Upper Triassic sponges (Sphinctozoa) from southern Yukon, Stikinia terrane

1987 ◽  
Vol 24 (5) ◽  
pp. 882-902 ◽  
Author(s):  
Baba Senowbari-Daryan ◽  
R. Pamela Reid

The first Tethyan-type Upper Triassic sponge reefs in North America have recently been discovered in the southern Yukon, in Stikinia terrane. Sphinctozoa from these reefs and inter-reef limestones are represented by 18 species and 12 genera belonging to six families. The genus Yukonella with one species, Y. rigbyi, and the species Polytholosia ramosa and Polycystocoelia norica are described for the first time. Some of the Yukon sponges were previously known only from the Tethyan realm (Colospongia, Dictyocoelia, Polycystocoelia, and Uvanella?); others, from Tethyan and North American localities (Ascosymplegma, Follicatena, Paradenigeria, and Salzburgia?). One (Polytholosia cylindrica) is probably endemic to North America. The mixed affinities of the Yukon sponges may reflect the paleogeographic origin of Stikinia as an island in the ancestral Pacific Ocean, between Tethys and the North American craton.

1994 ◽  
Vol 68 (S36) ◽  
pp. 1-33 ◽  
Author(s):  
George D. Stanley ◽  
Carlos González-León ◽  
Michael R. Sandy ◽  
Baba Senowbari-Daryan ◽  
Peter Doyle ◽  
...  

A diverse Upper Triassic tropical marine fauna from northwestern Sonora, Mexico, includes 31 taxa of tropical invertebrates including scleractinian corals, spongiomorphs, disjectoporoids, “hydrozoans,” thalamid and nonthalamid sponges, spiriferid and terebratulid brachiopods, gastropods, bivalves, coleoids, and anomuran microcoprolites. They occur within the late Karnian to Norian part of the Antimonio Formation (Antimonio terrane), which is juxtaposed against a fragmented portion of the North American craton. Most of the fauna is also known from the Tethys region. Sixteen Sonoran taxa co-occur in the western Tethys and five have never been known outside this region. Four additional taxa (one identified only at genus level) are geographically widespread. Some taxa occur in displaced terranes of North America, especially in west-central Nevada (Luning Formation). A weak link exists with the California Eastern Klamath terrane but stronger ties exist with Peru. Among Sonoran sponges,Nevadathalamia polystomawas previously recognized only from the Luning Formation, western Nevada. SpongesCinnabaria expansa, Nevadathalamia cylindrica, and a coral,Astraeomorpha sonorensisn. sp., are also known from Nevada. The coralsDistichomeandra austriaca, Chondrocoenia waltheri, Pamiroseris rectilamellosa, andAlpinophyllia flexuosaco-occur in central Europe. Two new taxa, a spongiomorph hydrozoan,Stromatoporidium lamellatumn. sp., and a disjectoporoid,Pamiropora sonorensisn. sp., have distinct affinities with the Tethys. The geographically widespread North American brachiopod,Spondylospira lewesensis, andPseudorhaetina antimoniensisn. gen. and sp. are among the Sonoran fauna. The Sonoran coleoid (aulacocerid)Dictyoconites(Dictyoconites) cf.D. reticulatumoccurs in the Tethys realm andCalliconitescf.C. drakeiis comparable with a species from the Eastern Klamath terrane.Calliconites millerin. sp. is the first occurrence of the genus outside Sicily. The bivalvesMyophorigonia jaworskii, M. salasi, andPalaeocardita peruvianaare known from Sonora and Peru. Eight gastropod taxa includeGuidoniacf.G. intermediaandG.cf.G. parvula, both previously known from Peru, andEucycloscala subbisertusfrom the western Tethys. The gastropods are unlike those already known from other North American terranes.


