Attached vermiform gastropods in Carboniferous marginal marine stromatolites and biostromes

Abstract

Tubiform fossils conventionally referred to Serpula cf. advena Salter and species of Spirorbis Lamarck from the British Lower Limestone Shales and Border Group (Lower Carboniferous) are re‐examined. They occur in peritidal carbonate environments of schizohaline aspect. These fossils superficially resemble calcareous polychaete tubes but have skeletal characters, including molluscan wall structure, numerous internal septa, and protoconch, which indicate that they represent a new group of substrate‐attached, disjunctly coiled gastropods. They resemble archaeogastropods in internal morphology of the skeleton but show parallels in external form and occurrence with the extant Vermetidae. There are two principal modes of occurrence: (1) erect tubes forming intertidal biostromes associated with non‐skeletal algal laminites, and (2) prostrate discoidal tubes encrusting subtidal skeletal stromatolites or occasionally forming larger irregular bioherms. These biostromes and bioherms are comparable in structure to Recent vermetid reef developments.

Effect of temperature rise and ocean acidification on growth of calcifying tubeworm shells (<i>Spirorbis spirorbis</i>): an in situ benthocosm approach

“…6) that has been reported for Spirorbis spirorbis (Ippolitov and Rzhavsky, 2015) and for many other serpulid species (e.g. Wrigley, 1950;Hedley, 1958;Burchette and Riding, 1977;Weedon, 1994;Buckman, 2015). We observed a complex threedimensional shape of the S. spirorbis chevron lamellae with convex-forward curving layers that show convex-upward curving substructures (Fig.…”

Written in stone: history of serpulid polychaetes through time

“…Regenhardt, 1964;Pillai, 1970;Lommerzheim, 1979;Jäger, 1983;. Burchette and Riding (1977) who analysed microconchid morphology and tube ultrastructure, were the first to justify doubts about their annelid affinities and interpreted them as gastropods. The microconchid microlamellar tube wall ( fig.…”

Corals not serpulids: mineralized colonial fossils in the Lower Jurassic marginal facies of South Wales

“…Although the outer surface of serpulid tubes frequently bears fine striations, internally they lack horizontal or vertical septa. The presence of internal vertical septa in the Pant y Slade specimens and their bifurcation also precludes them being vermetid gastropods (see Burchette & Riding, 1977 for a thorough discussion of the morphology of this group).…”