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Lycopodielloideae

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26-731: See text Lycopodiella Holub sensu Øllgaard (1987) Lycopodielloideae is a subfamily in the family Lycopodiaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). It is equivalent to a broad circumscription of the genus Lycopodiella in other classifications. Like all lycophytes , members of the Lycopodielloideae are vascular plants that reproduce by spores. The sporophytes of Lycopodielloideae species are relatively short herbaceous plants. They have stems with pseudomonopodial branching in which unequal binary branching produces

52-497: A colorless lower part in contact with fungal hyphae. In Lycopodioideae monoplastidic meiosis is common, whereas polyplastidic meiosis is found in Lycopodielloideae and Huperzioideae. The family Lycopodiaceae is considered to be basal within the Lycopodiopsida (lycophytes). One hypothesis for the evolutionary relationships involved is shown in the cladogram below. Lycopodiaceae Isoetaceae Selaginellaceae Within

78-418: A single genus Lycopodiella sensu lato in other systems of classification. Lycopodiaceae See text The Lycopodiaceae (class Lycopodiopsida , order Lycopodiales) are an old family of vascular plants , including all of the core clubmosses and firmosses , comprising 16 accepted genera and about 400 known species. This family originated about 380 million years ago in the early Devonian, though

104-406: Is known as the gne-pine hypothesis and looks like: (flowering plants) [REDACTED] Cycads [REDACTED] Ginkgo [REDACTED] Pinaceae (the pine family) [REDACTED] Gnetophytes [REDACTED] other conifers [REDACTED] However, the relationships between these groups should not be considered settled. Other classifications group all the seed plants in

130-480: Is suspected that the extension was involved in anemophilous (wind) pollination . Runcaria sheds new light on the sequence of character acquisition leading to the seed. Runcaria has all of the qualities of seed plants except for a solid seed coat and a system to guide the pollen to the seed. Runcaria was followed shortly after by plants with a more condensed cupule, such as Spermasporites and Moresnetia . Seed-bearing plants had diversified substantially by

156-480: The International Code of Botanical Nomenclature as it was then. The names were validated by Benjamin Øllgaard in 2015. The entire subfamily Lycopodielloideae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I) corresponds to the single genus Lycopodiella in other classifications. Within the family Lycopodiaceae, there is support for three subgroups. In 2016, Field et al. proposed that

182-572: The Famennian , the last stage of the Devonian. Examples include Elkinsia , Xenotheca , Archaeosperma , " Hydrasperma ", Aglosperma , and Warsteinia . Some of these Devonian seeds are now classified within the order Lyginopteridales . Seed-bearing plants are a clade within the vascular plants (tracheophytes). The spermatophytes were traditionally divided into angiosperms , or flowering plants, and gymnosperms , which includes

208-514: The Triassic period, seed ferns had declined in ecological importance, and representatives of modern gymnosperm groups were abundant and dominant through the end of the Cretaceous , when the angiosperms radiated. A whole genome duplication event in the ancestor of seed plants occurred about 319  million years ago . This gave rise to a series of evolutionary changes that resulted in

234-526: The Early Cretaceous of China. Spermatophyte A seed plant or spermatophyte ( lit.   ' seed plant ' ; from Ancient Greek σπέρματος ( spérmatos )  'seed' and φυτόν (phytón)  'plant'), also known as a phanerogam (taxon Phanerogamae ) or a phaenogam (taxon Phaenogamae ), is any plant that produces seeds . It is a category of embryophyte (i.e. land plant) that includes most of

260-448: The PPG I system, the family has 16 accepted genera, grouped into three subfamilies, Lycopodielloideae, Lycopodioideae and Huperzioideae, based in part on molecular phylogenetic studies. The Huperzioideae differ in producing spores in small lateral structures in the leaf axils, and it has been suggested that they be recognized as a separate family. Other sources use fewer genera; for example,

286-1418: The World recognized the following genera as members of Lycopodiaceae. All of these are recognized by the Pteridophyte Phylogeny Group classification of 2016 (PPG I), except for the genus Brownseya , described in 2021. Other classifications circumscribe the genera in the family more broadly, recognizing the subfamilies Lycopodielloideae, Lycopodioideae, and Huperzioideae as the genera Lycopodiella , Lycopodium , and Huperzia . Phylogeny of Lycopodiaceae Huperzia s.s. Bernhardi Phylloglossum Kunze Phlegmariurus (Herter) Holub Brownseya Zhang et al. Palhinhaea Franco & Vasconcellos Lateristachys Holub Pseudolycopodiella Holub Lycopodiella Holub Lycopodiastrum Holub ex Dixit Diphasiastrum Holub Lycopodium s.s. von Linné Spinulum Haines Pseudolycopodium Preslia ex Holub Pseudodiphasium Holub Austrolycopodium Holub Dendrolycopodium Haines Diphasium Presl ex Rothmaler The members of Lycopodiaceae are terrestrial or epiphytic in habit and are most prevalent in tropical mountain and alpine environments. Though Lycopodiaceae are most abundant in these regions, they are cosmopolitan, excluding arid environments. Lycopodiaceae (homosporous lycophytes) split off from

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312-528: The appearance of a main stem with secondary side branches. The main stems are indeterminate and of various forms, including rhizomatous , creeping and upright. The branches are usually determinate (i.e. of limited growth and extension). Sporangia are borne at the bases or in the axils of special spore-bearing leaves ( sporophylls ), which are notably different from the normal leaves, and are grouped into compact terminal structures ( strobili ). The strobili may be either upright or drooping. The family Lycopodiaceae

338-427: The branch leading to Selaginella and Isoetes (heterosporous lycophytes) about ~400 million years ago, during the early Devonian. The two subfamilies Lycopodioideae and Huperzioideae diverged ~350 million years ago, but has evolved so slowly that about 30% of their genes are still in syntenic blocks (remaining in the same arrangement). They have also gone through independent whole genome duplications . In most plants

364-428: The diversity within the family has been much more recent. "Wolf foot" is another common name for this family due to the resemblance of either the roots or branch tips to a wolf's paw. Members of Lycopodiaceae are not spermatophytes and so do not produce seeds . Instead they produce spores , which are oily and flammable, and are the most economically important aspects of these plants. The spores are of one size (i.e.

