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Guide to Encyonema pergracile

Krammer 1997

Encyonema Pergracile Guide
Credit: Sarah Spaulding, Ian Bishop
  1. Valves elongate
  2. Isolated punctum present
  3. Apices narrow, acute
  4. Terminal fissures long

Valves are elongate, linear-lanceolate and dorsiventral. The apices are narrow and acute. The apices may be ventrally deflected in larger valves. The distal raphe has long terminal fissures. The axial area is linear and slightly expanded at the central area. An isolated punctum is present on the dorsal side of the central area, in line with a central stria. Near the apices, the striae on the ventral side of the valve are convergent, and greater in stria density.