The taxonomic status of Timmia sibirica

1981 ◽  
Vol 59 (5) ◽  
pp. 563-571 ◽  
Author(s):  
Diana G. Horton

A critical study of the differentiating features of the North American populations of Timmia sibirica Lindb. et Arnell and T. norvegica Zett. reveals that populations with structure intermediate between these two taxa occur. Although from widespread localities, the intermediate specimens seem limited in number and T. sibirica and T. norvegica quite commnonly occur in mixed populations with no evidence of any intergradation. Therefore, it is concluded that the two taxa ought to be regarded as distinct species. The taxonomically important character-states of upper leaf cells and costa of T. sibirica. T. norvegica, and of the intermediate populations are illustrated with scanning elecron micrographs. The habitat of T. sibirica, like that of T. norvegica, is invariably on strongly calcareous substrates adjacent to waterfalls, along streams, or in low-lying tundra. The North American distribution of T. sibirica is mapped, including previously unreported localities as far south as 51° N in the Canadian Rocky Mountains.

2006 ◽  
Vol 84 (3) ◽  
pp. 453-468 ◽  
Author(s):  
Chang-Shook Lee ◽  
Stephen R. Downie

The genus Cicuta (Apiaceae tribe Oenantheae Dumort.) is the most virulently poisonous group of flowering plants native to the north temperate zone. A recent treatment recognized four species ( C. bulbifera L., C. douglasii (DC.) J.M. Coult. & Rose, C. maculata L., and C. virosa L.), with C. maculata divided into four varieties. We present results of phylogenetic analyses of the nuclear ribosomal DNA (rDNA) internal transcribed spacer (ITS) locus and the region bounded by the chloroplast genes psbI and trnK 5′ exon to determine taxonomic limits and relationships among these taxa, and to assess the taxonomic status of C. douglasii, a polyploid thought to be derived from C. maculata and C. virosa. Cicuta bulbifera and C. virosa are each resolved as monophyletic, the latter is a sister group to all other species. Discordance between the ITS- and plastid-derived phylogenies and lack of resolution in the ITS trees preclude unequivocal hypotheses of relationship; all trees do suggest, however, that the allotetraploid C. douglasii is polyphyletic and possibly polytopic, with all examined accessions but one nested within C. maculata. This single outstanding accession is from California and, pending further study, might warrant recognition as a distinct species. The diploid C. bulbifera may also be of hybrid origin, as revealed by significant discordance between data sets. Within C. maculata, only the western North American var. angustifolia Hook. is resolved in the ITS trees. In the cpDNA trees, C. maculata var. angustifolia comprises a strongly supported clade with C. maculata var. bolanderi (S. Watson) G.A. Mulligan and C. douglasii, both of primarily western North American distribution. The eastern North American taxa, C. maculata vars. maculata and victorinii (Fernald) B. Boivin, also comprise a clade, sister group to C. bulbifera.


1957 ◽  
Vol 89 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Stephen L. Wood

While investigating the biology of the North American species of Hypomolyx, field workers in Manitoba found a vestigial, or short-winged, and a long-winged form under apparently identical conditions in about equal numbers. Although biological differences were nor then apparent, there was doubt as to whether they were dealing with one dimorphic species or with two distinct species, A search for morphological characters brought to light numerous differences between the two forms, supporting the view that two species were present. These differences, a description the previously unrecognized species, and notes concerning the status of the genera Hylobius and Hypomolyx are reported below.


