Chromosome pairing affinities between Old and New World species of Bromus section Pnigma

1984 ◽  
Vol 62 (3) ◽  
pp. 581-585 ◽  
Author(s):  
K. C. Armstrong
Keyword(s):  
Chromosome Pairing ◽  
Interspecific Hybrids ◽  
New World ◽  
Genetic Factors ◽  
Low Frequency ◽  
World Species ◽  
The North ◽  
Evolutionary Pathways ◽  
Bromus Benekenii ◽  
Eurasian Species

A low frequency of allosyndetic chromosome pairing occurred in interspecific hybrids between species having large chromosomes (Bromus benekenii (Lange) Trimen, 2n = 4x = 28; B. ramosus Huds., 2n = 4x = 28; B. pacificus Shear, 2n = 4x = 28) and species having small chromosomes (B. erectus Huds., 2n = 4x = 28; B. inermis Leyss, 2n = 4x = 28; B. pumpellianus Scribn., 2n = 4x = 28; B. riparius Rehm, 2n = 10x = 70; and B. variegatus, 2n = 2x = 14). These results are consistent with the suggestion that the large (predominantly Eurasion) and small (predominantly American) chromosome species of section Pnigma have followed different evolutionary pathways. Chromosome pairing in interspecific hybrids revealed low affinities between the chromosomes of the Eurasian species B. ramosus and the North American species B. pacificus. Thus there was no evidence that B. ramosus contained a form of the L genome found in American species. However genetic factors suppressing homoeologous pairing could be present in the allotetraploid parents.

Megantereon cultridens (Cuvier) (Mammalia, Felidae, Machairodontinae) from Plio-Pleistocene deposits in Africa and Eurasia, with comments on dispersal and the possibility of a New World origin

1987 ◽  
Vol 61 (6) ◽  
pp. 1256-1268 ◽  
Author(s):  
Alan Turner
Keyword(s):  
North America ◽  
North American ◽  
New World ◽  
Single Species ◽  
North American Species ◽  
Junior Synonym ◽  
The North ◽  
Eurasian Species ◽  
Area Of Origin

African machairodont specimens previously referred to three species of Megantereon are considered to represent a single species in turn argued to be conspecific with the Eurasian species Megantereon cultridens (Cuvier). The area of origin of Megantereon remains unclear, but doubt is expressed about claims for an earliest appearance of the genus in North America. It is probable that the North American species M. hesperus is a junior synonym of M. cultridens.

NEW SPECIES AND RECORDS OF NEW WORLD MICROPEPLIDAE (COLEOPTERA). II

1978 ◽  
Vol 110 (12) ◽  
pp. 1247-1258 ◽  
Author(s):  
J. M. Campbell
Keyword(s):  
Latin America ◽  
New Species ◽  
North American ◽  
New World ◽  
North American Species ◽  
World Species ◽  
The North ◽  
The Family ◽  
Three New Species

AbstractThree new species of Micropeplidae are described from Latin America, Micropeplus newtoni from Mexico, Peplomicrus mexicanus from Mexico, and Peplomicrus pecki from Colombia, bringing the total number of New World species to 21. A revised key to aid in the identification of the Micropeplidae of Latin America is presented. New distributional data are given for 10 other species of the family and revised distributional maps are given for the North American species Micropeplus sculptus, M. laticollis, and M. robustus.

A new combination in Alkekengi (Solanaceae) for the Flora of China

Phytotaxa ◽  
2014 ◽  
Vol 178 (1) ◽  
pp. 59 ◽  
Author(s):  
Ruijiang Wang
Keyword(s):  
Vascular Plants ◽  
New World ◽  
Phylogenetic Analyses ◽  
New Combination ◽  
Monotypic Genus ◽  
World Species ◽  
Nomenclature Committee ◽  
Flora Of China ◽  
The Family ◽  
Eurasian Species

The genus Physalis Linnaeus (1753: 182) is a medium-sized genus in the family Solanaceae Jussieu (1789: 124). It includes about 75 New World species and one Eurasian species, P. alkekengi Linnaeus (1753: 183), the generic lectotype (Britton & Brown 1913). Recently, several phylogenetic analyses focusing on Physalis and related taxa strongly supported the monophyly of the morphologically typical New World species, characterized by unlobed and yellow flowers. Physalis alkekengi represents a divergent clade characterized by somewhat lobed, white corollas and brilliant red-orange fruiting calyces (Whitson & Manos 2005; Olmstead et al. 2008). In order to emphasize the monophyly and morphological homogeneity of the New World species and decrease nomenclatural disruption, the genus Physalis was proposed for conservation with a conserved type, P. pubescens Linneaus, to represent the New World species (Whitson 2011). The Eurasian P. alkekengi was suggested to be placed in a monotypic genus Alkekengi Miller (1754: AL) typified with A. officinarum Moench (1802: 177). This proposal was subsequently recommended for acceptance by the Nomenclature Committee for Vascular Plants (Applequist 2012).

