The Early Devonian (Emsian) acrotretid microbrachiopod Opsiconidion minor Popov, 1981, from the Alaska/Yukon Territory border and Novaya Zemlya

Two species of Early Devonian graptolites are described from the Richardson Mountains, northern Yukon Territory; these are ?Pristiograptus sp. and Monograptus fanicus Koren', the latter being reported for the first time from the northern Canadian Cordillera. Associated grapto lites as well as the presence of M. fanicus indicate a Pragian age. The presence of M. fanicus helps fill the zonal gap between the late Lochkovian hercyniens Zone, and probable late Pragian thomasi and yukonensis Zones, and suggests that lower and upper Pragian substage divisions are possibly recognizable in the graptoiite facies.

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New data on Late Silurian and Early Devonian brachiopods from the Royal Greek area, Yukon Territory

Canadian Journal of Earth Sciences ◽

10.1139/e82-028 ◽

1982 ◽

Vol 19 (2) ◽

pp. 364-375 ◽

Cited By ~ 16

Author(s):

Alfred C. Lenz

Keyword(s):

Yukon Territory ◽

Early Devonian

Late Silurian and Early Devonian brachiopod species are listed from two new sections in the Royal Creek area, Yukon. The data from these sections fill in knowledge of the biostratigraphy of brachiopods of Late Silurian (Ludlovian and Pridolian) and, more importantly, of early Zlichovian (late Early Devonian) ages, of the northern Cordillera.Thirteen species of brachiopods are described in this study, five (none new) from the Late Silurian, and eight from the early Zlichovian (late Early Devonian), of which species of Phragmostrophia, Linguopugnoides, Vagrania, ?Salairina, and Metaplasia are probably new, but have not been given formal species names.

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Semitubina yukonensis new species, first occurrence of this biogeographically distinctive Old World Realm gastropod genus in the Lower Devonian of the western hemisphere

Journal of Paleontology ◽

10.1017/s0022336000018266 ◽

2001 ◽

Vol 75 (2) ◽

pp. 466-470 ◽

Cited By ~ 5

Author(s):

Robert B. Blodgett ◽

Jiří Frýda ◽

Alfred C. Lenz

Keyword(s):

British Columbia ◽

Northwest Territories ◽

Lower Devonian ◽

Yukon Territory ◽

Western Hemisphere ◽

East Central ◽

Early Devonian ◽

Western Cordillera ◽

First Occurrence ◽

Mackenzie Mountains

Despite the rapidly expanding knowledge of Lower Devonian brachiopod faunas of the Western Cordillera of Canada (Lenz, 1976, 1977a, 1977b, 1982; Ludvigsen, 1970; Perry, 1984; Perry and Lenz, 1978; Perry et al., 1974, 1981), equivalent data on coeval gastropod faunas from this region are non-existent; to date, no publications have appeared in which gastropods have been described. Blodgett et al. (1988, table 1) provided faunal lists for two Lower Devonian localities in Western Canada: 1) Lochkovian-Emsian age collections from the Mackenzie Mountains, Northwest Territories, collected by the late D. G. Perry as part of his Ph.D. dissertation (Perry, 1984); and 2) an early Emsian collection from the Mt. Lloyd George area, British Columbia. We are currently examining the gastropod material recovered by A. C. Lenz from his richly diverse collections in the Royal Creek area, Yukon Territory, equivalent in age to those gathered by D. G. Perry from the Mackenzie Mountains. This note is the first of several papers focused on these paleobiogeographically significant faunas, and it is our desire to ultimately make clear the character of this Early Devonian province, which appears to include strata of British Columbia, Yukon and Northwest Territories, as well as the non-accreted portion of adjacent east-central Alaska.

