ASGP (2015), vol. 85: 433–444
ECDYSICHNIA – A NEW ETHOLOGICAL CATEGORY FOR TRACE FOSSILS PRODUCED BY MOULTING
Lothar H. VALLON (1), Günter SCHWEIGERT (2), Richard G. BROMLEY (3), Martin RÖPER (4) & Martin EBERT (5)
1) Geomuseum Faxe (Østsjællands Museum), Østervej 2, DK-4640 Faxe, Denmark; email: kv at oesm.dk
2) Staatliches Museum für Naturkunde, Rosenstein 1, D-70191 Stuttgart, Germany; e-mail: guenter.schweigert at smns-bw.de
3) Rønnevej 97, DK-3720 Aakirkeby, Denmark; e-mail: richard at bromley.dk
4) Bürgermeister-Müller-Museum Solnhofen, Bahnhofstr. 8, D-91807 Solnhofen, Germany; e-mail: m.roeper at solnhofen.de
5) Jura-Museum Eichstätt, Willibaldsburg, D-85072 Eichstätt, Germany; e-mail: martin.ebert at jura-museum.de
Vallon, L. H., Schweigert, G., Bromley, R. G., Röper, M. & Ebert, M., 2015. Ecdysichnia – a new ethological category for trace fossils produced by moulting. Annales Societatis Geologorum Poloniae, 85: 433–444.
Abstract: The shedding of exoskeletons is an important aspect of the lifecycle of some in vertebrates (mainly arthropods). To rid them selves of the old cuticula (= exuvia), these animals of ten have to thrash about, twist around or rub themselves against the sediment or other more or less solid objects. In softgrounds, this behaviour may create distinctive patterns that have to be regarded as trace fossils. Accordingly, some ichnospecies of Rusophycus have recently been interpreted as traces made during ecdysis. Most of the so-called “Schwoimarken” from the Solnhofen lithographic limestones (Upper Jurassic, SE Germany), usually interpreted as structures made by dead organisms swaying in response to water movements, must be understood as traces of arthropod ecdysis. In this context, we erect Harpichnus bartheli igen. et isp. nov. and propose the new ethological category, ecdysichnia, for moulting traces. In most “Schwoimarken” containing body-fossil remains other than arthropods, we see sediment displacement by scavenging arthropods rather than mortichnia (sensu Seilacher, 2007). We further propose inclusion of the recently erected category pupichnia for pupation chambers as a subcategory of ecdysichnia. In our opinion, pupation is a special form of moulting that does not justify the splitting of categories, as briefly noted by Vallon et al. (2013).
Manuscrip treceived 14 October 2014, accepted 10 May 2015
