The graptolite Amplexograptus praetypicalis n. sp. and the origin of the typicalis group

1987 ◽  
Vol 24 (5) ◽  
pp. 924-933 ◽  
Author(s):  
John Riva
Keyword(s):  
North America ◽  
Related Species ◽  
Type Species ◽  
Distinct Group ◽  
Late Ordovician ◽  
Lower Half ◽  
Northeastern North America ◽  
Distinct Process ◽  
Distinct Lineage ◽  
Early Late

The graptolite Amplexograptus praetypicalis n. sp. is described and assigned to a more precisely defined and amended genus Amplexograptus Elles and Wood. This graptolite ranges through the lower half of the Climacograptus spiniferus Zone of northeastern North America and evolves, through a distinct process of phyletic gradualism, into the better known Climacograptus typicalis Hall. Climacograptus typicalis ranges through the upper half of the C. spiniferus Zone and the succeeding Climacograptus pygmaeus Zone, giving rise to three related species: the dwarfish Climacograptus pygmaeus Ruedemann, the gigantic Climacograptus magnificus Twenhofel, and the atavistic Climacograptus posterus Ruedemann. Together, these four species form a distinct group, termed the typicalis group, and a distinct lineage that had a brief existence from the late Middle to the early Late Ordovician. The genus Uticagraptus n. g. is here proposed for the graptolites of the typicalis group. This group is characterized by an advanced prosoblastic type of proximal-end development and an aseptate rhabdosome and, thus, differs fundamentally from Climacograptus bicornis (Hall), the type species of Climacograptus, with a more primitive diplograptid type of proximal-end development and a septate rhabdosome.

Designation of a neotype and paraneotype for Conularina triangulata (Raymond, 1905) (Upper Ordovician, eastern North America)

2020 ◽  
Vol 94 (4) ◽  
pp. 796-797
Author(s):  
Heyo Van Iten ◽  
Mario E. Cournoyer ◽  
Michelle Coyne
Keyword(s):  
New York ◽  
North America ◽  
Late Ordovician ◽  
Quebec City ◽  
Eastern North America ◽  
Upper Ordovician ◽  
Thrust Sheet ◽  
City Formation ◽  
Early Late

Conularina triangulata (Raymond, 1905), the genotype of Conularina Sinclair, 1942, is a rare, early Late Ordovician conulariid (Cnidaria, Scyphozoa; Van Iten et al., 2006) having three sides or faces instead of four (Sinclair, 1942, fig. 9; Van Iten, 1992, text-fig. 3E). Originally described from the Valcour Formation (early Sandbian; Dix et al., 2013) on Valcour Island, New York (Sinclair, 1942), C. triangulata has since been found in laterally equivalent strata of the upper Laval Formation (‘Upper Chazy’; Sinclair, 1942) in Laval, Québec, Canada (Sinclair, 1942). From this same unit and area, Sinclair (1942) erected three new, four-sided species of Conularina (C. irrasa, C. raymondi, and C. undosa), and he erected a single four-sided species (C. narrawayi) from the Ottawa Formation (now the Sandbian–Katian Ottawa Group; Dix et al., 2013) at Tétreauville (now Gatineau), Québec. Subsequently, Jerre (1994) reported the occurrence of two species of Conularina in the Upper Ordovician of Sweden. Jerre (1994) also proposed that Eoconularia? forensis Sinclair, 1946 from the Upper Ordovician Citadelle Formation (‘Quebec City’ Formation; Sinclair, 1946) in Québec City, Québec (Promontoire de Québec thrust sheet, Appalachian Humber Zone, Allochtonous Domain; Castonguay et al., 2002) is a species of Conularina.

Age and correlation of the Honorat Group, southern Gaspé Peninsula

1988 ◽  
Vol 25 (10) ◽  
pp. 1618-1628 ◽  
Author(s):  
John Riva ◽  
Michel Malo
Keyword(s):  
United States ◽  
North America ◽  
New Brunswick ◽  
Wide Distribution ◽  
Late Ordovician ◽  
Eastern North America ◽  
North Central ◽  
Middle Ordovician ◽  
The Pacific ◽  
Early Late