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Jardamarekia enigma, a new Early Devonian tryblidioidean from Royal Creek area (Yukon Territory, Canada), and paleobiogeography of the Early Devonian of northwestern Canada

Zootaxa ◽

10.11646/zootaxa.2905.1.4 ◽

2011 ◽

Vol 2905 (1) ◽

pp. 57 ◽

Cited By ~ 1

Author(s):

JIŘÍ FRÝDA ◽

ROBERT B. BLODGETT ◽

ALFRED C. LENZ ◽

BARBORA FRÝDOVÁ

Keyword(s):

Lower Devonian ◽

Typical Feature ◽

Yukon Territory ◽

Western Canada ◽

Short Discussion ◽

Early Devonian ◽

Continental Shelves ◽

Molluscan Fauna ◽

Molluscan Species ◽

North Western

The Tryblidia (= Monoplacophora) represents the conchiferan class with the fewest Recent taxa in the phylum Mollusca (Haszprunar 2008) and its phylogeny is still poorly known. This group is known already in Cambrian strata (Early Paleozoic) more than 500 Ma ago. Present-day tryblidian species are known mainly from hadal environments (Schwabe 2008, but see also Wilson et al. 2009) in contrast to Paleozoic species, which have been described only from shallow environments of continental shelves of many paleocontinents (e.g., Horný 1962). A typical feature of fossil as well as living tryblidian species is their rarity. The vast majority of species are known only from several specimens (Haszprunar 2008). Furthermore, description of Paleozoic tryblidian molluscs is strongly underrepresented in the literature, despite the existence of diverse material. This is also true for fossils described in the present study based on a diverse silicified molluscan fauna of mostly gastropods collected from Lower Devonian strata of the Royal Creek area, Yukon Territory (Fig. 1) by Alfred C. Lenz and David G. Perry from 1970–1980. Lists of all hitherto described molluscan species as well as detailed information on their age and locality can be found in Lenz (1977a), Blodgett et al. (2001, 2010) and Frýda et al. (2008). Prior to our studies of the Royal Creek tryblidian and gastropod fauna, no descriptions or illustrations were available for Lower Devonian molluscs of north-western Canada, although a short discussion and faunal lists were provided by Blodgett et al. (1988) for Lower Devonian tryblidians and gastropods from the relatively nearby Delorme Formation of Northwest Territories, and early Emsian (late Early Devonian) tryblidians and gastropods from the Mt. Lloyd George area, northeastern British Columbia. The poor knowledge of Paleozoic tryblidians and gastropods faunas of Laurentia (North America) caused difficulties in the evaluation of Early Devonian paleobiogeography (Blodgett et al. 1999). The present paper is focused on the taxonomy of a new Devonian tryblidian limpet, but it provides also useful data for paleobiogeography and biostratigraphy of the Lower Devonian of western Canada.

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New porcellioidean gastropods from early Devonian of Royal Creek area, Yukon Territory, Canada, with notes on their early phylogeny

Journal of Paleontology ◽

10.1666/07-024.1 ◽

2008 ◽

Vol 82 (3) ◽

pp. 595-603 ◽

Cited By ~ 4

Author(s):

Jiří Frýda ◽

Robert B. Blodgett ◽

Alfred C. Lenz ◽

Štěpán Manda

Keyword(s):

Lower Devonian ◽

Yukon Territory ◽

Shell Morphology ◽

Western Canada ◽

Evolutionary Trend ◽

Early Devonian ◽

Old World ◽

The Road ◽

Classical Models

This paper presents a description of new gastropods belonging to the superfamily Porcellioidea (Vetigastropoda) from the richly diverse Lower Devonian gastropod fauna of the Road River Formation in the Royal Creek area, Yukon Territory. This fauna belongs to Western Canada Province of the Old World Realm. The Pragian speciesPorcellia(Porcellia)yukonensisn. sp. andPorcellia(Paraporcellia) sp. represent the oldest presently known members of subgeneraPorcellia(Porcellia) andPorcellia(Paraporcellia). Their simple shell ornamentation fits well with an earlier described evolutionary trend in shell morphology of the Porcellinae. Late Pragian to early EmsianPerryconcha pulchran. gen. and n. sp. is the first member of the Porcellioidea bearing a row of tremata on adult teleoconch whorls. The occurrence of this shell feature in the Porcellioidea is additional evidence that the evolution of the apertural slit was much more complicated than has been proposed in classical models of Paleozoic gastropod evolution.

