scholarly journals Agave dealbata E.Morren ex K.Koch (Asparagaceae), the correct name for Agave dasylirioides Jacobi & C.D.Bouché (Nomenclature of Agave L. I) 

Phytotaxa ◽  
2014 ◽  
Vol 163 (5) ◽  
pp. 295 ◽  
Author(s):  
Joachim Thiede
Keyword(s):  
North America ◽  
New Taxa ◽  
Multiple Introductions ◽  
Author Citations

The genus Agave Linné (1753: 323; Asparagaceae-Agavoideae) has played an important role for the indigenous civilizations of North America (“man-Agave symbiosis”) and is of considerable economical and horticultural importance (Gentry 1982). Many new Agave species were introduced between about 1860 and 1890 particularly from Mexico. Frequently, new taxa have a complicated nomenclatural history with often multiple introductions or descriptions by different, partly competing authors and in publications often difficult to access (e.g., Govaerts & Thiede 2013). This has led to a considerable number of incorrect author citations and/or places of publication in taxonomic treatments as well as databases such as IPNI (2013). In the framework of a second, updated edition of a taxonomic synopsis of Agave (Thiede, in prep.), at least some uncertain and controversial nomenclatural issues will need to be addressed, starting here with A. dealbata. 

scholarly journals Multiple Introductions of the Old World Begomovirus Tomato yellow leaf curl virus into the New World

2007 ◽  
Vol 73 (21) ◽  
pp. 7114-7117 ◽  
Author(s):  
Siobain Duffy ◽  
Edward C. Holmes
Keyword(s):  
North America ◽  
New World ◽  
Tomato Yellow Leaf ◽  
Yellow Leaf ◽  
Old World ◽  
Multiple Introductions ◽  
The Caribbean ◽  
Genomic Regions ◽  
Leaf Curl Virus ◽  
Leaf Curl

ABSTRACT A phylogenetic analysis of three genomic regions revealed that Tomato yellow leaf curl virus (TYLCV) from western North America is distinct from TYLCV isolated in eastern North America and the Caribbean. This analysis supports a second introduction of this Old World begomovirus into the New World, most likely from Asia.

Wild proso millet (Panicum miliaceum) is genetically variable and distinct from crop varieties of proso millet

Weed Science ◽  
1997 ◽  
Vol 45 (4) ◽  
pp. 509-518 ◽  
Author(s):  
Joseph C. Colosi ◽  
Barbara A. Schaal
Keyword(s):  
Genetic Variation ◽  
North America ◽  
Genetic Relationships ◽  
Random Amplified Polymorphic Dna ◽  
Large Area ◽  
Row Crops ◽  
Multiple Introductions ◽  
Proso Millet ◽  
Crop Varieties ◽  
Two Hybrid

Proso millet occurs both as a crop and a weed in North America. In 1970, an olive-black seeded biotype called ‘wild proso millet’ was found as an aggressive weed in row crops in Minnesota and Wisconsin and has since spread over a large area. We used Random Amplified Polymorphic DNA (RAPD) to assess genetic relationships among biotypes, measure genetic variation within wild proso millet across its range, and detect hybridization between wild proso millet and crop biotypes of proso millet. We found 97 RAPD genotypes among 398 individuals: 69 wild proso millet genotypes, 26 crop and crop-like weed genotypes, and two hybrid genotypes. Five RAPD markers consistently differentiated wild proso millet from crop cultivars and crop-like weeds. About 10% of the genotypes had at least one marker of the other type, suggesting possible hybridization between wild proso millet and crop biotypes. Most genotypes occurred in only one or two of the over 100 populations tested. The most widespread wild proso millet genotype occurred in 12 populations distributed in North Dakota, Minnesota, Illinois, and Wisconsin. More genetic variation exists among populations of wild proso millet than expected for a plant that presumably experienced a severe genetic bottleneck only 20 generations ago. Hypermutation rates and crossing between wild proso millet and crop cultivars could not account for the degree of genetic variation found in wild proso millet. The pattern of genetic variation among wild proso millet populations suggests multiple introductions of wild proso millet to North America.

scholarly journals Molecular evidence for multiple introductions of the banded grove snail (Cepaea nemoralis) in North America

2019 ◽  
Vol 97 (4) ◽  
pp. 392-398 ◽  
Author(s):  
K.K.S. Layton ◽  
C.P.K. Warne ◽  
A. Nicolai ◽  
A. Ansart ◽  
J.R. deWaard
Keyword(s):  
Invasive Species ◽  
North America ◽  
Central Europe ◽  
Coi Gene ◽  
Molecular Evidence ◽  
Eastern Canada ◽  
Multiple Introductions ◽  
Cepaea Nemoralis ◽  
Haplotype Networks ◽  
Base Pair Fragment

Global identification and monitoring programs for invasive species aim to reduce imminent impacts to biodiversity, ecosystem services, agriculture, and human health. This study employs a 658 base pair fragment of the cytochrome c oxidase subunit I (COI) gene to identify and categorize clades of the banded grove snail (Cepaea nemoralis (Linnaeus, 1758)) from native (European) and introduced (North American) ranges using a maximum-likelihood phylogeny and haplotype networks. This work corroborates the existence of eight clades within C. nemoralis and further identified three clades that were common to both Europe and North America (A, D, O). Clades A and D were found in eastern Canada, Ontario (Canada), and British Columbia (Canada), whereas clade O was restricted to Ontario, possibly introduced from Poland or central Europe. Haplotype networks suggest clade A was introduced from northern Europe, whereas clade D was introduced from western and central Europe. Networks contained many private haplotypes and a lack of haplotype sharing, suggesting strong genetic structure in this system, possibly resulting from reduced dispersal in this species. This study describes the contemporary distribution of C. nemoralis in Canada and demonstrates the efficacy of DNA barcoding for monitoring the spread of invasive species, warranting its widespread adoption in management policies.

