Genus

About: Genus is a research topic. Over the lifetime, 68921 publications have been published within this topic receiving 590966 citations. The topic is also known as: monospecies genus & genus (zoology).

The evolutionary history of Mimosa (Leguminosae): toward a phylogeny of the sensitive plants.

Abstract:  Premise of the study: Large genera provide remarkable opportunities to investigate patterns of morphological evolution and historical biogeography in plants. A molecular phylogeny of the species-rich and morphologically and ecologically diverse genus Mimosa was generated to evaluate its infrageneric classifi cation, reconstruct the evolution of a set of morphological characters, and establish the relationships of Old World species to the rest of the genus.  Methods: We used trnD-trnT plastid sequences for 259 species of Mimosa (ca. 50% of the total) to reconstruct the phylogeny of the genus. Six morphological characters (petiolar nectary, infl orescence type, number of stamens, number of petals, pollen type, and seismonasty) were optimized onto the molecular tree.  Key results: Mimosa was recovered as a monophyletic clade nested within the Piptadenia group and includes the former members of Schrankia , corroborating transfer of that genus to Mimosa . Although we found good support for several infrageneric groups, only one section ( Mimadenia ) was recovered as monophyletic. All but one of the morphological characters analyzed showed high levels of homoplasy. High levels of geographic structure were found, with species from the same area tending to group together in the phylogeny. Old World species of Mimosa form a monophyletic clade deeply nested within New World groups, indicating recent (6 – 10 Ma) long-distance dispersal.  Conclusions: Although based on a single plastid region, our results establish a preliminary phylogenetic framework for Mimosa that can be used to infer patterns of morphological evolution and relationships and which provides pointers toward a revised infrageneric classifi cation.

DNA barcoding of Pacific Canada’s fishes

Abstract: DNA barcoding—sequencing a standard region of the mitochondrial cytochrome c oxidase 1 gene (COI)—promises a rapid, accurate means of identifying animals to a species level. This study establishes that sequence variability in the barcode region permits discrimination of 98% of 201 fish species from the Canadian Pacific. The average sequence variation within species was 0.25%, while the average distance separating species within genera was 3.75%. The latter value was considerably lower than values reported in other studies, reflecting the dominance of the Canadian fauna by members of the young and highly diverse genus Sebastes. Although most sebastids possessed distinctive COI sequences, four species did not. As a partial offset to these cases, the barcode records indicated the presence of a new, broadly distributed species of Paraliparis and the possibility that Paraliparis pectoralis is actually a species pair. The present study shows that most fish species in Pacific Canadian waters correspond to a single, tightly cohesive array of barcode sequences that are distinct from those of any other species, but also highlights some taxonomic issues that need further investigation.

Catalogue of the Cerambycidae (Coleoptera) of the Neotropical Region. Part III. Subfamilies Parandrinae, Prioninae, Anoplodermatinae, Aseminae, Spondylidinae, Lepturinae, Oxypeltinae, and addenda to the Cerambycinae and Lamiinae

Abstract: A catalogue of the subfamilies Parandrinae (two tribes, four genera and 39 species), Prioninae (nine tribes, 83 genera, 309 species and 13 subspecies), Anoplodermatinae (three tribes, 10 genera and 27 species), Aseminae (two tribes, five genera, 18 species and two subspecies), Oxypeltinae (two genera and three species), Spondylidinae (one genus and one species) and Lepturinae (two tribes, 51 genera, 237 species and two subspecies) (Coleoptera: Cerambycidae) of the Neotropical Region is presented. Under each family-group name bibliographical references are given and under each species-group name, data on the type-locality, the acronym of the institution where the type is deposited, the geographical distribution and detailed bibliographical references are provided. In Prioninae, Callipogonini: Anacanthus Audinet-Serville, 1832, preoccupied by Anacanthus Gray, 1830 (Pisces) is substituted by Chorenta Gistel, 1848. In Lepturinae, Lepturini: Euryptera virgata Gounelle, 1911, new status; Necydalini: Platynocera Blanchard, 1851, preoccupied by Platynocera Blanchard, 1847, Coleoptera, Chrysomelidae is substituted by Stenorhopalus Blanchard, 1851. Omissions to Monne (2005a, b) are given in the addenda. The following taxa described before February 2005 were absent and now are included: Cotyachryson inspergatus (Fairmaire & Germain, 1859), new comb. in Achrysonini, Urorcites Thomson, 1878 in Elaphidiini, Areotis Bates, 1867 in Graciliini, Limernaea Thomson, 1878 in Hesperophanini, Trichoplon Martins, 1967 in Ibidionini, Ischasia ecclinusae, I. mareki, I. pouteriae, I. sabatieri, I. viridithorax, Ommata (Ommata) gallardi, Ommata (Eclipta) bauhiniae, O. (E.) giuglarisi, O. (E.) guianensis, O. (E.) kawensis, O. (E.) lauraceae, O. (E.) pilosipes, O. (E.) vasconezi, Ommata (Rhopalessa) durantoni, Phygopoda ingae, in Rhinotragini, all Penaherrera-Leiva & Tavakilian, 2004, Epipodocarpus Bosq, 1951 in Tillomorphini and in Trachyderini, Trachyderina, Vianauragus, new name for Uragus Guerin-Meneville, 1844, not Uragus Keyserling & Blasius, 1840, Aves. The following new names are given, in Achrysonini: Achryson jolyi, new name to replace Achryson concolor Joly, 2000 preoccupied by Achryson concolor LeConte, 1873 (Geropa) and Cerdaia new name to replace Pehuenia Cerda, 1980, preoccupied by Pehuenia Roth, 1902, extinct Mammalia; in Elaphidiini: Anelaphus martinsi, new name to replace Anelaphus fasciatus Martins, 2005, preoccupied by Anelaphus fasciatus (Fisher, 1932); in Rhopalophorini: Rhopaliella new name to replace Rhopalina Monne, 1990, preoccupied by Rhopalina Tinkham, 1939, Orthoptera; in Trachyderini, Trachyderina: Chemsakiella new name to replace Linsleyella Chemsak, 1984, preoccupied by Linsleyella Rohr, 1980, Mollusca, Laneiella new name to replace Pujolia Lane, 1973, preoccupied by Pujolia Levasseur, 1968, Coleoptera, Neomegaderus new name to replace Megaderus Dejean, 1821, preoccupied by Megaderus Rafinesque, 1815, Pisces; in Incertae Sedis: Tippmannia new name to replace Dolichopterus Tippmann, 1953, preoccupied by Dolichopterus Hall, 1859, Eurypterida. One new synonym is proposed: Championa chemsaki Martins & Napp, 1992 = Championa bifasciata Noguera & Chemsak, 1997.

