Atrypoidea species from the Canadian Arctic islands

1981 ◽  
Vol 18 (10) ◽  
pp. 1539-1561 ◽  
Author(s):  
Brian Jones
Keyword(s):  
New Species ◽  
Morphological Analysis ◽  
Canadian Arctic ◽  
Ellesmere Island ◽  
Evolutionary Trends ◽  
Arctic Canada ◽  
Separate Species ◽  
Devon Island ◽  
Upper Silurian ◽  
The Relationship

Species of Atrypoidea have the potential of being biostratigraphically useful for the Upper Silurian strata of Arctic Canada. Critical to any biostratigraphic scheme is the relationship between A. phoca (Salter, 1852) and A. scheii (Holtedahl, 1914) since there is disagreement as to whether these species are synonymous, or distinct and stratigraphically separate species. Detailed morphological analysis of topotype A. scheii from Goose Fiord, Ellesmere Island shows that it falls within the range of morphological variation displayed by topotype A. phoca from Cape Riley, Devon Island. Consequently, A. scheii is maintained as a synonym of A. phoca.Other new species that may prove to be biostratigraphically useful include Atrypoidea gigantus n.sp. from an unnamed formation at Goose Fiord and A. netserki n.sp. from member C of the Read Bay Formation on Beechey Island. Atrypoidea gigantus, the largest species of Atrypoidea so far reported from Arctic Canada, is closely related to Atrypoidea foxi (Jones, 1974). Atrypoidea netserki is morphologically closest to A. phoca.Although the Atrypoidea sequences in the Ludlovian and Pridolian strata of Arctic Canada are now better known it is still difficult to delineate exact evolutionary trends, possibly because the various species have a facies- as well as a time-controlled distribution.

Middle Devonian brachiopods from the Bird Fiord Formation, Arctic Canada

2003 ◽  
Vol 77 (2) ◽  
pp. 243-266 ◽  
Author(s):  
Li Rong-Yu ◽  
Brian Jones
Keyword(s):  
New Species ◽  
Middle Devonian ◽  
Canadian Arctic ◽  
Ellesmere Island ◽  
The Arctic ◽  
Arctic Canada ◽  
Early Devonian ◽  
Delta Plain ◽  
The Cross

The late Early Devonian to Middle Devonian Bird Fiord Formation, which is up to 900 m thick, is exposed along an extensive outcrop belt from stretches from Ellesmere Island to Bathurst Island in Arctic Canada. This formation, which encompasses sediments that accumulated in sabkha, deltaic, and shelf settings, is divided into six members. The Blubber Point, Baad Fiord, Norwegian Bay, and Cardigan Strait members, which include sediments that formed on an open marine shelf, are characterized by a diverse biota of brachiopods, mollusks, corals, trilobites, and sponges. The Cross Bay and Grise Fiord members, which encompass sediments that formed in a sabkha and delta plain settings, respectively, are generally devoid of fossils.A collection of 47,026 brachiopods, which came from 140 collections made at 34 locations throughout the outcrop belt of the Bird Fiord Formation, contains 22 species of brachiopods that belong to 21 genera. This biota includes six new species: Gypidula mega, Spinatrypa (Isospinatrypa) parva, Desquamatia (Independatrypa) fortis, Nucleospira stelcki, Warrenella grinnellensis, and Cranaena briceae. Four genera (Arcticastrophia Li and Jones, 2002, Borealistrophia Li and Jones, 2002, Grinnellathyris Li and Jones, 2002, and Costacranaena Johnson and Perry, 1976) and 16 species of brachiopods are endemic to the Arctic Canada. Conversely, the fauna also includes European elements such as Nucleospira lens (Schnur), Spinatrypa (Isospinatrypa), and Warrenella. These taxa may indicate that there was some communication between the Canadian Arctic and Europe during Middle Devonian.

Heliolitine corals of the topmost Douro and overlying formations (Upper Silurian), Canadian Arctic islands

1998 ◽  
Vol 72 (6) ◽  
pp. 937-966 ◽  
Author(s):  
Owen A. Dixon
Keyword(s):  
New Species ◽  
Canadian Arctic ◽  
Unidentified Species ◽  
Upper Silurian ◽  
Somerset Island

Heliolitine corals occur in Upper Silurian strata of the topmost Douro, lower Barlow Inlet, and lower Somerset Island formations in the Boothia Uplift region. The fauna includesHeliolites(nine species),Propora(two species), the stelliporellid generaPodollites(three species) andStelliporella(one species), and the plasmoporidSquameolites(one species). Species present but not previously reported from the region includeHeliolites arcuatusBondarenko,Heliolites uksunayensisMironova,Stelliporella ilensisBondarenko,Podollites assitusnew species,Podollites parryinew species,Podollites plectilisnew species,Propora tubulata(Lonsdale) and an unidentified species ofPropora.All species occur in reef and reef-associated facies of open carbonate shelf and ramp settings. In restricted nonreefal carbonate shelf settings, diversity attenuates to a minimum, exemplified by numerically abundant monospecific assemblages ofHeliolites uksunayensis.Six of the 16 morphotaxonomic units recognized compare with species reported previously in Silurian faunas of Kazakhstan and Mongolia. Combinations of characters in the species attributed toPodollitessupport revision of the genus, possibly to includeDerivatolitesandTarbagatailites, in a group morphologically intermediate betweenStelliporellaandHeliolites.

