Isoetes × truncata: a newly considered pentaploid hybrid from western North America

1993 ◽  
Vol 71 (8) ◽  
pp. 1016-1025 ◽  
Author(s):  
Donald M. Britton ◽  
Daniel F. Brunton

Three Isoetes found in Pyramid Lake, Jasper National Park, Alberta, constitute populations of tetraploid (2n = 44)I. maritima, hexaploid (2n = 66)I. occidentalis, and an abortive-spored, pentaploid hybrid (2n = 55) with intermediate morphological characteristics. Although the hybrid has been present in the lake since at least 1918, I. maritima and I. occidentalis were previously unknown in Alberta. The presence of these aquatics hundreds of kilometres from their next known populations in central British Columbia is suspected to reflect the floristic and faunal affinity of the Pyramid Lake area to biotic regions in the interior of British Columbia. Morphological, scanning electron microscopy, and cytological data are provided to support our conclusion that the Alaskan type material of I. × truncata is synonymous with the Pyramid Lake pentaploid. Investigations of similar taxa in western North America detected several I. occidentalis populations in Alaska where it was previously unknown. This represents the first report of a pentaploid Isoetes hybrid in North America and the first western North American hybrid to be described in detail. Key words: Isoetes, Isoetes maritima, Isoetes occidentalis, Isoetes × truncata, hybrid, Alberta, Alaska.

1990 ◽  
Vol 22 (3) ◽  
pp. 205-212 ◽  
Author(s):  
T. Tønsberg

AbstractThe genus Japewia Tønsb. is introduced to accommodate three species including J. subaurifera Muhr & Tønsb. sp. nov. based on material from Norway, Sweden, Finland, Scotland, Canada (British Columbia) and U.S.A. (Washington). This species is closely related to Lecidea tornoensis Nyl. but is distinguished in being sorediate and by the production of lobaric acid (accessory) and acetone-soluble pigments. It grows on bark of deciduous and coniferous trees. Lecidea carrollii Coppins & P. James and L. tornoensis Nyl. are transferred to Japewia.


1989 ◽  
Vol 26 (8) ◽  
pp. 1612-1616 ◽  
Author(s):  
T. P. Poulton ◽  
J. D. Aitken

Sinemurian phosphorites in southeastern British Columbia and southwestern Alberta conform with the "West Coast type" phosphorite depositional model. The model indicates that they were deposited on or near the Early Jurassic western cratonic margin, next to a sea or trough from which cold water upwelled. This suggests that the allochthonous terrane Quesnellia lay well offshore in Sinemurian time. The sea separating Quesnellia from North America was partly floored by oceanic crust ("Eastern Terrane") and partly by a thick sequence of rifted, continental terrace wedge rocks comprising the Purcell Supergroup and overlying Paleozoic sequence. This sequence must have been depressed sufficiently that access of upwelling deep currents to the phosphorite depositional area was not impeded.


2015 ◽  
Vol 89 (1) ◽  
pp. 82-95 ◽  
Author(s):  
Steven T. LoDuca ◽  
Jean-Bernard Caron ◽  
James D. Schiffbauer ◽  
Shuhai Xiao ◽  
Anthony Kramer

AbstractTo investigate the phylogenetic affinity of Yuknessia simplex Walcott, 1919, scanning electron microscopy was applied to the Burgess Shale (Cambrian Series 3, Stage 5) type material and to new material from the Trilobite Beds (Yoho National Park) and specimens from the Cambrian of Utah. On the basis of fine-scale details observed using this approach, including banding structure interpreted as fusellae, Yuknessia Walcott, 1919 is transferred from the algae, where it resided for nearly a century, to the extant taxon Pterobranchia (Phylum Hemichordata). Considered as such, Yuknessia specimens from the Trilobite Beds and Spence Formation (Utah) are amongst the oldest known colonial pterobranchs. Two morphs regarded herein as two different species are recognized from the Trilobite Beds based on tubarium morphology. Yuknessia simplex has slender erect tubes whereas Yuknessia stephenensis n. sp., which is also known in Utah, has more robust erect tubes. The two paratypes of Y. simplex designated by Walcott (1919) are formally removed from Yuknessia and are reinterpreted respectively as an indeterminate alga and Dalyia racemata Walcott, 1919, a putative red alga.


1943 ◽  
Vol 75 (8) ◽  
pp. 139-145 ◽  
Author(s):  
Charles P. Alexander

The crane-flies considered herewith are all from Western North America, from British Columbia to California. The names of the collectors and the location of the type material are indicated at the end of the individual specific accounts; where not stated to the contrary, such types are preserved in my own collection of these flies.


1964 ◽  
Vol 21 (5) ◽  
pp. 933-939 ◽  
Author(s):  
Richard H. Rosenblatt

A new species, Pholis clemensi, referred to the family Pholidae, is named and described from 12 specimens taken in southern British Columbia waters and the Strait of Juan de Fuca. Pholis clemensi is compared with other members of the genus, and a key is given to the North American species.


