A new Early Devonian spinose phacopid trilobite from Limekilns, New South Wales: morphology, affinities, taphonomy and palaeoenvironment

Wright, Anthony J; Haas, Winfried

doi:10.3853/j.0067-1975.42.1990.111

Cited by 6 publications

(11 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…crawfordae , and E . serratus (see Wright and Haas, 1990; Ramsköld and Werdelin, 1991; Ebach, 2002; Rustán et al, 2011a, 2011b). The actual taxonomic concept of Echidnops highlights the relevance of postcephalic characters in phacopid systematic, as was already stated by Sandford (2002).…”

Section: Systematic Paleontologymentioning

confidence: 99%

See 1 more Smart Citation

The phacopid trilobiteEchidnops taphomimusn. sp. from the Lower Devonian of Argentina: insights into infaunal molting, eye architecture and geographic distribution

Rustán

Balseiro²

2016

J. Paleontol.

View full text Add to dashboard Cite

Some Silurian-Devonian Argentinian trilobites characterized by infaunal behavior during molting are considered. After a taxonomic reappraisal, a species previously referred to a lineage of the phacopidPaciphacopsis proposed asEchidnops taphomimusnew species, from the Lower Devonian (probably late Lochkovian) of the Talacasto Formation, Argentine Precordillera. The visual surface ofE.taphomimusindicates that a irregular pattern of lens arrangement, typical of early phacopids such as the OrdovicianOrmathops, can also be recognized in more derived Devonian relatives, providing new insights on some evolutionary aspects of visual development.Echidnopsis recognized in Australia and Argentina, recording an unusual distribution pattern in trilobites from the Lower Devonian of southern South America, otherwise mostly linked to faunas of related Gondwanan, austral circum-polar Devonian basins of the Malvinokaffric Realm. In accordance with proposed increasing predation pressure in the context of the Mid Paleozoic Marine Revolution, evidence indicates that the infaunal molting behavior, as defensive strategy, arose in several trilobite groups during Silurian-Devonian times, rather than in a single endemic lineage ofPaciphacopsspecies.

show abstract

Section: Systematic Paleontologymentioning

confidence: 99%

“…Rustán et al (2011a) discussed E . crawfordae (Wright and Haas, 1990) from the late Pragian Rosedale Shale, New South Wales, Australia, as the most closely related species to E . taphomimus n. sp..…”

Section: Systematic Paleontologymentioning

confidence: 99%

The phacopid trilobiteEchidnops taphomimusn. sp. from the Lower Devonian of Argentina: insights into infaunal molting, eye architecture and geographic distribution

Rustán

Balseiro²

2016

J. Paleontol.

View full text Add to dashboard Cite

show abstract

“…The aim was also to test the structural and stratigraphic reinterpretation of the Limekilns sequence, by determining if the volcaniclastic unit is the same age as samples of the Merrions Formation collected from the type section. The Limekilns Formation ranges up to late Emsian in age ( Wright & Chatterton 1988; Wright & Haas 1990). If the volcaniclastic ‘Winburn Tuff’ sequence overlies the Limekilns Formation as originally interpreted by Packham (1968), it will be significantly younger than the ages obtained for the type section of the Merrions Formation.…”

Section: Sample Selectionmentioning

confidence: 99%

“…(2) Fossils are scattered at different levels in the basal unit of the Limekilns Formation (formerly the ‘Rosedale Shale’ of Packham 1968), which conformably overlies the Merrions Formation. The basal shales yield a mostly pelagic fauna, comprising graptolites, tentaculitids, hyolithids and conulariids, and plant fragments ( Wright & Haas 1990). Benthic faunas comprising mostly brachiopods with some corals, rare bivalves and trilobites, are also present.…”

Section: Regional Biostratigraphymentioning

confidence: 99%

“…Benthic faunas comprising mostly brachiopods with some corals, rare bivalves and trilobites, are also present. The occurrence of the tentaculitid (dacryocanarid) Nowakia acuaria , a well‐known Pragian index fossil ( Wright & Haas 1990), indicates a Pragian to early Emsian age for the base of the Limekilns Formation ( Lütke 1979).…”

Section: Regional Biostratigraphymentioning

confidence: 99%

See 1 more Smart Citation

U–Pb dating of silicic lavas, sills and syneruptive resedimented volcaniclastic deposits of the Lower Devonian Crudine Group, Hill End Trough, New South Wales

Jagodzinski

Black

1999

Australian Journal of Earth Sciences

View full text Add to dashboard Cite

The Hill End Trough of central‐western New South Wales was an elongate deep marine basin that existed in the Lachlan Fold Belt from the early Late Silurian to late Early Devonian. It is represented by a regionally extensive, unfossiliferous sequence of interbedded turbidites and hemipelagites of substantially silicic volcanic derivation, which passes laterally into contemporaneous shallow‐water sedimentary rocks. The Turondale and Merrions Formations of the Lower Devonian Crudine Group are two prominent volcanogenic formations in the predominantly sedimentary trough sequence. They contain a range of primary and resedimented volcanic facies suitable for U–Pb dating. These include widespread subaqueous silicic lavas and/or lava cryptodomes, and thick sequences of crystal‐rich volcaniclastic sandstone emplaced by a succession of mass‐flows that were generated by interaction between contemporaneous subaerial pyroclastic flows and the sea. Ion microprobe dating of the two volcanogenic formations by means of the commonly used SL 13 zircon standard yields ages ranging between 411.3 ± 5.1 and 404.8 ± 4.8 Ma. Normalising the data against a different zircon standard (QGNG) yields preferred slightly older mean ages that range between 413.4 ± 6.6 and 407.1 ± 6.9 Ma. These ages broadly approximate the Early Devonian age that has been historically associated with the Crudine Group. However, the biostratigraphically inferred late Lochkovian – early Emsian (mid‐Early Devonian) age for the Merrions Formation is inconsistent with the current Australian Phanerozoic Timescale, which assigns an age of 410 Ma to the Silurian–Devonian boundary, and ages of 404.5 Ma and 395.5 Ma to the base and top of the Pragian, respectively. There is, however, good agreement if the new ages are compared with the most recently published revision of the Devonian time‐scale. This suggests that the Early Devonian stage boundaries of the Australian Phanerozoic Timescale need to be revised downward. The new ages for the Merrions Formation could also provide a time point on this time‐scale for the Pragian to early Emsian, for which no data are presently available.

show abstract

Late Silurian and Early Devonian biostratigraphy in the Hill End Trough and the Limekilns area, New South Wales

Packham

Percival

Rickards

et al. 2001

Alcheringa: An Australasian Journal of Palaeontology

View full text Add to dashboard Cite

A new Early Devonian spinose phacopid trilobite from Limekilns, New South Wales: morphology, affinities, taphonomy and palaeoenvironment

Cited by 6 publications

References 15 publications

The phacopid trilobiteEchidnops taphomimusn. sp. from the Lower Devonian of Argentina: insights into infaunal molting, eye architecture and geographic distribution

The phacopid trilobiteEchidnops taphomimusn. sp. from the Lower Devonian of Argentina: insights into infaunal molting, eye architecture and geographic distribution

U–Pb dating of silicic lavas, sills and syneruptive resedimented volcaniclastic deposits of the Lower Devonian Crudine Group, Hill End Trough, New South Wales

Late Silurian and Early Devonian biostratigraphy in the Hill End Trough and the Limekilns area, New South Wales

Contact Info

Product

Resources

About