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21-728: Lushan Botanical Garden is famous for its gymnosperm collection, which had been introduced from 15 countries. There are more than 200 species of Gymnosperms from 11 families and 41 genera within its Pinales special park. Lushan Botanical Garden is a member of Botanic Gardens Conservation International (BGCI) and the Initiative for Collective Conservation in Chinese Botanical Gardens (ICCBG). The botanical garden currently hosts 140 staff, including 43 doctors and 40 master’s degree holders , being mainly from Nanchang University . The garden hosts 800,000 tourists annually. Within

42-698: A polyphyletic grouping of extinct seed-producing plants . The earliest fossil evidence for plants of this type are the lyginopterids of late Devonian age. They flourished particularly during the Carboniferous and Permian periods. Pteridosperms declined during the Mesozoic Era and had mostly disappeared by the end of the Cretaceous Period, though Komlopteris seem to have survived into Eocene times, based on fossil finds in Tasmania . With regard to

63-543: A group of seed-producing plants that include conifers , cycads , Ginkgo , and gnetophytes , forming the clade Gymnospermae . The term gymnosperm comes from the composite word in Greek : γυμνόσπερμος ( γυμνός , gymnos , 'naked' and σπέρμα , sperma , 'seed'), and literally means 'naked seeds'. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with

84-408: A now-extinct family with members which (in an example of convergent evolution ) resembled the modern butterflies that arose far later. All gymnosperms are perennial woody plants , Unlike in other extant gymnosperms the soft and highly parenchymatous wood in cycads is poorly lignified, and their main structural support comes from an armor of sclerenchymatous leaf bases covering the stem, with

105-432: A purely curatorial perspective the term pteridosperms is a useful shorthand for describing the fern-like fronds that were probably produced by seed plants, which are commonly found in many Palaeozoic and Mesozoic fossil floras. The concept of pteridosperms goes back to the late 19th century when palaeobotanists came to realise that many Carboniferous fossils resembling fern fronds had anatomical features more reminiscent of

126-435: Is dependent on the sporophytic phase. The term "gymnosperm" is often used in paleobotany to refer to (the paraphyletic group of) all non-angiosperm seed plants. In that case, to specify the modern monophyletic group of gymnosperms, the term Acrogymnospermae is sometimes used. The gymnosperms and angiosperms together constitute the spermatophytes or seed plants. The spermatophytes are subdivided into five divisions ,

147-531: The Petriellales , Corystospermales and Caytoniales . Their discovery attracted considerable attention at the time, as the pteridosperms were the first extinct group of vascular plants to be identified solely from the fossil record. In the 19th century the Carboniferous Period was often referred to as the "Age of Ferns" but these discoveries during the first decade of the 20th century made it clear that

168-518: The "Age of Pteridosperms" was perhaps a better description. During the 20th century the concept of pteridosperms was expanded to include various Mesozoic groups of seed plants with fern-like fronds, such as the Corystospermaceae . Some palaeobotanists also included seed plant groups with entire leaves such as the Glossopteridales and Gigantopteridales , which was stretching the concept. In

189-736: The Botanical Garden also resides the locations for the tomb of Chen Yinke and the " Three Founders tomb  [ zh ] " (Hu Hsen-Hsu, Ren-Chang Ching, and Chen Fenghuai), both of which are protected cultural relics. This article about a building or structure in China is a stub . You can help Misplaced Pages by expanding it . This garden-related article is a stub . You can help Misplaced Pages by expanding it . Gymnosperm The gymnosperms ( / ˈ dʒ ɪ m n ə ˌ s p ɜːr m z , - n oʊ -/ JIM -nə-spurmz, -⁠noh- ; lit.   ' revealed seeds ' ) are

210-522: The angiosperms and four divisions of gymnosperms: the Cycadophyta , Ginkgophyta , Gnetophyta , and Pinophyta (also known as Coniferophyta). Newer classification place the gnetophytes among the conifers. Numerous extinct seed plant groups are recognised including those considered pteridosperms/seed ferns , as well other groups like the Bennettitales. By far the largest group of living gymnosperms are

231-520: The conifers (pines, cypresses, and relatives), followed by cycads, gnetophytes ( Gnetum , Ephedra and Welwitschia ), and Ginkgo biloba (a single living species). About 65% of gymnosperms are dioecious , but conifers are almost all monoecious . Some genera have mycorrhiza , fungal associations with roots ( Pinus ), while in some others ( Cycas ) small specialised roots called coralloid roots are associated with nitrogen-fixing cyanobacteria . Over 1,000 living species of gymnosperm exist. It

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252-539: The context of modern phylogenetic models, the groups often referred to as pteridosperms appear to be liberally spread across a range of clades, and many palaeobotanists today would regard pteridosperms as little more than a paraphyletic 'grade-group' with no common lineage. One of the few characters that may unify the group is that the ovules were borne in a cupule , a group of enclosing branches, but this has not been confirmed for all "pteridosperm" groups. It has been speculated that some seed fern groups may be close to

