Table 1.

Ichnofauna of the Red Crag Formation

IchnotaxonDimensionsLikely tracemakerAbundanceDescriptionLocations
Cylindrichnus isp.W 55 mm; L 225 mmPolychaete30Concentrically lined burrow with conical aperture and heterolithic fill of sandstone, mudstone and shell fragmentsBK, BM, NZ
Diopatrichnus isp.W 12 mm; L 100 mmAnnelid or crustacean15Small subvertical burrow lined obliquely with shell fragmentsBK, CG, NZ
Macaronichnus segregatisW 3 mm; L 25 mmPolychaete>100Small, unbranched subvertical to subhorizontal burrow with heterolithic infill. Occurs in dense patches, frequently cross-cuttingBK, BM, SH, NZ
Polykladichnus irregularisW 13 mm; L 230 mmPolychaete30Y-shaped burrow with a muddy infill. Often in association with SkolithosBM, CG, CH, NF
Psilonichnus upsilonW 60 mm; L 1400 mmCrustacean20Large, occasionally branching subvertical burrow, with spiralling of the sediment laminae surrounding a fine coreBM, NZ
Skolithos linearisW 12 mm; L 180 mmAnnelid or crustacean>100Unlined, unbranched vertical burrow, with a structureless muddy infill. Often in association with PolykladichnusBK, BM, CG, CH, NF, SH, NZ
Teichichnus rectusW 38 mm; L 47 mmAnnelid5Burrow with stacked arcuate spreite composed of mudstoneNZ
Thalassinoides isp.W 33 mm; L 700 mmCrustacean5Complex burrow network with a mudstone infillNZ

Trace fossils are illustrated in Figure 3. Dimensions reported are the mean of examples observed in the study. Likely tracemakers are identified based upon information given by Clifton & Thompson (1978), Humphreys & Balson (1988), Gingras et al. (2008a), Buatois et al. (2017) and Knaust (2018). Abundance reports the approximate number of each ichnotaxon observed across all field locations visited during this study.