Per Karl Hjalmar Dusén
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Per Karl Hjalmar Dusén
Per Karl Hjalmar Dusén (1855–1926) was a Swedish civil engineer, botanist and explorer. As a botanist his interests included pteridology, bryology, and paleobotany. He made botanical expeditions to Africa, Greenland, and South America. During his expeditions to Greenland, he visited Disko Island to catalogue the variety of flowering plants, horsetails and ferns. Between 1890 and 1892, Dusén collected nearly 560 leaf fossils preserved in basalt in the vicinity of Mount Cameroon on the west coast of Cameroon. Later, these fossils were studied by the German paleobotanist Paul J. Menzel (1864–1927). His botanical specimens are at the New York Botanical Garden, being obtained when they acquired the herbarium of Princeton University in 1945. Honours More than 200 species were named in his honour, including: * (Acanthaceae) '' Acanthus dusenii'' C.B.Clarke * (Acanthaceae) '' Justicia dusenii'' (Lindau) Wassh. & L.B.Sm. in Reitz * (Anacardiaceae) '' Trichoscypha dusenii'' Engl. * ...
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Botany
Botany, also called plant science (or plant sciences), plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek word (') meaning " pasture", "herbs" " grass", or "fodder"; is in turn derived from (), "to feed" or "to graze". Traditionally, botany has also included the study of fungi and algae by mycologists and phycologists respectively, with the study of these three groups of organisms remaining within the sphere of interest of the International Botanical Congress. Nowadays, botanists (in the strict sense) study approximately 410,000 species of land plants of which some 391,000 species are vascular plants (including approximately 369,000 species of flowering plants), and approximately 20,000 are bryophytes. Botany originated in prehistory as herbalism with the efforts of early humans to identify – a ...
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Acanthaceae
Acanthaceae is a family (the acanthus family) of dicotyledonous flowering plants containing almost 250 genera and about 2500 species. Most are tropical herbs, shrubs, or twining vines; some are epiphytes. Only a few species are distributed in temperate regions. The four main centres of distribution are Indonesia and Malaysia, Africa, Brazil, and Central America. Representatives of the family can be found in nearly every habitat, including dense or open forests, scrublands, wet fields and valleys, sea coast and marine areas, swamps, and mangrove forests. Description Plants in this family have simple, opposite, decussated leaves with entire (or sometimes toothed, lobed, or spiny) margins, and without stipules. The leaves may contain cystoliths, calcium carbonate concretions, seen as streaks on the surface. The flowers are perfect, zygomorphic to nearly actinomorphic, and arranged in an inflorescence that is either a spike, raceme, or cyme. Typically, a colorful brac ...
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Teiidae
Teiidae is a family of autarchoglossan lizards native to the Americas. Members of this family are generally known as whiptails or racerunners; however, tegus also belong to this family. Teiidae is sister to the Gymnopthalmidae, and both families comprise the Teiioidea. The Teiidae includes several parthenogenic species – a mode of clonal reproduction. Presently, the Teiidae consists of approximately 150 species in eighteen genera. Morphology and behavior Teiids can be distinguished from other lizards by the following characteristics: they have large rectangular scales that form distinct transverse rows ventrally and generally small granular scales dorsally, they have head scales that are separate from the skull bones, and the teiid teeth are solid at the base and "glued" to the jaw bones. Additionally, all teiids have a forked, snake-like tongue. They all possess well-developed limbs. Teiids are all terrestrial (few are semi-aquatic) and diurnal, and are primarily carnivor ...
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Asplenium Dusenii
''Asplenium'' is a genus of about 700 species of ferns, often treated as the only genus in the family (biology), family Aspleniaceae, though other authors consider ''Hymenasplenium'' separate, based on molecular phylogenetic analysis of DNA sequences, a different chromosome count, and structural differences in the rhizomes. The type species for the genus is ''Asplenium marinum''. The most common vernacular name is spleenworts, applied to the more "typical" species. ''Asplenium nidus, A. nidus'' and several similar species are called bird's-nest ferns, the ''Camptosorus'' group is known as walking ferns, and distinct names are applied to some other particularly well-known species. Taxonomy and genetics Many groups of species have been separated from ''Asplenium'' as Segregate (taxonomy), segregate genera. These include ''Camptosorus'', ''Ceterach'', ''Phyllitis'', and ''Tarachia'', but these species can form hybrid (biology), hybrids with other ''Asplenium'' species and because of ...
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Aspleniaceae
The Aspleniaceae (spleenworts) are a family of ferns, included in the order Polypodiales. The composition and classification of the family have been subject to considerable changes. In particular, there is a narrow circumscription, Aspleniaceae s.s. (adopted here), in which the family contains only two genera, and a very broad one, Aspleniaceae s.l., in which the family includes 10 other families kept separate in the narrow circumscription, with the Aspleniaceae s.s. being reduced to the subfamily Asplenioideae. The family has a worldwide distribution, with many species in both temperate and tropical areas. Elongated unpaired sori are an important characteristic of most members of the family. Description Members of the family grow from rhizomes, that are either creeping or somewhat erect, and are usually but not always unbranched, and have scales that usually have a lattice-like (clathrate) structure. In some species, for example ''Asplenium nidus'', the rhizomes form a kind o ...
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Trachymene Dusenii
file:Australian Lace Flower.jpg, ''Trachymene coerulea'' (Australian lace flower) ''Trachymene'' is a genus of herbaceous plants in the family Araliaceae. The species are native to Australia, Malesia, New Caledonia and Fiji. Species include: *''Trachymene anisocarpa'' (Turcz.) *''Trachymene bialata'' (Domin) B.L.Burtt *''Trachymene bivestita'' (Domin) L.A.S.Johnson *''Trachymene ceratocarpa'' (W. Fitzg.) Keighery & Rye *''Trachymene clivicola'' Boyland & A.E.Holland *''Trachymene coerulea'' Graham - Blue lace flower *''Trachymene composita'' (Domin) B.L.Burtt *''Trachymene croniniana'' (F.Muell.) T.Durand & B.D.Jacks. *''Trachymene cussonii'' (Montrouz.) B.L.Burtt *''Trachymene cyanantha'' Boyland *''Trachymene cyanopetala'' (F.Muell.) Benth. - Purple parsnip *''Trachymene dendrothrix'' Maconochie *''Trachymene didiscoides'' (F.Muell.) B.L.Burtt *''Trachymene dusenii'' (Domin) F.M.Bailey *''Trachymene elachocarpa'' (F.Muell.) B.L.Burtt *''Trachymene g ...
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