Palynology of the Ordovician Kanosh Shale at Fossil Mountain, Utah

2015 ◽  
Vol 89 (3) ◽  
pp. 424-447 ◽  
Author(s):  
Marco Vecoli ◽  
John H. Beck ◽  
Paul K. Strother
Keyword(s):  
North America ◽  
Shallow Water ◽  
New Taxa ◽  
Middle Ordovician ◽  
Incomplete Knowledge ◽  
Late Cambrian ◽  
Freshwater Influence ◽  
Depositional Setting ◽  
Biological Differences

AbstractPalynomorph assemblages recovered from the Kanosh Shale at Fossil Mountain, Utah, are dominated by operculate acritarchs and cryptospores with minor smaller acritarchs. The present findings add new data to the largely incomplete knowledge of Ordovician acritarch assemblages from Laurentia, up to now known only from very few localities in North America. These populations contain some species in common with acritarchs from the Canning and Georgina basins in Australia and with assemblages from China; they indicate a Middle Ordovician (Dapingian-Darriwilian) age. The assemblage is lacking many typical marine acritarchs of this age, which, in combination with some cryptospores, is probably reflecting the likelihood of freshwater influence in the Kanosh Basin. This observation is congruent with previous interpretations of the depositional setting of the Kanosh Shale as a shallow water lagoon that supported the deposition of carbonate hardgrounds.Four new taxa are described: Busphaeridium vermiculatum n. gen., n. sp.; Digitoglomus minutum n. gen., n. sp.; Turpisphaera heteromorpha n. gen., n. sp.; and Vermimarginata barbata n. gen., n. sp. In addition, the abundance of operculate forms has enabled the revision and a new emendation of the genus Dicommopalla and clarification of the “opalla” complex. We also propose new and revised suprageneric taxa that emphasize inferred biological differences among acritarch genera. The Sphaeromorphitae subgroup is emended to include forms lacking sculptural elements. Two new informal subgroups are proposed: the Superornamenti and the Operculate Acritarchs. Cryptospores are abundant throughout the sections studied and they appear to be more closely related to the late Cambrian Agamachates Taylor and Strother than to Darriwilian and younger Ordovician cryptospores from Gondwana.

New fossil portunids from Washington, USA, and Argentina, and a re-evaluation of generic and family relationships within the Portunoidea Rafinesque, 1815 (Decapoda: Brachyura)

2000 ◽  
Vol 74 (4) ◽  
pp. 636-653 ◽  
Author(s):  
Carrie E. Schweitzer ◽  
Rodney M. Feldmann
Keyword(s):  
New Species ◽  
North America ◽  
New Taxa ◽  
Family Relationships ◽  
West Coast ◽  
New Genus ◽  
New Combinations ◽  
The West

New portunoid fossils from southern Argentina and from the west coast of North America permit the reevaluation of the generic and family relationships within the Portunoidea Rafinesque, 1815. It has previously been suggested that the Portunidae and the Geryonidae Colosi, 1923, are closely related families (Manning and Holthuis, 1989). The new fossils suggest that the Geryonidae may in fact be derived from a portunid progenitor,ProterocarcinusFeldmann, Casadío, Chirino-Gálvez, and Aguirre Urreta, 1995, through a process of peramorphosis in which juveniles of the geryonid speciesChaceon peruvianus(d'Orbigny, 1842) resemble adults ofProterocarcinus latus(Glaessner, 1933). Examination of several genera within the portunid subfamily Polybiinae Ortmann, 1893, includingImaizumilaKarasawa, 1993;Megokkosnew genus;MinohellenusKarasawa, 1990;PororariaGlaessner, 1980;PortunitesBell, 1858; andProterocarcinus,suggests that the subfamily had an amphitropical distribution early in its history. New taxa reported here includeMegokkosnew genus andPortunites nodosusnew species. New combinations includeChaceon peruvianus(d'Orbigny, 1842),Imaizumila araucana(Philippi, 1887),Megokkos alaskensis(Rathbun, 1926),Megokkos hexagonalis(Nagao, 1932),Megokkos macrospinus(Schweitzer, Feldmann, Tucker, and Berglund, 2000),Minohellenus triangulum(Rathbun, 1926), andProterocarcinus latus(Glaessner, 1933).

New Taxa of Orthotrichum from Western North America

1971 ◽  
Vol 74 (2) ◽  
pp. 159
Author(s):  
Dale H. Vitt
Keyword(s):  
North America ◽  
New Taxa ◽  
Western North America
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