Balnibarbi erugata Fortey, 1974: 31, pl. 5, fig. 1-10.
HOLOTYPE: Cranidium, PMO NF 3016 (figured in Fortey, 1974: pl. 5, fig. 1-3).
TYPE LOCALITY: Profilstranda, Olenidsletta Member, Valhallfonna Formation, Ny Friesland, Spitsbergen, Svalbard.
STRATIGRAPHIC RANGE: Throughout trilobite zone V 1c and the very beginning of V 2a (Fortey, 1980). These zones coincide with the upper Oepikodus evae and lower Oepikodus intermedius conodont zones, and the Didymographtus protobifidus graptolite zone within the upper Floian (fig. 1; see also Kröger et al., 2017).
DIAGNOSIS: Balnibarbi erugata subspecies with relatively short (sag.) preglabellar field (<0.35 length of glabella) and fine granulation present on glabella, axial, palpebral, and posterior border furrows, and on frontal area adjacent to anterior border furrow.