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Chigua (plant)
''Zamia restrepoi'' is a species of cycad in the family Zamiaceae. As of 2020, according to a preliminary field investigations the sole remaining known subpopulation is alarmingly small, comprising fewer than 100 adult specimens. There is a potential for the existence of additional subpopulations, but extensive field surveys have been unsuccessful in locating them, necessitating further research to comprehensively understand the species' population distribution and abundance. Classification history The Type for ''Zamia restrepoi'' was first collected in 1918 by Francis W. Pennell in northern Colombia. The type was not reported again until re-located by Rogrigo Bernal in 1986. Dennis Stevenson described the genus ''Chigua'' and two species, ''C. restrepoi'' and ''C. bernalii'', in 1990. It was recognized that ''Chigua'' was very closely related to ''Zamia'' and might indeed be nested in ''Zamia''. In 2009, Anders Lindström reclassified ''C. restrepoi'' as ''Z. restrepoi'' and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycad
Cycads are seed plants that typically have a stout and woody (ligneous) trunk (botany), trunk with a crown (botany), crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow slowly and have long lifespans. Because of their superficial resemblance to Arecaceae, palms or ferns, they are sometimes mistaken for them, but they are not closely related to either group. Cycads are gymnosperms (naked-seeded), meaning their fertilization, unfertilized seeds are open to the air to be directly fertilized by pollination, as contrasted with angiosperms, which have enclosed seeds with more complex fertilization arrangements. Cycads have very specialized pollinators, usually a specific beetle, and more rarely a thrips or a moth. Both male and female cycads bear cones (strobilus, stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zamiaceae
The Zamiaceae are a family of cycads that are superficially palm or fern-like. They are divided into two subfamilies with eight genera and about 150 species in the tropical and subtropical regions of Africa, Australia and North and South America. The Zamiaceae, sometimes known as zamiads, are perennial, evergreen, and dioecious. They have subterranean to tall and erect, usually unbranched, cylindrical stems, and stems clad with persistent leaf bases (in Australian genera). Their leaves are simply pinnate, spirally arranged, and interspersed with cataphylls. The leaflets are sometimes dichotomously divided. The leaflets occur with several sub-parallel, dichotomously branching longitudinal veins; they lack a mid rib. Stomata occur either on both surfaces or undersurface only. Their roots have small secondary roots. The coralloid roots develop at the base of the stem at or below the soil surface. Male and female sporophylls are spirally aggregated into determinate cones that gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francis W
Francis may refer to: People and characters *Pope Francis, head of the Catholic Church (2013–2025) *Francis (given name), including a list of people and fictional characters * Francis (surname) * Francis, a character played by YouTuber Boogie2988 Places * Rural Municipality of Francis No. 127, Saskatchewan, Canada * Francis, Saskatchewan, Canada ** Francis (electoral district) * Francis, Nebraska, USA * Francis Township, Holt County, Nebraska, USA * Francis, Oklahoma, USA * Francis, Utah, USA Arts, entertainment, media * ''Francis'' (film), the first of a series of comedies featuring Francis the Talking Mule, voiced by Chill Wills *''Francis'', a 1983 play by Julian Mitchell * Francis (band), a Sweden-based folk band *Francis (TV series), a Indian Bengali-language animated television series Other uses * FRANCIS, a bibliographic database * ''Francis'' (1793), a colonial schooner in Australia * Francis turbine, a type of water turbine See also * Saint Francis (disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chigua (plant)
''Zamia restrepoi'' is a species of cycad in the family Zamiaceae. As of 2020, according to a preliminary field investigations the sole remaining known subpopulation is alarmingly small, comprising fewer than 100 adult specimens. There is a potential for the existence of additional subpopulations, but extensive field surveys have been unsuccessful in locating them, necessitating further research to comprehensively understand the species' population distribution and abundance. Classification history The Type for ''Zamia restrepoi'' was first collected in 1918 by Francis W. Pennell in northern Colombia. The type was not reported again until re-located by Rogrigo Bernal in 1986. Dennis Stevenson described the genus ''Chigua'' and two species, ''C. restrepoi'' and ''C. bernalii'', in 1990. It was recognized that ''Chigua'' was very closely related to ''Zamia'' and might indeed be nested in ''Zamia''. In 2009, Anders Lindström reclassified ''C. restrepoi'' as ''Z. restrepoi'' and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petiole (botany)