Systematics of the Acanthoparyphinae (Trilobita), by species from the Silurian of Arctic Canada

1998 ◽  
Vol 72 (4) ◽  
pp. 698-718 ◽  
Author(s):  
Jonathan M. Adrain
Keyword(s):  
New Species ◽  
Type Species ◽  
Cladistic Analysis ◽  
Canadian Arctic ◽  
Entire Group ◽  
Arctic Canada ◽  
Basal Node ◽  
The Family ◽  
Cape Phillips Formation ◽  
Basal Structure

Cladistic analysis of the trilobite subfamily Acanthoparyphinae Whittington and Evitt, 1954, yields an explicit hypothesis of relationship for the group. All Silurian species together form a robustly supported monophylum including the genera Hyrokybe Lane, 1972, Parayoungia Chatterton and Perry, 1984, and Youngia Lindström, 1885. Sister to this is the Ordovician type species of Acanthoparypha Whittington and Evitt, 1954. Remaining species that have historically been assigned to either Acanthoparypha or Pandaspinapyga Esker and Levin, 1964, form a rather labile paraphylum. Nevertheless, the entire group thus identified is definitely monophyletic, and supported by several prominent synapomorphic character-states.The basal structure and basal node of the subfamily are more difficult to assess. The relationships of the genera Hammannopyge Přibyl, Vaněk, and Pek, 1985, Holia Bradley, 1930, and Nieszkowskia Schmidt, 1881, need to be addressed within the wider context of the family as a whole. The traditional assignment of Holia to the acanthoparyphines is followed.Wenlock acanthoparyphines from the Cape Phillips Formation of the central Canadian Arctic islands include several species of Hyrokybe and Parayoungia. They are similar to, and in one case conspecific with, coeval forms to the southwest in the southern Mackenzie Mountains.Five species are new: Holia glabra, Hyrokybe lightfooti, Hyrokybe youngi, Hyrokybe mitchellae, and Parayoungia mclaughlini. At least four other potentially new species are reported in open nomenclature.

scholarly journals Upper Ordovician – Upper Silurian conodont biostratigraphy, Devon Island and southern Ellesmere Island, Canadian Arctic Islands, with implications for regional stratigraphy, eustasy, and thermal maturation

2016 ◽  
Vol 53 (9) ◽  
pp. 931-949 ◽  
Author(s):  
Shunxin Zhang ◽  
Khusro Mirza ◽  
Christopher R. Barnes
Keyword(s):  
Canadian Arctic ◽  
Hydrocarbon Exploration ◽  
Upper Ordovician ◽  
Conodont Biostratigraphy ◽  
Thermal Maturation ◽  
Devon Island ◽  
The North ◽  
Cape Phillips Formation ◽  
Upper Silurian ◽  
Local Range

The conodont biostratigraphy for the Upper Ordovician – Upper Silurian carbonate shelf (Irene Bay and Allen Bay formations) and interfingering basinal (Cape Phillips Formation) facies is established for parts of Devon and Ellesmere islands, central Canadian Arctic Islands. Revisions to the interpreted regional stratigraphic relationships and correlations are based on the stratigraphic distribution of the 51 conodont species representing 32 genera, identified from over 5000 well-preserved conodonts recovered from 101 productive samples in nine stratigraphic sections. The six zones recognized are, in ascending order, Amorphognathus ordovicicus Local-Range Zone, Aspelundia fluegeli Interval Zone, Pterospathodus celloni Local-Range Zone, Pt. pennatus procerus Local-Range Zone, Kockelella patula Local-Range Zone, and K. variabilis variabilis – Ozarkodina confluens Concurrent-Range Zone. These provided a more precise dating of the members and formations and, in particular, the range of hiatuses within this stratigraphic succession. The pattern of regional stratigraphy, facies changes, and hiatuses is interpreted as primarily related to the effects of glacioeustasy associated with the terminal Ordovician glaciation and smaller Early Silurian glacial phases, the backstepping of the Silurian shelf margin, and the geodynamic effects of the collision with Laurentia by Baltica to the east and Pearya to the north. Conodont colour alteration index values (CAI 1–6.5) from the nine sections complement earlier graptolite reflectance data in providing regional thermal maturation data of value in hydrocarbon exploration assessments.

