Diagnosis.—Galleries bent in a long, narrow U-form with the inward-facing walls of the limbs fused by complete removal; the original position of the median wall is sometimes indicated by a very shallow axial depression along the structure. Vane absent. Transverse section always flattened-elliptical but showing gradual decrease in width toward the aperture. Shape of aperture flattened-oval (cited from Bromley and D’Alessandro 1983)

Remarks.—Bromley and D’Alessandro (1983) observed broader specimens, which are at least 2 mm wide and never show interpenetration. However, the characteristic distal widening is diagnostic of this ichnospecies. Originally, this ichnospecies was described by Voigt (1971) as Dodecaceria cretacea. Later, it was transferred to Trypanites by Bromley (1972) and finally to Caulostrepsis by Bromley and D’Alessandro (1983). Voigt (1971) and Bromley and D’Alessandro (1983) regarded it as having been produced by the cirratulid polychaete Dodecacería concharum Örsted, 1843, but Gibson (2016) who examined the material studied by the aforementioned author and compared it with recent borings of this polychaete, questioned this view and suggested that Caulostrepsis cretacea is similar to the borings of Polydora.