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Abstract The extraordinary window of phosphatized and phosphatic small shelly fossils (SSF) during the early and middle Cambrian is an important testament to the radiation of biomineralizing metazoans. WhileSSFare well known from most Cambrian palaeocontinents during this time interval, western Laurentia has relatively fewSSFfaunas. Here we describe a diverseSSFfauna from the early Cambrian (Stages 3–4) Mural Formation at three localities in Alberta and British Columbia, Canada, complemented by carbon isotope measurements to aid in a potential future bio‐chemostratigraphic framework. The fauna expands the recordedSSFassemblage diversity in western Laurentia and includes several brachiopods, four bradoriids, three chancelloriids, two hyoliths, a tommotiid and a helcionellid mollusc as well as echinoderm ossicles and specimens ofMicrodictyon,VolborthellaandHyolithellus. New taxa include the tommotiid genusCanadiellagen. nov., the new bradoriid speciesHipponicharion perforatasp. nov. andPseudobeyrichona tauratasp. nov. Compared with contemporaneous faunas from western Laurentia, the fauna is relatively diverse, particularly in taxa with originally phosphatic shells, which appear to be associated with archaeocyathid build‐ups. This suggests that the generally low faunal diversity in western Laurentia may be at least partly a consequence of poor sampling of suitable archaeocyathan reef environments. In addition, the tommotiidCanadiella filigranaappears to be of biostratigraphical significance in Cambrian Stage 3 strata of western Laurentia, and the unexpected high diversity of bradoriid arthropods in the fauna also suggests that this group may prove useful for biostratigraphical resolution in the region.
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Molecular diversity of Diplura in southern High Appalachian leaf litter
The fauna of Diplura, the two-pronged bristletails (Hexapoda), of the southern Appalachians has received little focused systematic attention. Existing literature suggests the fauna to comprise around a dozen species. Based on a broader DNA barcode-based survey of high elevation litter arthropods in the region, we suggest the fauna to be much richer, with automated species delimitation methods hypothesising as many as 35 species, most highly restricted to single or closely proximate localities. Such a result should not be very surprising for such small, flightless arthropods, although it remains to be seen if other markers or morphology support such high diversity. The region still remains sparsely sampled for these more cryptic elements of the arthropod fauna and much larger numbers of species undoubtedly remain to be discovered.
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- Award ID(s):
- 1916263
- PAR ID:
- 10512091
- Publisher / Repository:
- Pensoft
- Date Published:
- Journal Name:
- Biodiversity Data Journal
- Volume:
- 12
- Issue:
- 3125162
- ISSN:
- 1314-2836
- Page Range / eLocation ID:
- 1-13
- Subject(s) / Keyword(s):
- Diplura Hexapoda soil biodiversity megabarcoding Appalachia species delimitation genetic distance COI
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3897/BDJ.12.e125162
