotes 'originating in' or 'coming from'), and it has been used in scientific nomenclature since modern taxonomic practice adopted Neo-Latin forms.

Initially, the element referred specifically to the place 'Guiana'; over time it has retained that core meaning and is now conventionally used as an adjectival epithet meaning 'from Guiana' in species names.