scholarly journals A Low frequency Southern Sky Survey Using the Mauritius Radio Telescope

2002 ◽  
Vol 199 ◽  
pp. 25-31
Author(s):  
N. Udaya Shankar
Keyword(s):  
Radio Telescope ◽  
Low Frequency ◽  
Fourier Synthesis ◽  
North East ◽  
The North ◽  
Sky Survey ◽  
Correlation Receiver ◽  
Complex Correlation ◽  
Right Ascension ◽  
East West

The Mauritius Radio Telescope (MRT) is a Fourier synthesis instrument which has been built to fill the gap in the availability of deep sky surveys at low radio frequencies in the southern hemisphere. It is situated in the north-east of Mauritius at a southern latitude of 20°.14 and an eastern longitude of 57°.73. The aim of the survey with the MRT is to contribute to the database of southern sky sources in the declination range −70° ≤ δ ≤ −10°, covering the entire 24 hours of right ascension, with a resolution of 4' × 4'.6sec(δ + 20.14°) and a point source sensitivity of 200 mJy (3σ level) at 151.5 MHz.MRT is a T-shaped non-coplanar array consisting of a 2048 m long East-West arm and a 880 m long South arm. In the East-West arm 1024 fixed helices are arranged in 32 groups and in the South arm 16 trolleys, with four helices on each, which move on a rail are used. A 512 channel, 2-bit 3-level complex correlation receiver is used to measure the visibility function. At least 60 days of observing are required for obtaining the visibilities up to the 880 m spacing. The calibrated visibilities are transformed taking care of the non-coplanarity of the array to produce an image of the area of the sky under observation.This paper will describe the telescope, the observations carried out so far, a few interesting aspects of imaging with this non-coplanar array and present results of a low resolution survey (13' × 18') covering roughly 12 hours of right ascension, and also present an image with a resolution of 4' × 4'.6sec(δ + 20.14°) made using the telescope.

The New World fauna of the genus Pseudonapomyza (Diptera: Agromyzidae)

2004 ◽  
Vol 136 (6) ◽  
pp. 781-791 ◽  
Author(s):  
Stéphanie Boucher
Keyword(s):  
Costa Rica ◽  
New World ◽  
World Species ◽  
First Time ◽  
World Fauna ◽  
Nearctic Region

AbstractThe New World species of Pseudonapomyza Hendel are reviewed. Only two species of the genus were previously known to occur in the Nearctic region: P. atra (Meigen) and P. lacteipennis (Malloch). Pseudonapomyza europaea Spencer and P. asiatica Spencer are here recorded for the first time in the Nearctic region and P. asiatica is recorded for the first time in Costa Rica and Venezuela. A key is provided to identify the four known New World species of Pseudonapomyza.

Low Frequency of Genetic Factors Gm(s) and Di(a) in Finland

1969 ◽  
Vol 19 (2) ◽  
pp. 180-184 ◽  
Author(s):  
Anja Tiilikainen ◽  
E. Ruoslahti ◽  
M. Seppälä ◽  
L. Mårtensson ◽  
Erna Van Loghem
Keyword(s):  
Genetic Factors ◽  
Low Frequency

Marchantia L. the New World Species

Taxon ◽  
1985 ◽  
Vol 34 (4) ◽  
pp. 740
Author(s):  
Barbara M. Thiers ◽  
H. Bischler
Keyword(s):  
New World ◽  
World Species

Three new Nearctic species of Telenomus (Hymenoptera: Scelionidae) attacking Tabanidae eggs

2004 ◽  
Vol 136 (1) ◽  
pp. 43-60 ◽  
Author(s):  
Mahmood Iranpour ◽  
Terry D. Galloway
Keyword(s):  
New Species ◽  
New World ◽  
Egg Parasitoids ◽  
Identification Key ◽  
Type Specimens ◽  
World Species ◽  
Diagnostic Characters ◽  
Three New Species

AbstractThree new species of Tabanidae egg parasitoids are described: Telenomus hybomitraesp. nov. and Telenomus utilissp. nov., both reared from eggs of Hybomitra nitidifrons nuda (McDunnough) and Hybomitra lasiophthalma Macquart, and Telenomus chrysopsissp. nov., reared from eggs of Chrysops aestuans Wulp, Chrysops excitans Walker, and Chrysops mitis Osten Sacken. Specimens of these species were compared with type specimens of known New World species of scelionid parasitoids attacking tabanid eggs. Diagnostic characters and identification key to the Nearctic species are provided.

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