Scolicia

Villegas-Martín, Jorge, Netto, Renata G., Rojas-Consuegra, Reinaldo & de Gibert, Jordi M., 2025, Paleoecology and taphonomy of spatangoid echinoid-produced burrows (Scolicia) in slope and basin floor deposits from the Eocene of Cuba, Palaeontologia Electronica (a 4) 28 (1), pp. 1-17 : 8-9

THE EOCENE SCOLICIA TRACEMAKER

Natural observations and experiments in aquaria demonstrated that the ichnogenus Scolicia (as the morphologies described herein) corresponds to the burrows resulted from the grazing activity of spantagoid echinoids with double drainage tubes (e.g., Ward and Lewis, 1975; Howard et al., 1974; Bromley and Asgaard, 1975; Smith and Crimes, 1983; Bromley et al., 1997; Belaústegui et al., 2017). These large meniscate traces are typically produced by backfilling when the spatangoid plows through the sediment ( Smith and Crimes, 1983; Kanazawa, 1992, 1995; Bromley et al., 1997). The animal excavates the sediment in the front, which is transported to the posterior part of the burrow, where it is packed with mucus. The open burrow is limited to the volume immediately surrounding the echinoid test. The two open drains (related to sediment strings) are kept behind by action of the subanal tuft spines and the corresponding tube feet, while periodically, a respiratory shaft may be constructed for aeration purposes or to feed upon surface detritus ( Smith and Crimes, 1983; Plaziat and Mahmoudi, 1988; Kanazawa, 1992, 1995; Bromley et al., 1997).

It is well-known that many echinoids from different fossil and extant families of the Order Spantangoida possess the morphology to produce Scolicia -like burrows (e.g., Bromley and Asgaard, 1975, Bromley et al., 1995, 1997; Kanazawa, 1995; Asgaard and Bromley, 2007). Fossil species of different families, such as Schizasteridae ( Brisaster iheringi ) and Hemiasteridae ( Hemiaster expergitus ), were observed within or associated with Scolicia traces ( Fu and Werner, 2000; Carmona et al., 2020).

The fossil record of spatangoid in Cuba is extensive and includes specimens of different families, including the Schizasteridae and Hemiasteridae families. In addition, genera such as Hemiaster , Schizaster , and Linthia have been identified in Eocene deposits (e.g., Sanchez Roig, 1926, 1949; Kier, 1984). Thus, these taxa might be potential tracemakers of the Scolicia specimens studied herein. However, no body fossil of spatangoid echinoids were reported in the studied sections bearing Scolicia , although undetermined fragments of echinoids are known in the marine deposits of the Capdevila Formation ( Brust et al., 2011). Therefore, further detailed studies on the echinoderms found in the Capdevila Formation are necessary to try to infer the Scolicia tracemakers more accurately.