New exceptionally preserved panarthropods from the Drumian Wheeler Konservat‐Lagerstätte of the House Range of Utah

Abstract

The Drumian Wheeler Konservat-Lagerst€ atte of the House Range of Utah (Wheeler-HR) has yielded one of the most diverse exceptionally preserved Cambrian biotas of North America. The discovery of soft-bodied fossils invariably provides precious insights into this biota, given that most of its non-biomineralizing components are known from very few specimens. This contribution describes some 30 new exceptionally preserved fossils of Wheeler panarthropods. Two new species are recognized, the radiodont Hurdia sp. nov. A and the megacheiran Kanoshoia rectifrons gen. et sp. nov. Along with a species of Leanchoilia, K. rectifrons represents the first confident megacheiran record in these strata. The presence of the radiodont genus Amplectobelua and the isoxyid species Isoxys longissimus is reported outside of the Burgess Shale in Laurentia. New specimens of Caryosyntrips serratus, Naraoia compacta, Messorocaris magna and Mollisonia symmetrica provide insights into the phylogenetic affinities, local spatial distribution and morphological variation of these species hitherto known by single specimens in the Wheeler-HR. The same is true of new materials of the more common Pahvantia hastata and Perspicaris? dilatus. Formal descriptions of the order Mollisoniida ord. nov. and family Mollisoniidae fam. nov. are also provided. Last, the preservation of body structures other than the dorsal exoskeletons is illustrated for the first time in two common components of the fauna: the agnostid Itagnostus interstrictus and the bivalved euarthropod Pseudoarctolepis sharpi. The new material substantially improves our understanding of the diversity of the Wheeler-HR biota, and provides new evidence of its distinctiveness relative to the Wheeler biota of the Drum Mountains.

The diverse radiodont fauna from the Marjum Formation of Utah, USA (Cambrian: Drumian)

“…This enabled us to exclude the taxa that only occur in stratigraphic intervals barren of non-biomineralized fossils, such as the lower and upper parts of the Marjum Formation or the lower part of the Weeks Formation. We then updated the resulting dataset to include omitted ( Caron, Conway Morris & Cameron, 2013 ) or more recently published contributions ( Conway Morris et al, 2015 ; Maletz & Steiner, 2015 ; Smith, 2015 ; Foster & Gaines, 2016 ; Pates, Daley & Ortega-Hernández, 2017 ; Lerosey-Aubril & Pates, 2018 ; Lerosey-Aubril & Skabelund, 2018 ; Lerosey-Aubril et al, 2018 , 2020 ; Pates, Daley & Lieberman, 2018 ; Pates, Daley & Ortega-Hernández, 2018 ; Conway Morris et al, 2020 ; Lerosey-Aubril, Skabelund & Ortega-Hernández, 2020 ) and some new discoveries (R. Lerosey-Aubril, 2019, personal observation). Finally, we complemented the database with information on lifestyle for each taxon.…”

“…Recent studies in Utah, the home of five Cambrian Konservat-Lagerstätten ( Robison, Babcock & Gunther, 2015 ), have increased the known diversity of the radiodont faunas in the Spence Shale (three genera; Briggs et al, 2008 ; Pates & Daley, 2017 ; Pates, Daley & Lieberman, 2018 ), the Wheeler Formation in the Drum Mountains (three genera; Halgedahl et al, 2009 , fig. 10L; Pates & Daley, 2017 ; Lerosey-Aubril & Pates, 2018 ), and especially the Wheeler Formation in the House Range (at least six genera; Briggs et al, 2008 ; Pates, Daley & Ortega-Hernández, 2017 , 2018 ; Lerosey-Aubril & Pates, 2018 ; Pates, Daley & Lieberman, 2018 ; Lerosey-Aubril et al, 2020 ). Only one radiodont genus ( Anomalocaris ) has as-yet been reported from the Weeks Formation ( Lerosey-Aubril et al, 2014 ), but this is the least explored and the youngest of the Cambrian Konservat-Lagerstätten of Utah ( Lerosey-Aubril et al, 2018 ).…”

Occurrence of the eudemersal radiodontCambrorasterin the early Cambrian Chengjiang Lagerstätte and the diversity of hurdiid ecomorphotypes

“…Pates & Daley, 2017; Cong et al 2018; Zeng et al 2018; Guo et al 2019; Moysiuk & Caron, 2019; Pates et al 2019, in press). Recent studies have shown that most exceptionally-preserved Cambrian biotas contain more than one representative of the group (Daley & Budd, 2010; Lerosey-Aubril et al 2014; Pates et al 2018; Pates & Daley, 2019; Lerosey-Aubril et al in press; Pates et al in press), and typically members of two or more of the four families of radiodonts. All of this is clear evidence that radiodonts, like many metazoan groups at that time, underwent a major adaptive radiation during the Cambrian period (e.g.…”

Injured trilobites within a collection of dinosaurs: Using the Royal Tyrrell Museum of Palaeontology to document Cambrian predation

“…Recent studies of other radiodont groups has highlighted the presence of taxa with gnathobasic-like structures on frontal appendages, which may have also been in used in predation (Cong et al, 2017(Cong et al, , 2018. While such morphologies are not known from North American deposits, related taxa are known from the Stage 4 Kinzers Formation and Latham Shale (USA), Wuliuan Burgess Shale (Canada), and Drumian Wheeler Formation (Daley and Budd, 2010;Lerosey-Aubril et al, 2020). Finally, the raptorial frontal appendages of stem chelicerate Yohoia tenuis Walcott, 1912, may have functioned like a hammer and been capable of breaking biomineralised exoskeletons, in a manner comparable to stomatopods (Pratt, 1998;Haug et al, 2012;Bicknell and Paterson, 2018).…”