390-659: The familiar land plants, including the flowering plants and the gymnosperms , but not ferns , mosses , or algae . The term phanerogam or phanerogamae is derived from the Greek φανερός ( phanerós ), meaning "visible", in contrast to the term "cryptogam" or " cryptogamae " (from Ancient Greek κρυπτός (kruptós)  'hidden'), together with the suffix γαμέω ( gaméō ), meaning "to marry". These terms distinguish those plants with hidden sexual organs (cryptogamae) from those with visible ones (phanerogamae). The extant spermatophytes form five divisions,

416-690: The family, there is support for three subgroups. In 2016, Field et al. proposed that the primary division is between Lycopodielloideae plus Lycopodioideae and the Huperzioideae (names sensu PPG I). Lycopodielloideae ( Lycopodiella s.l.) Lycopodioideae ( Lycopodium s.l.) Huperzioideae ( Huperzia s.l.) There are about 400 known species in the family Lycopodiaceae. Sources differ in how they group these into genera. Field et al. (2016) say "Most Lycopodiaceae species have been re-classified into different genera several times, leading to uncertainty about their most appropriate generic identification." In

442-401: The first four of which are classified as gymnosperms , plants that have unenclosed, "naked seeds": The fifth extant division is the flowering plants , also known as angiosperms or magnoliophytes, the largest and most diverse group of spermatophytes: In addition to the five living taxa listed above, the fossil record contains evidence of many extinct taxa of seed plants, among those: By

468-482: The genera shown in the following cladogram, where the number of species included in the study is shown in parentheses: Lycopodiella (2 spp.) Pseudolycopodiella (1 sp.) Lateristachys (1 sp.) Palhinhaea (4 spp.) In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the Lycopodielloideae comprises the following genera: All of these genera are submerged into

494-431: The gnetophytes, cycads, ginkgo, and conifers. Older morphological studies believed in a close relationship between the gnetophytes and the angiosperms, in particular based on vessel elements . However, molecular studies (and some more recent morphological and fossil papers) have generally shown a clade of gymnosperms , with the gnetophytes in or near the conifers. For example, one common proposed set of relationships

520-510: The majority of duplicate genes are lost relatively quickly through diploidization , but in this group both sets of genes tends to be retained with relatively few alterations, even after hundreds of millions of years after the duplication event. Spores indicate that the crown group of Lycopodiaceae had emerged by the Triassic-Jurassic boundary, around 200 million years ago, with a member of the crown group of Lycopodioideae known from

546-452: The microphylls often densely cover the stem in a linear, scale-like, or appressed fashion to the stem, and the leaves are either opposite or spirally arranged. The club mosses commonly grow to be 5–20 cm tall. The gametophytes in most species are non-photosynthetic and myco-heterotrophic , but the subfamily Lycopodielloideae and a few species in the subfamily Huperzioideae have gametophytes with an upper green and photosynthetic part, and

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572-413: The origin of modern seed plants. A middle Devonian (385-million-year-old) precursor to seed plants from Belgium has been identified predating the earliest seed plants by about 20 million years. Runcaria , small and radially symmetrical, is an integumented megasporangium surrounded by a cupule. The megasporangium bears an unopened distal extension protruding above the mutlilobed integument . It

598-408: The plants are isosporous ) and are borne on a specialized structure at the apex of a shoot called a strobilus (plural: strobili), which resembles a tiny battle club , from which the common name derives. Members of the family share the common feature of having a microphyll , which is a "small leaf with a single vein, and not associated with a leaf gap in the central vascular system." In Lycopodiaceae,

624-407: The primary division is between Lycopodielloideae plus Lycopodioideae (which comprised their Lycopodioideae) and Huperzioideae (subfamilies sensu PPG I). Lycopodielloideae ( Lycopodiella s.l.)  Lycopodioideae ( Lycopodium s.l.)  Huperzioideae ( Huperzia s.l.) Field et al. (2016) included eight species of Lycopodielloideae in their analysis, which suggested the relationships among

650-534: The three genera placed in the subfamily Huperzioideae in PPG I, Huperzia , Phlegmariurus and Phylloglossum , have also all been treated within a broadly defined Huperzia . The species within this family generally have chromosome counts of n =34. A notable exception are the species in Diphasiastrum , which have counts of n =23. As of June 2024 , the Checklist of Ferns and Lycophytes of

676-775: Was first established in 1802. Although other genera now placed within the family (in particular Huperzia , published in 1801) had been described, until the mid-1900s, Lycopodium was often the only genus recognized. Work by Josef Holub and Benjamin Øllgaard in the 1980s established three clear divisions within the family. This has since been supported by molecular phylogenetic studies. Several different ways of representing this situation taxonomically have been used, and are still in use as of 2019, including three subfamilies with multiple genera, and three genera with multiple subgeneric divisions. Three subfamilies, including Lycopodielloideae, were first suggested by Warren Wagner Jr. and Joseph Beitel in 1992, but were not validly published under

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