2011 ◽  
Vol 85 (1) ◽  
pp. 29-31
Author(s):  
George D. Stanley ◽  
John-Paul Zonneveld

Cassianastraea is an enigmatic colonial Triassic cnidarian first described as a coral but subsequently referred to the Hydrozoa. We report here the first occurrence in Canada of fossils we designate as Cassianastraea sp. from the Williston Lake region of British Columbia. The specimens come from older collections of the Geological Survey of Canada, collected in Upper Triassic (Carnian) strata assigned to either the Ludington or Baldonnel Formations. While well known in reef associations of the former Tethys region, Cassianiastraea is relatively rare in North America. The Carnian Baldonnel Formation contains the earliest coral reefs from the North American craton and we suspect that Cassianastraea sp. also came from this reef association.


1990 ◽  
Vol 68 (11) ◽  
pp. 2338-2351 ◽  
Author(s):  
S. A. Marshall ◽  
Ian P. Smith

All macropterous species of Aptilotus Mik are keyed, with descriptions of two new macropterous North American species, Aptilotus pogophallus and A. nigriphallus. New distributional records are given for other North American species, and brachyptery is noted for the first time in A. luctuosus (Spuler). Four new macropterous species of Aptilotus (glabrifrons, spinistylus, rufiscapus, and binotatus are described from Nepal. The relationships between the North American and Nepalese species are discussed. Minocellina Papp is synonomized with Aptilotus, and the two species formerly in Minocellina, A. thaii (Papp) and A. besucheti (Papp), are thus given as new combinations. Limosina carbonicolor Richards, from Ethiopia, is redescribed and transferred to Aptilotus.


2005 ◽  
Vol 83 (9) ◽  
pp. 1075-1081 ◽  
Author(s):  
Irwin M. Brodo ◽  
André Aptroot

Protoparmelia hypotremella van Herk, Spier & V. Wirth is reported here as an addition to the North American lichen flora. Fertile material of P. hypotremella was found for the first time, and it is described in detail. The hyaline hair-like appendages on both polar ends of the ascospores, characteristic of the genus, are illustrated for the first time. The species is then compared with Protoparmelia ochrococca , known from western North America, and Protoparmelia oleagina , still known only from Europe. A key to the corticolous species of Protoparmelia is provided.


1999 ◽  
Vol 36 (3) ◽  
pp. 479-494 ◽  
Author(s):  
Martin de Keijzer ◽  
Paul F Williams ◽  
Richard L Brown

The Teslin zone in south-central Yukon has previously been described as a discrete zone with a steep foliation unique to the zone. It includes the Anvil assemblage and the narrowest portion of the Yukon-Tanana terrane (the Nisutlin assemblage), and is defined by post-accretionary faults: the Big Salmon fault to the west and the d'Abbadie fault system to the east. The zone was interpreted as a lithospheric suture or a crustal-scale transpression zone, and as the root zone of klippen lying on the North American craton to the east. We demonstrate that deformation and metamorphism are the same inside and outside the zone. The steep transposition foliation in the zone, in contrast to adjacent rocks to the east, coincides with the steep limb of a regional F3 structure. This fold has a shallow limb in the easternmost part of the zone and immediately east of the zone. Thus we reject earlier interpretations. If a suture exists between the obducted Anvil and Yukon-Tanana Nisutlin assemblages and North America, it is a shear zone that occurs at the base of the obducted rocks, which has been folded by the F3 fold. However, evidence that this thrust boundary is a lithospheric suture is lacking. A consequence of our interpretation is that North American rocks pass under the eastern Teslin zone and outcrop to the west of the Nisutlin and Anvil assemblages. This geometry precludes the possibility of the Teslin zone being the root zone of the klippen.


1992 ◽  
Vol 6 ◽  
pp. 97-97
Author(s):  
Stanley C. Finney ◽  
Raymond L. Ethington

