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Guide to Ulnaria contracta

(Østrup) E.Morales and M.L.Vis 2007

Ulnaria Contracta Guide
Credit: Ian Bishop
  1. Slightly constricted mid-valve
  2. Apices rostrate to subcapitate
  3. Ghost striae present
  4. Two rimoportula present on each valve

Valves are elongate and linear, with a slightly constricted central area. Apices are rostrate to sub-capitate, and rounded to truncated. The central area is rectangular and contains "ghost" striae. Each valve has two rimoportula, with one at each apex.