The Honorat Group of southern Gaspé consists of two formations: the Arsenault and the Garin. The Arsenault Formation, heretofore considered barren, has yielded a graptolite faunule indicative of a Llanvirn–Llandeilo age (early Middle Ordovician), suggesting a correlation with the lower Mictaw Group of Gaspé as revised by de Broucker. A hiatus of indeterminate magnitude, corresponding to the Taconic unconformity, probably separates the Arsenault Formation from the overlying Garin Formation. The Garin has yielded graptolites ranging from the upper Climacograptus spiniferus Zone to the Paraclimatograptus manitoulinensis Zone (late Middle to early Late Ordovician). The C. spiniferus Zone graptolites are identical to those of the upper γ sequence of the Cloridorme Formation of northern Gaspé and the Blind Brook Formation of the Munsungun Anticlinorium of Maine but differ somewhat from those from the upper Tetagouche Group of New Brunswick, which are closer to those from the Summerford and Exploits groups of north-central Newfoundland. The C. spiniferus zone has a wide distribution in eastern North America. It correlates with the Orthograptus amplexicaulis Zone of the southwestern United States and with the Climacograptus baragwathi Zone (Ea2) of the Pacific faunal province.The Matapédia Group, stratigraphically above the Honorat Group, has yielded both shelly fossils and a few graptolites. The ages of the graptolites now date it as Late Ordovician to late Early Silurian (Dicellograptus complanatus Zone – Monograptus sedgwickii Zone).

Taxonomic status of diploid Salicornia europaea (s.l.) (Chenopodiaceae) in northeastern North America

1987 ◽  
Vol 65 (7) ◽  
pp. 1420-1426 ◽  
Author(s):  
S. L. Wolff ◽  
R. L. Jefferies
Keyword(s):  
North America ◽  
North American ◽  
Taxonomic Status ◽  
Distinct Group ◽  
Salicornia Europaea ◽  
Electrophoretic Variation ◽  
Northeastern North America ◽  
Anther Length ◽  
Length Width ◽  
Diploid Populations

The taxonomic status of diploid Salicornia europaea L. (s.l.) in northeastern North America has been evaluated based on morphological and electrophoretic variation within and between populations. Populations of two European diploid micro-species, S. ramosissima J. Woods and S. europaea (s.s.), and populations of the midwestern diploid, S. rubra A. Nels., were also examined, affording a comparison between North American S. europaea (s.l.) and recognized species. Anther length, width of the scarious border of the fertile segment, and floral perianth shape were used to subdivide North American diploid populations into two groups. These groups were morphologically distinct from S. rubra and the European microspecies. The electrophoretic profile was unique in each morphologically distinct group of populations of S. europaea (s.l.) in northeastern North America. Based on morphological, geographical, and electrophoretic differences, diploid populations of S. europaea (s.l.) from this region are assigned to one of the following two new species: S. maritima Wolff & Jefferies, sp.nov., and S. borealis Wolff & Jefferies, sp.nov. The tetraploids are retained in S. europaea (s.l.).

Revision, distribution, and extinction of the Middle and early Late Devonian archaeogastropod genera Floyda and Turbonopsis

1987 ◽  
Vol 61 (5) ◽  
pp. 960-973 ◽  
Author(s):  
Jed Day
Keyword(s):  
United States ◽  
North America ◽  
Type Species ◽  
The United States ◽  
Late Devonian ◽  
Western North America ◽  
Bottom Waters ◽  
Rhenish Slate Mountains ◽  
Oceanic Currents ◽  
Early Late

Large palaeotrochid gastropods of the genera Floyda Webster (1905a) and Turbonopsis Grabau and Shimer (1909) occur in the late Frasnian Lime Creek Formation of Iowa. Floyda concentrica was designated as the type species of Floyda by earlier workers (Webster, 1905a; Knight, 1941), but is a junior synonym of F. gigantea (Hall and Whitfield, 1873). Three of five species and subspecies of Floyda described from the Lime Creek (Floyda concentrica, F. concentrica multisinuata, and F. gigantea depressa) are considered synonyms of the type species F. gigantea; the fifth species, F. gigantea hackberryensis, is here reassigned to the closely related genus Turbonopsis. Both F. gigantea and T. hackberryensis are redescribed using the original types and additional hypotype material from the collections of Charles Belanski.Floyda, first known from late Givetian rocks of the Rhenish Slate Mountains in Germany, is widespread in the United States Midcontinent and western North America by early Late Devonian time. Turbonopsis was endemic to the Appohimchi Subregion of the Eastern Americas Realm prior to the Taghanic Onlap, and appears to have remained so until late Frasnian time when it migrated to western North America.Eustatic sea-level highstands during the Middle and Late Devonian are thought to have breached barriers to migration, allowing both Floyda and Turbonopsis to disperse by prevailing oceanic currents from the United States Midcontinent into western North America during the late Frasnian. The expected oceanic current patterns of the Middle and Late Devonian paleogeographic reconstructions of Heckel and Witzke (1979, figs. 3, 5) adequately account for the known distribution and dispersal of Devonian palaeotrochid gastropods.The Palaeotrochidae underwent extinction prior to the latest Frasnian. Floyda, Turbonopsis, and Westerna became extinct during the onset of the last eustatic deepening event prior to the close of the Frasnian. The extinction of the palaeotrochid gastropods as well as other invertebrate groups may have been the result of restriction or near elimination of shallow warm-water, well-oxygenated shelf habitats by the onlap of cold anoxic bottom waters prior to latest Frasnian time.