Two very different plate-tectonic models have been proposed to explain the development and emplacement of the Robert Mountains allochthon (RMA) onto the North America craton during the Late Devonian-Early Mississippian Antler Orogeny. In one model, the RMA represents a far-traveled accretionary prism that migrated eastwards over a west-dipping subduction zone. In the other, the eugeoclinal strata of the RMA were deposited on the continental rise of western North America within a closed back-arc basin. Siliciclastic sediments, especially quartz sandstones, compose much of the RMA, yet knowledge of their provenance is poor even though such knowledge is essential for evaluating the two plate-tectonic models.We have recently obtained large collections of graptolites and conodonts from turbiditic quartz sandstones in the Lower Member of the Vinini Formation in the Roberts Mountains. These sandstones of lower Whiterockian age are correlative with the lower Antelope Valley Limestone that deposited on the western shelf of North America. The diverse graptolite fauna represents the oceanic isograptid fauna. However, it also includes pendent didymograptids and rooted dendroids that were restricted to shallow shelf seas. The dendroids (Cactograptus, Dendrograptus, Desmograptus, and Dictyonema) were benthic organisms, could not have lived in a deep marine setting, and are also common in shallow-water carbonate strata of western Utah. All specimens within the turbiditic quartz sandstones of the Vinini were broken before final deposition and burial, but specimens from Utah are generally complete. The diverse conodont fauna is virtually identical to that found in the lower Antelope Valley Limestone, as well as in coeval strata in western Utah. Although it includes a few deep (cold) water, cosmopolitan species, it is dominated by species that are otherwise known only from shallow water strata deposited on the North American craton.We conclude that turbidity currents transported these exotic graptolites and conodonts down from the shelf and onto the rise along with the quartz sands in which they occur. Thus, the Whiterockian quartz sandstones in the Vinini Formation must have a North American provenance just as the fossils do. This is strong evidence that 1) the RMA is not exotic to North America, 2) the eugeoclinal strata of the RMA were deposited on the western continental rise of North America and on the eastern side of a back-arc basin, and 3) the RMA was thrust onto the western shelf of North America by closure of this back-arc basin.


2009 ◽  
Vol 42 (1) ◽  
pp. 55-71 ◽  
Author(s):  
Erin A. TRIPP ◽  
James C. LENDEMER ◽  
Richard C. HARRIS

AbstractAs part of our ongoing studies of the Graphidaceae in North America, we resolve the status of all taxa traditionally assigned to the genus Graphina that have been reported from the continent north of Mexico. Treatments for the North American members of Acanthothecis, Carbacanthographis, and Diorygma are presented because several species of Graphina have been reassigned to these genera, and our studies of accumulated herbarium materials revealed the existence of several previously unreported and unrecognized species. The following new combinations are made: Acanthothecis leucopepla, A. mosquitensis, A. peplophora, and A. poitaeoides. Carbacanthographis muriformis is described as new to science based on material from Florida. The following taxa are reported from North America for the first time: Acanthothecis poitaeoides,Diorygma junghuhnii, D. reniforme.


2007 ◽  
Vol 85 (3) ◽  
pp. 342-346 ◽  
Author(s):  
J. Kout ◽  
J. Vlasák

The polypore Trametes gibbosa (Pers.) Fries, common in Europe and Asia, is reported from eastern North America for the first time. Single basidiospore cultures from Pennsylvania, United States, and Quebec, Canada, were paired with each other and with cultures from the Czech Republic. The North American intercollection crosses were 60% compatible and 100% compatible with the Czech cultures. All the crosses among the Czech cultures were 100% compatible. The recent introduction of T. gibbosa to North America is suggested as a possible explanation for the limited number of mating-type alleles and subsequent incompatibility among the North American cultures.


1974 ◽  
Vol 52 (11) ◽  
pp. 2427-2434 ◽  
Author(s):  
C. D. Bird

The four North American species of Evernia, E. divaricata (L.) Ach., E. mesomorpha Nyl., E. perfragilis Llano, and E. prunastri (L.) Ach., are discussed from the standpoint of taxonomy, distribution, and ecology. The North American distributions of E. divaricata and E. perfragilis are mapped for the first time. A puzzling lichen found on the ground in alpine areas from New Mexico north to Alberta is regarded as an ecological variant of E. divaricata.


2007 ◽  
Vol 243 (3-4) ◽  
pp. 421-450 ◽  
Author(s):  
John-Paul Zonneveld ◽  
Charles M. Henderson ◽  
George D. Stanley ◽  
Michael J. Orchard ◽  
Murray K. Gingras

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