PBDB Collection

Hedstroemia Assemblage at Prongs Creek, Yukon Territory (Silurian of Canada)

Where: Yukon, Canada (65.0° N, 136.0° W: paleocoordinates 9.0° N, 47.5° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Road River Formation, Ludlow (427.4 - 423.0 Ma)

• Ludvigsen and Tripp state that age could be earliest Pridoli; their assignment is based on overlying graptolites. Thomas and Lane give age as ?Upper Ludlow.

• bed-level stratigraphic resolution

Environment/lithology: deep subtidal shelf; carbonate

• "Level-bottom carbonate shelf...[Deposits] probably derived from an adjacent carbonate shelf. The brachiopods appear to belong to BA 3, and suggest Janius Community Group affinities."

•SEP: it is clear from the description here that the environment represented by these rocks is a slope or basinal facies. However, the sampled community clearly comes from the outer margin of the platform. Because this is a paleobiological database, I have provided the likely LIFE environment of the assemblage, not the PRESERVATIONAL setting. I have errored on the side of deeper facies

• "The assemblage occurs in a 2 m thick carbonate debris flow..." From ref. 6640: "The debris flows display scoured bases and lack internal grading. They appear to be the products of slumps that swept shells and small (less than 1 cm) limestone clasts off the sides of the adjoining carbonate banks and into the centre of the shale embayment..."

Collection methods: Text includes total counts and percent abundances.

Primary reference: A. T. Thomas and P. D. Lane. 1999. Trilobite assemblages of the North Atlantic Region. in A. J. Boucot and J. D. Lawson, eds. Paleocommunities--a case study from the Silurian and Lower Devonian. Cambridge University Press, Cambrdige 444-457. [M. Foote/M. Foote/M. Foote]more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 23078: authorized by Michael Foote, entered by Michael Foote on 09.07.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names

Conodonta
Prioniodontida -	"Ligonodina elegans" = Oulodus elegans "Ligonodina elegans" = Oulodus elegans Walliser 1964 conodont
Prioniodontida - Prioniodinidae	"Neoprioniodus multiformis" = Idioprioniodus, "Neoprioniodus sp." = Idioprioniodus "Neoprioniodus multiformis" = Idioprioniodus conodont [entered as Neopriooidus multiformis] "Neoprioniodus sp." = Idioprioniodus Gunnell 1933 conodont [entered as Neopriooidus sp.]
Prioniodontida - Balognathidae	Synprioniodina silurica, "Neoprioniodus bicurvatus" = Synprioniodina bicurvata Synprioniodina silurica conodont "Neoprioniodus bicurvatus" = Synprioniodina bicurvata Branson and Mehl 1933 conodont [entered as Neopriooidus bicurvatus]
Panderodontida - Panderodontidae	Panderodus spp. Panderodus spp. Ethington 1959 conodont
Ozarkodinida -	Spathognathodus primus, Ozarkodina media, Hindeodella equidentata, "Plectospathodus sp." = Ozarkodina Spathognathodus primus Branson and Mehl 1933 conodont Ozarkodina media Walliser 1957 conodont Hindeodella equidentata Rhodes 1953 conodont "Plectospathodus sp." = Ozarkodina Branson and Mehl 1933 conodont
-	Spathognathodus sp. Spathognathodus sp. Branson and Mehl 1941 conodont
Strophomenata
Orthotetida - Areostrophiidae	Aesopomum prongsi Aesopomum prongsi
Rhynchonellata
Pentamerida - Parastrophinidae	? Anastrophia sp. ? Anastrophia sp. Hall 1867
Pentamerida - Gypidulidae	Gypidula sp. Gypidula sp. Hall 1867
Spiriferida - Delthyrididae	Delthyris sp., Howellella cf. nucula Delthyris sp. Dalman 1828 Howellella cf. nucula
Spiriferida - Ambocoeliidae	Metaplasia sp. Metaplasia sp.
Athyridida - Meristellidae	? Meristina sp. ? Meristina sp. Hall 1867
Athyridida - Rhynchospirinidae	"? Rhynchospira sp." = Rhynchospirina "? Rhynchospira sp." = Rhynchospirina Schuchert and LeVene 1929
Atrypida - Glassiidae	"Cryptatrypa fahraeusi" = Glassia, "Cryptatrypa ? nalivkini" = Glassia "Cryptatrypa fahraeusi" = Glassia "Cryptatrypa ? nalivkini" = Glassia
Rhynchonellida - Machaerariidae	Ferganella cf. lincolnensis Ferganella cf. lincolnensis
Rhynchonellida - Rhynchotrematidae	Stegerhynchus angaciensis Stegerhynchus angaciensis
Rhynchonellida - Hebetoechiidae	Lanceomyonia brevicostata, Hebetoechia cf. hebe Lanceomyonia brevicostata Hebetoechia cf. hebe
Orthida - Schizophoriidae	Schizophoria cf. fragilis Schizophoria cf. fragilis
Orthida - Draboviidae	Salopina sp. Salopina sp. Boucot 1960
Orthida - Hesperorthidae	? Dolerorthis sp. ? Dolerorthis sp. Schuchert and Cooper 1931
Trilobita
Corynexochida - Styginidae	Paracybantyx asulcatus n. gen. n. sp., Planiscutellum sp. Paracybantyx asulcatus n. gen. n. sp. trilobite Planiscutellum sp. Richter 1956 trilobite genus name in quotes; given by ref. 6640 as "Indeterminate scutelluine"
Proetida - Proetidae	Proetidae indet., Prantlia vagrans n. sp., Hedstroemia kutchini n. sp., Hedstroemia sourdoughi n. sp. Proetidae indet. Salter 1864 trilobite Prantlia vagrans n. sp. Ludvigsen and Tripp 1990 trilobite Hedstroemia kutchini n. sp. Ludvigsen and Tripp 1990 trilobite Hedstroemia sourdoughi n. sp. Ludvigsen and Tripp 1990 trilobite
Phacopida - Encrinuridae	Encrinurinae indet., Balizoma aff. obtusus Encrinurinae indet. Angelin 1854 trilobite Balizoma aff. obtusus trilobite
Lichida - Lichidae	Lichidae indet. Lichidae indet. Hawle and Corda 1847 trilobite