The polyplacophoran “Chiton” carbonarius Stevens, 1858, in North America and new related species

1986 ◽  
Vol 60 (3) ◽  
pp. 627-635 ◽  
Author(s):  
R. D. Hoare ◽  
R. H. Mapes
Keyword(s):  
North America ◽  
Relative Abundance ◽  
Related Species ◽  
Type Species ◽  
Appalachian Basin ◽  
Calcareous Algae ◽  
Root Stock

“Chiton” carbonarius Stevens, 1858, is reassigned as the type species to Glaphurochiton Raymond, 1910. This species evolved from an unknown Mississippian ancestor, and spread rapidly into the Midcontinent region, Eastern Interior, and Appalachian basins during the Morrowan. Glaphurochiton carbonarius served as the root stock for development of several species: G. concinnus (Richardson) during the Desmoinesian and G. subcircularis n. sp. during the Virgilian in the Eastern Interior basin and G. elimatus n. sp. in the Appalachian basin and possibly G.? riddlei (Frederickson) in the Midcontinent region during the Missourian.Glaphurochiton is believed to have been essentially restricted to a mud bottom based upon its occurrence and relative abundance. Commonly the only taxon present, often abundantly, in black and gray shales, Glaphurochiton is rare to absent in limestones, algal limestones, reefs, and shales with an abundance of crustose calcareous algae. The latter lithologies commonly support a diverse polyplacophoran fauna essentially lacking Glaphurochiton.

The Corynexochina (Trilobita): a poorly understood suborder

2009 ◽  
Vol 83 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Harry B. Whittington
Keyword(s):  
North America ◽  
Type Species ◽  
Distinct Group ◽  
Geographical Range ◽  
Type Material ◽  
Growth Stages ◽  
Similar Material ◽  
Northern Spain ◽  
Middle Cambrian ◽  
Southern France

Trilobites of this suborder from Europe and North America have not been studied in detail, in contrast to the attention given to relationships within the orders Agnostida and Ptychopariina. The basis of the Corynexochina is the type species of Corynexochus from the middle Cambrian of Sweden. The type material redescribed here is only the cranidium, and is inadequate for diagnosis of the genus. A species attributed to this genus occurring in the Cambrian of southern France is represented by entire dorsal exoskeletons and is urgently in need of redescription. Similar material is recorded in northern Spain. Both complete exoskeletons and growth stages of Corynexochina have been described from Cambrian strata in Russia, Australia, Morocco and China, showing the wide geographical range and varied morphology of the Suborder. The type species of two genera from boulders of middle Cambrian age found in Quebec, Canada, are redescribed from exceptionally well preserved, though small, specimens. They appear to represent a distinct group related to some of the Zacanthoididae. Families of Corynexochina are inadequately discriminated one from another, so that a family name can only be used with question. Until this is remedied, diagnosis of a new group is not possible.

Three New Ontario Black Flies of the Genus Prosimulium (Diptera: Simuliidae): Part II. Ecological Observations and Experiments

1958 ◽  
Vol 90 (12) ◽  
pp. 744-759 ◽  
Author(s):  
Douglas M. Davies ◽  
Paul D. Syme
Keyword(s):  
New Species ◽  
North America ◽  
Related Species ◽  
Larval Growth ◽  
Larval Feeding ◽  
Black Flies ◽  
Northeastern North America ◽  
The World ◽  
Three New Species

In an earlier paper (Syme and Davies, 1958), three new species in the hirtipes-complex (Prosimulium fuscum Syme and Davies, P. mixtum Syme and Davies and P. fontanum Syme and Davies) were described, compared with related species in other parts of the world, and their known distribution in northeastern North America indicated. In this paper are presented observations on the manner and dates of oviposition, on incubation, on the larval feeding, on the rate of larval growth during the fall and winter in a spring-fed stream, and on differences in habitat and seasonal emergence of the three new species.

