ASGP (2018), vol. 88: 291–301
SCLEROBIONTS ON ORGANIC SUBSTRATES FROM THE LATE PALEOCENE CHEHEL-KAMAN FORMATION, KOPET-DAGH BASIN, NE IRAN
Amir SALAHI (1), Magdy EL-HEDENY (2), Olev VINN (3) & Mohamed RASHWAN (4)
1) Department of Geology, Ferdowsi University of Mashhad, Mashhad, Iran; e-mail: amir.salahi@mail.um.ac.ir
2) Department of Geology, Faculty of Science, Alexandria University, Alexandria 21568, Egypt; e-mail: magdy.elhedeny@alexu.edu.eg
3) Department of Geology, University of Tartu, Ravila 14A, 50411 Tartu, Estonia; e-mail: olev.vinn@ut.ee
4) Department of Biological and Geological Sciences, Faculty of Education, Alexandria University, Alexandria 14037, Egypt; e-mail: rashwan.m.a@alexu.edu.eg
Salahi, A., El-Hedeny, M., Vinn, O. & Rashwan, M., 2018. Sclerobionts on organic substrates from the Late Paleocene Chehel-Kaman Formation, Kopet-Dagh Basin, NE Iran. Annales Societatis Geologorum Poloniae, 88: 291 –301.
Abstract: Molluscs (oysters and gastropods) of the Late Paleocene Chehel-Kaman Formation, Kopet-Dagh Basin, NE Iran were significantly colonized by sclerobionts. The largest area of the shells studied is covered by various borings. The diversity of macro-bioeroding ichnotaxa is rather high, including Gastrochaenolites Leymerie, 1842; Maeandropolydora Voigt, 1965; Trypanites Mägdefrau, 1932; Talpina von Hagenow, 1840, and possibly Entobia Bronn, 1837. Some slightly conical borings penetrating the shells could belong to predatory tracemakers of Oichnus Bromley, 1981. Encrusters include calcareous polychaetes, cyclostome and cheilostome bryozoans, foraminifera and oysters. Calcareous sabellids [i.e. Glomerula serpentina (Goldfuss, 1831)] and serpulids are equally common sclerobionts in the association. Bryozoans cover a slightly larger area of the substrate than the calcareous polychaetes, while encrusting oysters are subordinate. The majority of fossils in the hard-substrate community studied belong to suspension feeders. Sclerobionts are typical of the shallow-marine environment, commonly in warm water. The present study is the first attempt to record the occurrence and diversity of epi- and endobionts in the organic substrates, present in the topmost part of the Late Paleocene Chehel-Kaman Formation, Kopet-Dagh Basin, NE Iran.
Manuscript received 3 October 2018, accepted 10 December 2018
