Exceptionally rich and well-preserved silicified exuviae comprising numerous immature growth stages allow the tracing of detailed morphological and morphogenetical features of the reduced-eyed phacopid species Cryphops? ensae (Richter and Richter, 1926) from the latest Famennian of Thuringia (Central Germany). Ontogenetic features of this species are more similar to those of Phacops than to Trimerocephalus.