Reassessment of Ischnacanthus? scheii Spjeldnaes (Acanthodii, Ischnacanthiformes) from the latest Silurian or earliest Devonian of Ellesmere Island, arctic Canada

2013 ◽  
Vol 50 (9) ◽  
pp. 945-954 ◽  
Author(s):  
Carole J. Burrow
Keyword(s):  
Canadian Arctic ◽  
Biological Species ◽  
Ellesmere Island ◽  
Canadian Arctic Archipelago ◽  
Devon Island ◽  
Thin Sectioning ◽  
Bone Fragments ◽  
Cornwallis Island ◽  
North Greenland ◽  
Fin Spines

Articulated specimens of jawed fishes, and assemblages of disarticulated elements that can be assigned to a single biological species, are extremely rare from pre-Devonian deposits. The acanthodian species Ischnacanthus? scheii Spjeldnaes is based on a monospecific assemblage, comprising fin spines, dentigerous jaw bone fragments and scales, from the ?Siluro-Devonian boundary beds of the Devon Island Formation in central west Ellesmere Island, Canadian Arctic Archipelago, Nunavut. A new examination of the type material, in particular by scanning electron microscopy and thin sectioning of scales, shows that the species is a porosiform poracanthodid that is now assigned to Radioporacanthodes scheii comb. nov. Scales of the same species are also recognized from the upper Pridoli of Cornwallis Island and the ?Pridoli or Lochkovian of north Greenland.

Apparent Radiocarbon Ages of recent marine shells from Norway, Spitsbergen, and Arctic Canada

1975 ◽  
Vol 5 (2) ◽  
pp. 263-273 ◽  
Author(s):  
Jan Mangerud ◽  
Steinar Gulliksen
Keyword(s):  
Fossil Fuels ◽  
Atomic Bomb ◽  
Circulation Pattern ◽  
Ellesmere Island ◽  
Oceanic Circulation ◽  
Arctic Canada ◽  
The Mean ◽  
Main Input ◽  
The Relationship

The mean apparent radiocarbon ages of marine shells, colleted alive before the initiation of atomic bomb testing, and also before the main input of dead carbon derived from fossil fuels, are found to be 440 yr for the coast of Norway, 510 yr for Spitsbergen, and 750 yr for Ellesmere Island, Arctic Canada. The relationship between these apparent ages and the oceanic circulation pattern, is discussed. Also possible variations of the apparent ages back in time are discussed.

ESTIGENA WALLACEI SP. NOV. FROM WEST FLORES, INDONESIA (LEPIDOPTERA: LASIOCAMPIDAE)

2019 ◽  
Vol 22 ◽  
pp. 27-33
Author(s):  
Vitaly M. Spitsyn ◽  
Ivan N. Bolotov ◽  
Alexander V. Kondakov ◽  
Alena A. Tomilova
Keyword(s):  
New Species ◽  
Endemic Species ◽  
Species Level ◽  
Single Female ◽  
Separate Species ◽  
The Relationship

Here we describe Estigena wallacei sp. nov., an endemic species from West Flores, Indonesia. No Estigena species were known from Flores Island so far, while E. caesarea (Zolotuhin & Witt, 2005) was described from Timor Island. The relationship between these two taxa is unclear, because E. caesarea was described based on four male specimens, whereas our species from Flores is known from a single female. However, the COI sequence of E. cf. caesarea from Timor available in the BOLD database is distant from that of the new species supporting our taxonomic hypothesis on the separate species-level status of E. wallacei sp. nov.

Upper Silurian trilete spores and other microfossils from the Read Bay Formation, Cornwallis Island, Canadian Arctic

1978 ◽  
Vol 15 (8) ◽  
pp. 1292-1303 ◽  
Author(s):  
D. C. McGregor ◽  
G. M. Narbonne
Keyword(s):  
New Species ◽  
Marine Environment ◽  
Vascular Plants ◽  
Canadian Arctic ◽  
Type Section ◽  
Stratigraphic Framework ◽  
Near Shore ◽  
Upper Silurian ◽  
One New Species ◽  
Cornwallis Island

A diverse palynomorph assemblage of trilete spores, tetrads, acritarchs, chitinozoans, scolecodonts, and fragments of arthropods, ?hydrozoans, ?graptolites, and possibly nematophytalean and vascular plants occurs 20 m above the base of member B of the Read Bay Formation at the type section on eastern Cornwallis Island, District of Franklin. This assemblage, here described briefly, is late Ludlow according to faunas above and below. The palynomorphs, other fossils, and stratigraphic framework indicate that the shales of member B were deposited in a sheltered near-shore marine environment. One new species of trilete spores, Retusotriletes chartulatus McGregor, is erected.

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