Zootaxa ◽  
2021 ◽  
Vol 4908 (2) ◽  
pp. 205-224
Author(s):  
WILLIAM A. SHEAR

The millipede genus Amplaria Chamberlin, 1941 (senior synonym of Vaferaria Causey, 1958 and Speostriaria Causey, 1960) is endemic to western North America, from Mt. Palomar and San Luis Obispo, California, north to southwestern British Columbia, Canada, and east to northern Idaho. Seven species names are currently assigned to the genus. Below I describe ten additional new species: Amplaria crawfordi, Amplaria fontinalis, Amplaria rykkenae, Amplaria arcata, Amplaria baughi, Amplaria staceyi, Amplaria umatilla, Amplaria cervus, Amplaria mendocino and Amplaria flucticulus, and provide new records of Amplaria nazinta Chamberlin. 


2004 ◽  
Vol 62 (1) ◽  
pp. 94-104 ◽  
Author(s):  
M.A. Lanphere ◽  
D.E. Champion ◽  
M.A. Clynne ◽  
J.B. Lowenstern ◽  
A.M Sarna-Wojcicki ◽  
...  

The age of the Rockland tephra, which includes an ash-flow tuff south and west of Lassen Peak in northern California and a widespread ash-fall deposit that produced a distinct stratigraphic marker in western North America, is constrained to 565,000 to 610,000 yr by 40Ar/39Ar and U–Pb dating. 40Ar/39Ar ages on plagioclase from pumice in the Rockland have a weighted mean age of 609,000 ± 7000 yr. Isotopic ages of spots on individual zircon crystals, analyzed by the SHRIMP-RG ion microprobe, range from ∼500,000 to ∼800,000 yr; a subpopulation representing crystal rims yielded a weighted-mean age of 573,000 ± 19,000 yr. Overall stratigraphic constraints on the age are provided by two volcanic units, including the underlying tephra of the Lava Creek Tuff erupted within Yellowstone National Park that has an age of 639,000 ± 2000 yr. The basaltic andesite of Hootman Ranch stratigraphically overlies the Rockland in the Lassen Peak area and has 40Ar/39Ar ages of 565,000 ± 29,000 and 565,000 ± 12,000 yr for plagioclase and groundmass, respectively. Identification of Rockland tephra in ODP core 1018 offshore of central California is an important stratigraphic age that also constrains the eruption age to between 580,000 and 600,000 yr.


2019 ◽  
Vol 56 (8) ◽  
pp. 803-813
Author(s):  
Gerald Mayr ◽  
S. Bruce Archibald ◽  
Gary W. Kaiser ◽  
Rolf W. Mathewes

We survey the known avian fossils from Ypresian (early Eocene) fossil sites of the North American Okanagan Highlands, mainly in British Columbia (Canada). All specimens represent taxa that were previously unknown from the Eocene of far-western North America. Wings from the McAbee site are tentatively referred to the Gaviiformes and would constitute the earliest fossil record of this group of birds. A postcranial skeleton from Driftwood Canyon is tentatively assigned to the Songziidae, a taxon originally established for fossils from the Ypresian of China. Two skeletons from Driftwood Canyon and the McAbee site are tentatively referred to Coliiformes and Zygodactylidae, respectively, whereas three further fossils from McAbee, Blakeburn, and Republic (Washington, USA) are too poorly preserved for even a tentative assignment. The specimens from the Okanagan Highlands inhabited relatively high paleoaltitudes with microthermal climates (except Quilchena: lower mesothermal) and mild winters, whereas most other Ypresian fossil birds are from much warmer lowland paleoenvironments with upper mesothermal to megathermal climates. The putative occurrence of a gaviiform bird is particularly noteworthy because diving birds are unknown from other lacustrine Ypresian fossil sites of the Northern Hemisphere. The bones of the putative zygodactylid show a sulphurous colouration, and we hypothesize that this highly unusual preservation may be due to the metabolic activity of sulphide-oxidizing bacteria.


1982 ◽  
Vol 60 (8) ◽  
pp. 1512-1522 ◽  
Author(s):  
Rubén Durán

Five new species of Thecaphora collected in Mexico are described, some of which are parasitic on genera of Compositae not previously reported as hosts. Species of Thecaphora on Compositae for the North American continent now total 11. New species include Thecaphora denticulata, T. heliopsidis, T. hennenea, T. melampodii, and T. neo-mexicana. New host genera for North America include Bidens, Heliopsis, and Melampodium. Morphological characteristics of Thecaphora species and taxonomic criteria to delimit them are discussed. Keys to the species, interpretations of spore ball morphology and spore sculpturing, and scanning electron and bright-field micrographs are presented.


1984 ◽  
Vol 62 (7) ◽  
pp. 1387-1396
Author(s):  
James E. O'Hara

Baeomyia n.g. is described for a group of small (2–3 mm long) tachinids belonging to the Siphona group of the Siphonini. All known specimens were collected in western North America, with two species recorded from southern British Columbia (Baeomyia xanthogaster n. sp. and Baeomyia juniperi n. sp.) and three species recorded from desert localities in the American Southwest (type-species Baeomyia hurdi (Reinhard), Baeomyia antennata n. sp. and Baeomyia sonorensis n. sp.). Keys to adult males and females are provided for separation of species. Systematics of the Siphonini and Siphona group are reviewed, including a discussion of the synapomorphies upon which each is defined. Baeomyia species are inferred to form a monophyletic taxon within the Siphona group on the basis of five synapomorphies, though the relationship between the genus and other Siphona group taxa is unresolved. The apparent disjunction of Baeomyia species into northern and southern ranges may be the result of relatively recent speciation events, because differences among species are slight. A detailed zoogeographic analysis of the distribution pattern must await further phylogenetic data.


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