Parastrophinella (Brachiopoda): Its paleogeographic significance at the Ordovician/Silurian boundary

1997 ◽  
Vol 71 (3) ◽  
pp. 369-380 ◽  
Author(s):  
Jisuo Jin ◽  
Paul Copper
Keyword(s):  
North America ◽  
Type Species ◽  
Late Ordovician ◽  
Eastern North America ◽  
Hudson Bay ◽  
Morphologic Change ◽  
Baffin Island ◽  
Median Septum ◽  
Lamellar Layer ◽  
Anticosti Island

The type species of Parastrophinella, P. reversa, a pentamerid brachiopod from the uppermost Ordovician (Hirnantian) Ellis Bay Formation of Anticosti Island, Quebec, shows that the genus is characterized by three features: 1) a ventral median septum apically buried in a thickened valve floor, but anteriorly rising above valve floor; 2) prominent alate plates, which are homologous to brachial processes; and, 3) a pseudocruralium consisting of a dorsal median septum, which is largely buried in the valve floor posteriorly, and outer plates that are connected to the median septum via prismatic substance (with poorly developed lamellar layer at the junctions) at, or slightly above, the valve floor. These constitute criteria by which many species previously assigned to Parastrophinella are excluded from the genus. Late Ordovician species that fit the redefinition of Parastrophinella are now confined to eastern North America. The genus crosses the Ordovician/Silurian boundary without major morphologic change, and Early Silurian species of Parastrophinella occur in both eastern North America and Great Britain. In the Late Ordovician, the pentamerid fauna of North America (Laurentia) contrasted sharply with that of Baltica and Kazakhstan, where the Holorhynchus fauna was dominant. Typical elements of the Holorhynchus fauna, such as the large-shelled Holorhynchus and Proconchidium, are known only in the northern parts of Laurentia (Baffin Island, Greenland, and Kolyma), and are absent in the Hudson Bay and Williston basins and southwards.

Systematics of some Late Ordovician encrinurine trilobites from Laurentian North America

2014 ◽  
Vol 88 (6) ◽  
pp. 1095-1119
Author(s):  
David K. Moss ◽  
Stephen R. Westrop
Keyword(s):  
New Species ◽  
North America ◽  
Species Composition ◽  
Phylogenetic Relationships ◽  
Type Species ◽  
Late Ordovician ◽  
Parsimony Analysis ◽  
Archival Material ◽  
Species Membership

Classification and relationships of the Ordovician encrinurines Frencrinoides Lespérance and Desbiens and Walencrinoides Lespérance and Desbiens are poorly understood, with little evidence for monophyly of either genus. We revise the type species of both genera, F. capitonis (Frederickson) and W. rarus (Walcott), using new and archival material. We explore their species composition and phylogenetic relationships with a parsimony analysis that includes 17 well-documented ingroup species that can be coded readily, and which is rooted with Encrinuroides regularis Parnaste, the oldest known encrinurine. The results support monophyly of Frencrinuroides and Walencrinuroides, albeit with more limited species membership than proposed by Lespérance and Desbiens. Previous suggestions that both E. uncatus Evitt and Tripp and E. neuter Evitt and Tripp should be assigned to Erratencrinurus Kruger are also supported by our analysis, as is monophyly of Physemataspis Evitt and Tripp. New species are W. rolfi and W. tremblayi.

Evolution of the late Ordovician orthid brachiopod Gnamptorhynchos Jin, 1989 from Platystrophia King, 1850, in North America

2000 ◽  
Vol 74 (6) ◽  
pp. 983-991
Author(s):  
Jisuo Jin ◽  
Renbin Zhan
Keyword(s):  
New Species ◽  
North America ◽  
Mass Extinction ◽  
Type Species ◽  
Late Ordovician ◽  
Red River ◽  
Lower Range ◽  
Cardinal Process ◽  
Senior Synonym ◽  
Morphological Intermediate

Gnamptorhynchos, a rhynchonellid-like orthid brachiopod, evolved from Platystrophia in Maysvillian (early Ashgill) time, and survived both the end-Richmondian and end-Hirnantian episodes of the latest Ordovician mass extinction. The name of the type species of Gnamptorhynchos, G. inversum Jin, 1989, is rejected and replaced by Gnamptorhynchos globatum (Twenhofel, 1928), which is a senior synonym. Gnamptorhynchos manitobensis new species is described here from the Selkirk Member (Maysvillian) of the Red River Formation, southern Manitoba. The new species is characterized by a transversely extended, strongly biconvex to globular shell with prominent umbones, relatively numerous costae and a notothyrial cavity supported dorsally by a short median ridge. It constituted part of a Late Ordovician epicontinental fauna that once spread widely in shallow, equatorial seas of North America. The new species is a morphological intermediate between Platystrophia and Gnamptorhynchos, with Platystrophia-like interareas, hingeline, and cardinal process, but Gnamptorhynchos-like shell posterior and notothyrial platform. Previously, Gnamptorhynchos was known from Hirnantian to mid-Aeronian rocks. The new species extends the lower range of the genus to Maysvillian.

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