In botany, the petiole () is the stalk that attaches the leaf blade to the Plant stem, stem. It is able to twist the leaf to face the sun, producing a characteristic foliage arrangement (spacing of blades), and also optimizing its exposure to sunlight. Outgrowths appearing on each side of the petiole in some species are called stipules. The terms wikt:petiolate, petiolate and wikt:apetiolate, apetiolate are applied respectively to leaves with and without petioles. Description The petiole is a stalk that attaches a leaf to the plant stem. In petiolate leaves the leaf stalk may be long (as in the leaves of celery and rhubarb), or short (for example basil). When completely absent, the blade attaches directly to the stem and is said to be Sessility (botany), sessile or apetiolate. Subpetiolate leaves have an extremely short petiole, and may appear sessile. The broomrape family Orobanchaceae is an example of a family in which the leaves are always sessile. In some other plant group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rachis
In biology, a rachis (from the [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the ''rachis'' usually forms the supporting axis of the body and is then called the spine or vertebral column. ''Rachis'' can also mean the central shaft of pennaceous feathers. In the gonad of the invertebrate nematode '' Caenorhabditis elegans'', a rachis is the central cell-free core or axis of the gonadal arm of both adult males and hermaphrodites where the germ cells have achieved pachytene and are attached to the walls of the gonadal tube. The rachis is filled with cytoplasm. In botany In plants, a rachis is the main axis of a compound structure. It can be the main stem of a compound leaf, such as in '' Acacia'' or ferns, or the main, flower-bearing portion of an inflorescence In botany, an inflorescence is a group or cluster of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thorns, Spines, And Prickles
In plant morphology, thorns, spines, and prickles, and in general spinose structures (sometimes called ''spinose teeth'' or ''spinose apical processes''), are hard, rigid extensions or modifications of leaf, leaves, roots, plant stem, stems, or plant bud, buds with sharp, stiff ends, and generally serve the same function: physically plant defense against herbivory, defending plants against herbivory. Description In common language, the terms are used more or less interchangeably, but in botanical terms, thorns are derived from Shoot (botany), shoots (so that they may or may not be branched, they may or may not have leaves, and they may or may not arise from a bud),Simpson, M. G. 2010. "Plant Morphology". In: ''Plant Systematics, 2nd. edition''. Elsevier Academic Press. Chapter 9.Judd, Campbell, Kellogg, Stevens, Donoghue. 2007. "Structural and Biochemical Characters". In: ''Plant Systematics, a phylogenetic approach, third edition''. Chapter 4. spines are derived from Leaf, leaves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaflet (botany)
A leaflet (occasionally called foliole) in botany is a leaf-like part of a compound leaf. Though it resembles an entire leaf, a leaflet is not borne on a main plant stem or branch, as a leaf is, but rather on a leaf, petiole or a branch of the leaf. Compound leaves are common in many plant families and they differ widely in morphology (biology), morphology. The two main classes of compound leaf morphology are Leaf shape, palmate and pinnate. For example, a ''Cannabis, hemp'' plant has palmate compound leaves, whereas some species of ''Acacia sensu lato, Acacia'' have pinnate leaves. The ultimate free division (or leaflet) of a compound leaf, or a pinnate subdivision of a multipinnate leaf is called a pinnule or pinnula. Image:Ветвь акации.jpg, Pinnate leaf of a Fabaceae, legume with 10 leaflets Image:Mimosa Pudica.gif, ''Mimosa pudica'' folding leaflets inward. See also * Compound leaf References Leaf morphology {{plant-morphology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rain Forest
Rainforests are forests characterized by a closed and continuous tree Canopy (biology), canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforests can be generally classified as tropical rainforests or temperate rainforests, but other types have been described. Estimates vary from 40% to 75% of all biotic community, biotic species being Indigenous (ecology), indigenous to the rainforests. There may be many millions of species of plants, insects and microorganisms still undiscovered in tropical rainforests. Tropical rainforests have been called the "jewels of the Earth" and the "medicine chest (idiom), world's largest pharmacy", because over one quarter of natural medicines have been discovered there. Rainforests as well as endemic rainforest species are rapidly disappearing due to #Deforestation, deforestation, the resulting habitat loss and air pollution, pollution of the atmosphere. Definition Rainforests are cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
