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Guide to Navicymbula pusilla

(Grunow in A.Schmidt) Krammer 2003

Navicymbula Pusilla Guide
Credit: Marina Potapova
  1. Valves dorsiventral
  2. Valves 4.2-5.9 μm wide
  3. Central area small, lanceolate
  4. Terminal raphe fissures turned to dorsal side
  5. External proximal raphe ends turned to dorsal side

Valves are moderately dorsiventral, with arched dorsal margin and flat, or slightly convex, ventral margin. The axial area is narrow; it widens in the valve center to form a small lanceolate central area. The raphe is straight and weakly lateral, with external proximal ends and terminal fissures hooked to the dorsal side. Striae are radiate in the valve center, becoming convergent at the ends.