Boreozonacola Guide
Credit: Ditmar Metzeltin
  1. Valves linear, often with triundulate margins
  2. Areolae coarse
  3. Central area oval to round

Valves of Boreozonacola are linear, often with tumid central and subapical margins. The raphe is lateral. The proximal raphe ends are simple, curving to the primary side of the valve. The distal raphe ends curve to the secondary side of the valve. The axial area is narrow and linear. The central area is round. Striae are radiate and are composed of coarse areolae. Voight discontinuities are often present.

The genus Boreozonacola is named for the boreal zones of Eurasia and North America for which species in this genus are found. Taxa include the former Navicula pseudosilicula var. olympica Sovereign (as Boreozonacola olympica (Sovereign) Lange-Bertalot et al.), Navicula pseudosilicula Hustedt (Boreozonacola hustedtii Lange-Bertalot, Kulikovskiy & Witkowski) and Navicula lacuna Patrick & Freese (as Boreozonacola lacuna (Patrick & Freese) Lange-Bertalot, Kulikovskiy & Witkowski).