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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).


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Journal Article
01 Jan 1964-Blumea
TL;DR: It is regarded as most likely, that the genus Capparis, as represented in the area under revision, originated in southern India/Ceylon and/or Gondwanaland, and migrated into Australia, and later through the Indo-Chinese Peninsula to the northwest and northeast, and into Malesia.
Abstract: This is a taxonomic revision of the genus Capparis in South and Southeast Asia, Malesia, Australia, and the Pacific. In this area, four sections are distinguished: 1. sect. Capparis, monotypic with C. spinosa, 2. sect. Sodada, monotypic with C. decidua, 3. sect. Monostichocalyx in a new circumscription containing most of the species formerly included in sect. Eucapparis, with about 65 species in the area under revision, 4. sect. Busbeckea, with 12—14 species in all. Of the 79 species recognized, 7 are new, viz. C. cataphyllosa, cinerea, koioides, monantha, pachyphylla, rigida, and rufidula, and 2 are elevated from varietal to specific rank, viz. C. annamensis (C. grandiflora var. annamensis Baker ƒ.) and C. pranensis (C. thorelii var. pranensis Pierre ex Gagn.). Of the 11 subspecies recognized under C. acutifolia, micracantha, and sikkimensis 9 are newly described or new in rank, like 3 out of the 8 varieties under C. loranthifolia, micracantha, and spinosa. Under C. brachybotrya, 2 formae have been maintained, under C. floribunda, is reduced. Three species, C. dielsiana with 2 varieties, C. longipes, and C. muelleriana, have been recorded as incompletely known besides. Chapters on characters and internal relationships, and plant-geographic remarks have been added. All type specimens are cited with the names based on them, the other collections only as far as they are important for the knowledge of the distribution. Notes dealing with deviating specimens, nomenclatural problems, related species in Africa, &c. are given under the taxa. Starting from the idea that solitary large flowers and a beaked ovary with relatively many carpels, the presence of empty spiny bract-like cataphylls at the base of a shoot, and straight thorns are primitive characters, an attempt has been made to devise a subdivision of Sect. Monostichocalyx into 7 tentative Groups to show their natural interrelationships and possible derivation. It is regarded as most likely, that the genus, as represented in the area under revision, originated in southern India/Ceylon and/or Gondwanaland, and migrated into Australia, and later through the Indo-Chinese Peninsula to the northwest and northeast, and into Malesia. An index to numbered collections has been added. Hypselandra Pax & Hoffm. (syn. Meeboldia Pax & Hoffm.) is reduced to Maerua. B.S. Sun’s new taxa from China are discussed in an appendix.

93 citations

Journal Article
TL;DR: The hyphomycetous genus Phialophora is revised and there remain now twelve species or species groups which are redescribed, and the necessary new combinations are proposed.
Abstract: The hyphomycetous genus Phialophora is revised. It is characterized by flask-shaped phialides with a collarette and one-celled slimy conidia. This characterization excludes species which form blastospores on sympodulae besides phialospores, and which have been revised as species of the genus Rhinocladiella in a previous paper. The genus Margarinomyces, on the contrary, is considered to be a synonym of Phialophora. With this emendation there remain now twelve species or species groups which are redescribed. The necessary new combinations are proposed.