Sequencing of the genus Arabidopsis identifies a complex history of nonbifurcating speciation and abundant trans-specific polymorphism

Abstract: The notion of species as reproductively isolated units related through a bifurcating tree implies that gene trees should generally agree with the species tree and that sister taxa should not share polymorphisms unless they diverged recently and should be equally closely related to outgroups. It is now possible to evaluate this model systematically. We sequenced multiple individuals from 27 described taxa representing the entire Arabidopsis genus. Cluster analysis identified seven groups, corresponding to described species that capture the structure of the genus. However, at the level of gene trees, only the separation of Arabidopsis thaliana from the remaining species was universally supported, and, overall, the amount of shared polymorphism demonstrated that reproductive isolation was considerably more recent than the estimated divergence times. We uncovered multiple cases of past gene flow that contradict a bifurcating species tree. Finally, we showed that the pattern of divergence differs between gene ontologies, suggesting a role for selection.

The Genus Amblyomma (Ixodidae) in the united States.

Abstract: The publication of a review of the genus Amblyomma in the United States has become desirable because of the increasing interest in the members of this genus as known or suspected carriers of diseases and especially because of the need for criteria for the specific differentiation of the larvae and nymphs. This genus, which is far richer in species than any other, is geographically limited to that portion of the world which is between the 40th parallels of latitude, that is, to the warmer countries. In the United States it is essentially limited to the Southeastern and Southcentral States. C. L. Koch (1844) was the first to publish a comprehensive account of the ticks. He described many new species and the genus Amblyomma. Though he laid the foundation for the systematic classification of ticks, he failed in many instances to select adequate characters. G. Neumann in 1896 began his Revision de la Famille des Ixodes which included Amblyomma and he was the first to use satisfactory morphological characters and thereby made a definite contribution to the classification of genera and species. Donitz (1909) urged the importance of the ornamentation as an aid in recognizing the species and his plan of giving names to the constituent spots and stripes brought order into the terminology of the ornate pattern which most species of Amblyomma display. However, the species of Amblyomma in the United States are readily separated by morphological characters, hence the ornate color patterns are not described in this paper. They are shown in the figures. L. E. Robinson (1926) gives excellent descriptions and figures of the 86 species then known and also summarizes their geographical distribution, hosts, economic aspects, and relation to disease. The more important later writings include Sharif (1928), Dunn (1934), Aragao (1936) and Osorno-Mesa (1941). Other contributions have been made by Warburton (1927), Schulze (1932, 1933, 1936), Kishida (1935) and Cooley and Kohls (1942). The collection of the Rocky Mountain Laboratory now contains 65 described species of Amblyomma from various parts of the world. A study of these and of other available species has led to a fuller understanding of critical morphological and color characters as well as of variation. Variation occurs, particularly in the color patterns, but is less confusing than in some other genera. A single male specimen of Amblyomma ovale (Koch, 1844) taken from a dog, Sept. 8, 1941, Tama Indian Reservation, west of Tama, Iowa, was sent to us for