Beitrag
Carcinosomatoid eurypterid palaeoecology and phylogeny: ichnology and palaeocommunities
Braddy, Simon J.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen Band 312 Heft 2 (2024), p. 167 - 181
93 Literaturangaben
veröffentlicht: Sep 14, 2024
Online veröffentlicht: Jul 23, 2024
Manuskript akzeptiert: Jun 6, 2024
Manuskript erhalten: Apr 24, 2024
ArtNo. ESP155031202003, Preis: 29.00 €
Abstract
Carcinosomatoidea (Chelicerata: Eurypterida) are regarded as active benthic predators. Megalograptidae, Carcinosomatidae and Mixopteridae have long, spinose raptorial prosomal appendages for capturing and holding prey. Previous models for their mode of life are assessed, based on a review of their trace fossils, functional morphology and a new analysis of their biotic associations. They are here interpreted as slow-swimming, ambush predators and mud grubbers, using their spinose anterior appendages to capture epifaunal and infaunal prey, and their coxal gnathobases and metastoma to process it. Megalograptids tend to associate with, and likely specialised on, invertebrates such as trilobites. Carcinosomatids tend to associate with lightly armoured phyllocarid crustaceans and lingulid brachiopods. Mixopterids tend to associate with more heavily armoured prey, such as thelodonts, osteostracans and pteraspids, although their trackways also indicate a mud-grubbing mode of life. The prosomal appendages (number of podomeres), opisthosomal differentiation and pretelson cercal blades support the hypothesis that megalograptids were more basal than carcinosomatids and mixopterids, which has implications for the (overestimated) diversity of Ordovician eurypterids.
Schlagworte
Arthropoda • Chelicerata • Eurypterida • Palaeozoic • predation