273-493: The critical discovery that some of these fronds (genus Lyginopteris ) were associated with seeds (genus Lagenostoma ) that had identical and very distinctive glandular hairs, and concluded that both fronds and seeds belonged to the same plant. Soon, additional evidence came to light suggesting that seeds were also attached to the Carboniferous fern-like fronds Dicksonites , Neuropteris and Aneimites . Initially it

294-511: The enduring utility of this division , many palaeobotanists still use the pteridosperm grouping in an informal sense to refer to the seed plants that are not angiosperms , coniferoids ( conifers or cordaites ), ginkgophytes or cycadophytes (cycads or bennettites ). This is particularly useful for extinct seed plant groups whose systematic relationships remain speculative, as they can be classified as pteridosperms with no valid implications being made as to their systematic affinities. Also, from

315-900: The exception of species with underground stems. There are no herbaceous gymnosperms and compared to angiosperms they occupy fewer ecological niches , but have evolved both parasites ( Parasitaxus ), epiphytes ( Zamia pseudoparasitica ) and rheophytes ( Retrophyllum minus ). Conifers are by far the most abundant extant group of gymnosperms with six to eight families, with a total of 65–70 genera and 600–630 species (696 accepted names). Most conifers are evergreens . The leaves of many conifers are long, thin and needle-like, while other species, including most Cupressaceae and some Podocarpaceae , have flat, triangular scale-like leaves. Agathis in Araucariaceae and Nageia in Podocarpaceae have broad, flat strap-shaped leaves. Cycads are

336-550: The late Devonian period around 383 million years ago. It has been suggested that during the mid-Mesozoic era, pollination of some extinct groups of gymnosperms was by extinct species of scorpionflies that had specialized proboscis for feeding on pollination drops. The scorpionflies likely engaged in pollination mutualisms with gymnosperms, long before the similar and independent coevolution of nectar-feeding insects on angiosperms. Evidence has also been found that mid-Mesozoic gymnosperms were pollinated by Kalligrammatid lacewings ,

357-525: The modern-day seed plants, the cycads . In 1899 the German palaeobotanist Henry Potonié coined the term " Cycadofilices " ("cycad-ferns") for such fossils, suggesting that they were a group of non-seed plants intermediate between the ferns and cycads. Shortly afterwards, the British palaeobotanists Frank Oliver and Dukinfield Henry Scott (with the assistance of Oliver's student at the time, Marie Stopes ) made

378-1158: The next most abundant group of gymnosperms, with two or three families, 11 genera, and approximately 338 species. A majority of cycads are native to tropical climates and are most abundantly found in regions near the equator. The other extant groups are the 95–100 species of Gnetales and one species of Ginkgo . Today, gymnosperms are the most threatened of all plant groups. Ginkgo Cycas Dioon Bowenia Macrozamia Encephalartos Lepidozamia Ceratozamia Stangeria Microcycas Zamia Ephedra Gnetum Welwitschia Larix Pseudotsuga Pinus Cathaya Picea Cedrus Abies Keteleeria Pseudolarix Nothotsuga Tsuga Araucaria Agathis Wollemia Halocarpus Pectinopitys Prumnopitys Sundacarpus Lepidothamnus Phyllocladus Parasitaxus Lagarostrobos Manoao Saxegothaea Microcachrys Pherosphaera Pteridospermatophyta Pteridospermatopsida Pteridospermatophyta , also called " pteridosperms " or " seed ferns " are

399-433: The seeds and ovules of flowering plants ( angiosperms ), which are enclosed within an ovary . Gymnosperm seeds develop either on the surface of scales or leaves , which are often modified to form cones , or on their own as in yew , Torreya , and Ginkgo . The life cycle of a gymnosperm involves alternation of generations , with a dominant diploid sporophyte phase, and a reduced haploid gametophyte phase, which

420-662: Was previously widely accepted that the gymnosperms originated in the Late Carboniferous period, replacing the lycopsid rainforests of the tropical region, but more recent phylogenetic evidence indicates that they diverged from the ancestors of angiosperms during the Early Carboniferous . The radiation of gymnosperms during the late Carboniferous appears to have resulted from a whole genome duplication event around 319  million years ago . Early characteristics of seed plants are evident in fossil progymnosperms of

441-618: Was still thought that they were " transitional fossils " intermediate between the ferns and cycads, and especially in the English-speaking world they were referred to as "seed ferns" or "pteridosperms". Today, despite being regarded by most palaeobotanists as only distantly related to ferns, these spurious names have nonetheless established themselves. Nowadays, four orders of Palaeozoic seed plants tend to be referred to as pteridosperms: Lyginopteridales , Medullosales , Callistophytales and Peltaspermales , with "Mesozoic seed ferns" including

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