93 citations

Journal ArticleDOI
TL;DR: Although rather easily delimited as a family, the Oleaceae contains a great variety of forms, some of which are stable enough to be easily recognized as species, while others, part icular ly in the genus Fraxinus, are a problem for the taxonomist.
Abstract: The Oleaceae are composed of more than 20 genera with over 400 species of temperate and tropical shrubs and trees (Rehder 1940). Many of these, such as Syringa, Forsythia, Jasminum, Ligustru?m, and Fraxinus, are cultivated extensively as ornamentals. Wood of Fraxinus and Olea has a number of commercial uses. The most important member of the family, however, is the olive, which has been grown since antiquity for its fruit and oil. Botanically, the group is particularly interesting as a natural family of plants with a wide geographical distribution, ranging from the tropics through the temperate regions and represented on almost every important land mass in the world except those of the polar regions. Although rather easily delimited as a family, the group contains a great variety of forms, some of which are stable enough to be easily recognized as species, while others, particularly in the genus Fraxinus, are a problem for the taxonomist. Some genetic work has been done in the Oleaceae, where one generic cross is known and several interspecific crosses have been made among the species of Osmanthus, Jasminum, Ligustrum, Forsythia, and especially Syringa, which has produced a multitude of striking forms. Evolutionary trends and phylogenetic relations within the family, as well as its position among related families, offer interesting possibilities for investigation. Although over a thousand species distributed among twenty-four or more genera are listed in Index Kewensis, most taxonomic treatments estimate fewer species, for example, 390-525 species (Johnson 1931), 390 (Engler & Gilg 1924), 370-390 (Knoblauch 1895), 525 (Small 1933), and over 500 (Bailey 1938). These estimates are probably nearer the correct number, since, as is shown in the groups of the family which have been monographed, considerable synonymy occurs (see Gray 1860; Decaisne 1878.; Hill 1910; Wesmael 1892; Lingelseheim 1907, 1920; McKelvey 1928; Steyermark 1932; Knoblauch 1933; Kobuski 1932, 1939a, 1939b, 1940; Rehder 1917; Mansfeld 1924; Gilg 1901; Weber 1928; and Newberry 1937). The first extensive cytological study in the Oleaceae was that of Sax (1930) on the genus Syringa. He found most of the pure species to have either 23 or 24 pairs of chromosomes. From the meiotic behavior of the hybrid S. chinensis (S. persica lacitiata x S. vulgaris), in which he saw about 12 paired and 12 single chromosomes at the first reduction division, he believed the basic number in the genus was probably 12. O'Mara (1930) found 28 chromosomes in all of the species and varieties of Forsythia examined. In the hybrid Forsythia intermedia (P. suspensa x F. viridissima) he found all fourteen chromosomes homologous enough to permit regular pairing and normal behavior at the first and second meiotic divisions, indicating a rather close relationship of the species in this genus. Representative species from several other genera were counted in a study of the chromosomes and anatomy of the secondary xylem of this family by Sax and Abbe (1932). These studies, aside from chromosome numbers of a few species deter-

93 citations

Journal ArticleDOI
24 Jan 2001-Novon
TL;DR: Four new species are described and illustrated: Larnax cuyacensis from Peru, similar to L. sylvarum, but with a rotate, fleshier corolla much lighter in color, and a fruiting calyx tightly appressed to the berry.
Abstract: Based on phylogenies generated using morphological and molecular data, Deprea glabra and D. sylvarum are transferred to Larnax, and a new subspecies, L. sylvarum subsp. novogranatensis, is described. Four new species are described and illustrated: Larnax cuyacensis from Peru, similar to L. glabra and L. sylvarum, but with a rotate, fleshier corolla much lighter in color, and a fruiting calyx tightly appressed to the berry; L. grandiflora from Peru, intermediate between L. andersonii and L. sachapapa; L. parviflora from Peru, similar to L. psilophyta of Ecuador, but differing in vegetative and reproductive characters and having the smallest flowers in the genus; and L. darcyana from Colombia, similar to L. subtriflora of Peru, but differing vegetatively and with much shorter, non-branching hairs, a smaller corolla, shorter filaments, and apiculate anthers. Keys are provided for selected genera and for Larnax. In addition, some synonymies are noted.

93 citations

Journal ArticleDOI
TL;DR: The placement of Leptoporus mollis along with other potential brown-rot species in the phlebioid clade suggests that, in addition to the Antrodia clade,brown-rot fungi may have evolved more than once in Polyporales.

93 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20232,790
20226,199
20212,431
20202,299
20192,015
20182,000