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Late Early Devonian Dacryoconarid Tentaculites, Northern Yukon Territory

Canadian Journal of Earth Sciences ◽

10.1139/e72-024 ◽

1972 ◽

Vol 9 (3) ◽

pp. 297-318 ◽

Cited By ~ 8

Author(s):

Rolf Ludvigsen

Keyword(s):

New Species ◽

Environmental Factors ◽

Yukon Territory ◽

Early Devonian ◽

The Road ◽

Blackstone River

The late Early Devonian succession in northern Yukon Territory contains a well-preserved dacryoconarid tentaculite fauna dominated by Turkestanella acuaria (Richter) in the upper part of the Road River Formation and T. acuaria and Nowakia parabarrandei Churkin and Carter in the overlying Michelle Formation. Based on the dacryoconarid tentaculite fauna the bulk of the Michelle Formation in the Ogilvie to Hart Rivers area is dated as late Pragian (early Emsian), and based on the graptolite and dacryoconarid tentaculite fauna the uppermost Road River Formation in the Blackstone River area is dated as Pragian (early Emsian or late Siegenian or both). The appearance of species of Nowakia in northern Yukon considerably earlier than in Bohemia is documented. It is concluded that some genera of the Dacryoconarida were influenced in their occurrence by environmental factors. New species described are Turkestanella minuta, Viriatellina michellensis, Guerichina lenini, Styliolina blackstonensis, and Metastyliolina conica.

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Conodonts and associated graptolites from the late Early Devonian of east-central Alaska and western Yukon Territory

Canadian Journal of Earth Sciences ◽

10.1139/e85-200 ◽

1985 ◽

Vol 22 (12) ◽

pp. 1880-1883 ◽

Cited By ~ 8

Author(s):

Norman M. Savage ◽

Robert B. Blodgett ◽

Hermann Jaeger

Keyword(s):

North America ◽

Yukon Territory ◽

East Central ◽

Early Devonian ◽

Northern Siberia ◽

The North

Samples from two closely placed localities in western Yukon Territory have yielded late Early Devonian conodonts characteristic of areas farther to the north and east in Alaska and Yukon Territory and also characteristic of central and northern Siberia. Conodonts from a nearby locality in east-central Alaska indicate an age that makes the associated graptolites of considerable interest: they are among the youngest graptolites known in North America.

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New early Devonian gastropods from the families Crassimarginatidae (new family) and Scoliostomatidae (new family), Royal Creek Area, Yukon Territory, Canada

Journal of Paleontology ◽

10.1017/s0022336000041676 ◽

2002 ◽

Vol 76 (2) ◽

pp. 246-255 ◽

Cited By ~ 4

Author(s):

Jiří Frýda ◽

Robert B. Blodgett ◽

Alfred C. Lenz

Keyword(s):

New Species ◽

New Genus ◽

Yukon Territory ◽

New Genera ◽

Morphological Comparison ◽

The Czech Republic ◽

Early Devonian ◽

The Road ◽

New Family ◽

The Family

Two new distinctive families, Crassimarginatidae and Scoliostomatidae, each characterized by unusual gerontic apertural morphotypes, are established on the basis of study of the richly diverse Lower Devonian gastropod fauna of the Road River Formation in the Royal Creek area, Yukon Territory. The Early Devonian genus Crassimarginata Jhaveri, 1969, is transferred from the family Palaeotrochidae and placed, together with the new genus Yukonoconcha, into the new family Crassimarginatidae, which is characterized by a pupiform shell with an explanate outer apertural lip in the gerontic growth stage. The new family Scoliostomatidae unites Devonian gastropod genera (Scoliostoma Braun, 1838; Brilonella Kayser, 1873; Anarconcha Horný, 1964; Eoscoliostoma new genus; Mitchellia Koninck, 1877; and Pseudomitchellia new genus), which are characterized by a distinctive, free, twisted (both outwards and backwards) gerontic final half whorl. More detailed morphological comparison of members of this family has allowed their division into two new subfamilies: the Scoliostomatinae and Mitchelliinae. New genera include Yukonoconcha, Eoscoliostoma, and Pseudomitchellia. The former two genera are represented each by a single new species from Yukon Territory, Yukonoconcha pedderi and Eoscoliostoma norrisi. The latter genus is represented by two species, the type Pseudomitchellia bohemica (Perner) from the Koněprusy Limestone (Pragian) of the Czech Republic and Pseudomitchellia macqueeni new species from Yukon Territory.

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