1987 ◽  
Vol 24 (8) ◽  
pp. 1688-1704 ◽  
Author(s):  
Russell L. Hall

New ammonite faunas are described from sections along Bighorn and Scalp creeks in central-western Alberta where Lower Jurassic parts of the Fernie Formation are exposed. The first record of the upper Sinemurian Obtusum Zone from the Fernie is based on the occurrence of Asteroceras cf. stellare and Epophioceras cf. breoni in the basal pebbly coquina on Bighorn Creek. The overlying Red Deer Member has yielded Amaltheus cf. stokesi, representing the upper Pliensbachian Margaritatus Zone; in immediately superjacent strata the first North American examples of ?Amauroceras occur together with Protogrammoceras and ?Aveyroniceras. In the basal parts of the overlying Poker Chip Shale a fauna including Harpoceras cf. falciferum, Harpoceratoides, Polyplectus cf. subplanatus, Hildaites cf. serpentiniformis, and Dactylioceras cf. athleticum is correlated with the lower Toarcian Falciferum Zone.The upper parts of the Poker Chip Shale on Fording River in southeastern British Columbia contain a fauna representing some part of the upper Toarcian, but owing to poor preservation, generic identifications are only tentatively made.


2009 ◽  
Vol 13 (1) ◽  
pp. 25-30 ◽  
Author(s):  
Oksana Yavorska

The North American species of the non-native flora of the Kyiv urban area (Ukraine): a checklist and analysisThis paper presents an annotated checklist of the North American species established in the flora of the Kyiv urban area (KUA). For each taxon, the following data are provided: distribution in the area, degree of naturalization, period of immigration, mode of immigration and ecological characteristics. The group of the North American neophytes consists of 114 species belonging to 71 genera and 36 families and 23 cultivated species and of problematic taxonomic status. Among them prevail ergasiophytes (26%), ergasiophygophytes (22%) and ephemerophytes (19%). The majority of neophytes (47%) have spread over all types of ecotopes. Among them 12 species are invasive alien plants in the KUA.


1999 ◽  
Vol 36 (8) ◽  
pp. 1281-1298 ◽  
Author(s):  
Lauret E Savoy ◽  
Anita G Harris ◽  
Eric W Mountjoy

Uppermost Devonian and Lower Mississippian strata in the Rocky Mountains of southwestern Canada and northwestern Montana record widespread oceanographic changes during middle to late Paleozoic time associated with the termination of a carbonate ramp system, the onset of a deep-water, low-oxygen event and possible marginal tectonism, and the later reestablishment of a carbonate ramp. Integrated lithofacies and conodont biofacies developed previously for these strata between the Bow Valley and the international border have been extended northward to the Athabasca region of the Alberta Rocky Mountains. During early-middle Famennian time, the southern Canadian Rocky Mountains region was the site of a westward-deepening and westward-thickening carbonate ramp system (Palliser Formation). By late Famennian time carbonate ramp deposition ended and was followed by widespread deposition of organic-rich, low-oxygen facies in shelf to basinal environments (Exshaw Formation and correlative units). The overlying Banff Formation consists of anaerobic to marginally aerobic, starved-basin to deep-ramp lithofacies succeeded by shallower water carbonates; this sequence records basinward (westward) progradation of the Banff ramp in middle to late Tournaisian time. Distinct conodont biofacies representative of shallow-ramp to deep-basin settings that were previously recognized in the southernmost Canadian Rocky Mountains and Montana have also been identified to the north between the North Saskatchewan and Athabasca valleys. Upper Palliser carbonates contain low-diversity conodont faunas of indigenous to transported palmatolepid-, polygnathid-, and apatognathid-dominated assemblages. Exshaw deposits contain indigenous and reworked palmatolepid- and bispathodid-dominated assemblages and reworked or transported polygnathids. Lower Banff biofacies include transported and indigenous assemblages of siphonodellids, polygnathids, and pseudopolygnathids representative of the deep-middle Banff ramp. Polygnathid-hindeodid biofacies of shallower middle-ramp environments occur higher in the Banff Formation in the North Saskatchewan and Athabasca valleys.


1906 ◽  
Vol 38 (8) ◽  
pp. 269-272 ◽  
Author(s):  
Chas. Schaeffer

Working over some neglected material, I found, to my surprise, that the specimens of Ochodœus colleted by me last year in Arizona are separable into three distinct species, none of which agree with the descriptions of the North American species. A few years ago my brother sent me from California, with some other material, two specimens of what I take to be an Ochadœus. Unfortunately, I misplaced one of the specimens, and not wishing to dissect the single remaining one, I leave this species in this genus for the present, till more material is available.


