Lepidocoleidae Clarke, 1896

Gügel, Benjamin, Baets, Kenneth De, Jerjen, Iwan, Schuetz, Philipp & Klug, Christian, 2017, A new subdisarticulated machaeridian from the Middle Devonian of China: Insights into taphonomy and taxonomy using X-ray microtomography and 3 D-analysis, Acta Palaeontologica Polonica 62 (2), pp. 237-247 : 241-242

Family Lepidocoleidae Clarke, 1896 Genus Lepidocoleus Faber, 1886

Type species: Lepidocoleus jamesi ( Hall and Whitfield, 1875) , Cincinnatian ( Upper Ordovician) of Ohio, USA .

Remarks.—The presence of a tongue-and-groove hinge, the absence of additional rows of sclerites, sclerite form, thickness and the presence of a dorsal groove corroborate the assignment of the here described material as Lepidocoleidae . It is worth stressing that this sclerite assemblage does not contain any obvious anterior outer sclerites as recognized in plumulitids ( Vinther and Rudkin 2010) and possibly turrilepadids ( Adrain et al. 1991) as they are never seen in lepidocoleids (so far at least). Furthermore, we did not find evidence for the presence of outer sclerites at all suggesting that we are dealing with a derived lepidocoleid ( Parry et al. 2014). Unfortunately, muscle attachment structures cannot be distinguished with our scan-resolution. However, the shape of the rugae is consistent with the genus Lepidocoleus known from the Early Ordovician until the Givetian (Devonian).

In Fig. 9 , we list species included in Lepidocoleus according to their relative age with some important characters and their occurrence. Devonian forms are listed at the bottom. Note that the here described specimen appears to be one of the youngest representatives of the genus. We did not include Aulakolepos elongatum Dzik, 1994 and Plicacoleus robustus Dzik, 1986 which might also belong to Lepidocoleus , but for the moment are still assigned to different genera pending a proper revision of the genus which falls outside the scope of our study.

Stratigraphic and geographic range.—Ordovician to Middle Devonian of northern America, Europe, southeast Asia, and northern Africa.

Figures

Fig. 9. Comparison between the known species of Lepidocoleus and L. kuangguoduni sp. nov. with number of sclerites, age, and geographic occurrence indicated; lateral (A) and dorsal (E) views of the fossils, images of sclerites (B), outlines of sclerites (C), cross sections, to show the proportions of the dorsal depression (D).