1979 ◽  
Vol 57 (3) ◽  
pp. 269-283 ◽  
Author(s):  
Dale H. Vitt ◽  
Diana G. Horton

The Nahanni and Liard mountain ranges are located at about 61° N latitude and 122° W longitude. They form the easternmost slopes of the Rocky Mountains and lie just east of Nahanni National Park in the southwestern corner of the District of Mackenzie, Northwest Territories. The moss flora of the area is rich in the number of taxa; 207 species and two varieties are reported from this relatively small area. Of these, 53 species are new records for the South Nahanni region. A number of rare or disjunct bryophyte species are found in the area. Moss species which are either disjunct or occur at the edge of their range include Arctoa fulvella (Dicks.) B.S.G., Aulacomnium acuminatum (Lindb. & Arn.) Kindb., Andreaeobryum macrosporum Steere & B. Murray, Geheebia gigantea (Funck) Boul., Isopterygiopsis muelleriana (Schimp.) Iwats., Mnium spinosum (Voit) Schwaegr., Psilopilum cavifolium (Wils.) Hagen, Rhabdoweisia crispata (With.) Lindb., Seligeria calcarea (Hedw.) B.S.G., S. polaris Berggr., Trematodon brevicollis Hornsch., and Trichostomum arcticum Kaal. The North American distribution of these species is mapped. Herbertus stramineus (Dum.) Trev., Metacalypogeia schusterana Hatt. & Mizut., Scapania crassiretis Bryhn, and S. simmonsii Bryhn & Kaal. are four hepatic species of phytogeographic interest.


2000 ◽  
Vol 132 (4) ◽  
pp. 411-427 ◽  
Author(s):  
Joëlle R. Pérusse ◽  
Terry A. Wheeler

AbstractThe North American species of Lauxania Latreille are revised. The genus contains five Nearctic species: L. albiseta Coquillett, L. glabrifronssp.nov., L. kafaristasp.nov., L. nigrimana Coquillett, and L. shewellisp.nov. All Nearctic species are illustrated and keyed. Consistent genitalic differences between Nearctic and Palaearctic specimens of the species usually identified as Lauxania cylindricornis (Fabricius) justify the recognition of the Nearctic specimens as a distinct species (L. shewelli). The male genitalia of Lauxania represent two types: the apparently plesiomorphic type has a simple rodlike phallapodeme, membranous phallus, and pointed unbranched postgonites; the apomorphic type has the phallapodeme expanded into a sclerotized hood surrounding the base of the phallus, a convoluted sclerotized phallus, and branched postgonites. These two genitalic types also occur in the related genus Calliopum Strand, which provides strong evidence that these genera, as currently recognized, may not be monophyletic relative to one another.


1887 ◽  
Vol 19 (10) ◽  
pp. 181-191 ◽  
Author(s):  
H. H. Lyman

The North American species of the genus Callimorpha are exceedingly interesting both from their beauty and from the extreme variations to which some of the species are subject, and which has given rise not only tot he creation of numerous synonyms, but also to distinct species being regarded as merely varieties of other forms.


1965 ◽  
Vol 97 (2) ◽  
pp. 159-172 ◽  
Author(s):  
G. R. Hopping

AbstractGroup VIII of North American Ips contains I. interruptus (Mannerheim), I. engelmanni Swaine, I. amiskwiensis G. Hopping, I. sulcifrons Wood, I. pilifrons Swaine, I. yohoensis Swaine, I. tridens (Mannerheim) and I. semirostris G. Hopping. Females of some species have dense brushes of long setae or pads of short pile covering the frontal protuberance. Species are described and a key is given. All of them breed in spruce, six in the boreal forest and two farther south in the Rocky Mountains.


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