Dendrolycopodium hickeyi | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Lycophytes |
Class: | Lycopodiopsida |
Order: | Lycopodiales |
Family: | Lycopodiaceae |
Genus: | Dendrolycopodium |
Species: | D. hickeyi |
Binomial name | |
Dendrolycopodium hickeyi | |
Synonyms | |
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Dendrolycopodium hickeyi (synonym Lycopodium hickeyi) known as Hickey's tree club-moss [1] or Pennsylvania clubmoss, [2] is a North American species of clubmoss in the family Lycopodiaceae. It is native to eastern and Central Canada (from Newfoundland to Ontario with isolated populations in Saskatchewan) and the eastern and north-central United States (from Maine west to Minnesota and south as far as Tennessee and North Carolina). [3] The genus Dendrolycopodium is accepted in the Pteridophyte Phylogeny Group classification of 2016 (PPG I), [4] but not in other classifications, which submerge the genus in a larger Lycopodium . [5]
Similar to other members of the genus, the sporophyte of Dendrolycopodium hickeyi resembles the seedlings of some conifers. The upright sporophytes grow from subterranean horizontal stems, often causing tree club-mosses to be found in clusters. [6] [7] The upright sporophytes have small, green microphylls (leaves) extending from the ground to the tips of their branches (branches 4–7mm in diameter). [6] These plants remain green throughout the winter and in their final year, they produce usually a single, unstalked (sessile) terminal strobilus from which spores are released.
Dendrolycopodium hickeyi is ostensibly very similar to D. obscurum which overlaps with D. hickeyi in range. While D. obscurum has reduced leaves on the underside of the branches, D. hickeyi has leaves of equal length around the branches [6] [8] [7] (as reflected by its former name, Lycopodium obscurum var. isophyllum: [9] [10] iso- [“equal”] + -phyllum [“leaf”]). D. hickeyi can be distinguished from D. dendroideum, which also has leaves of equal length around their branches, by the orientation of these leaves. D. hickeyi and D. obscurum both have a single rank of leaves on the top of the branches while D. dendroideum has leaves in ranks of two on the top of each branch. D. hickeyi also has leaves which are appressed to the stem below the first branches (unlike spreading leaves in D. dendroideum [11] ). The strobilus of D. hickeyi is also intermediate in length between D. obscurum and D. dendroideum. [6] [7]
D. hickeyi is native across the northeastern United States and Eastern Canada. [2] [3] [6] It grows in shaded, sandy soil, and can be found in dry or mesic conifer forests. [12] [10] [13] Its range overlaps with several other lycophytes, including D. obscurum and D. dendroideum, which were previously classified as varieties of each other. [2] [3] [10] [11]
The oldest name for the taxon is Lycopodium obscurum var. isophyllum. [9] [10] [14] In elevating the plants from varietal level to species level, Wagner et al. opted to forgo the common (but not mandatory) custom of using the old varietal epithet as the new species epithet since D. hickeyi and D. dendroideum both have leaves of equal length around the branches. They chose instead the name Lycopodium hickeyi in honor of the pteridologist James Hickey who originally described the plant as L. obscurum var. isophyllum. [8]
Lycopodiopsida is a class of vascular plants also known as lycopods or lycophytes. Members of the class are also called clubmosses, firmosses, spikemosses and quillworts. They have dichotomously branching stems bearing simple leaves called microphylls and reproduce by means of spores borne in sporangia on the sides of the stems at the bases of the leaves. Although living species are small, during the Carboniferous, extinct tree-like forms (Lepidodendrales) formed huge forests that dominated the landscape and contributed to coal deposits.
The lycophytes, when broadly circumscribed, are a group of vascular plants that include the clubmosses. They are sometimes placed in a division Lycopodiophyta or Lycophyta or in a subdivision Lycopodiophytina. They are one of the oldest lineages of extant (living) vascular plants; the group contains extinct plants that have been dated from the Silurian. Lycophytes were some of the dominating plant species of the Carboniferous period, and included the tree-like Lepidodendrales, some of which grew over 40 metres (130 ft) in height, although extant lycophytes are relatively small plants.
Huperzia is a genus of lycophyte plants, sometimes known as the firmosses or fir clubmosses; the Flora of North America calls them gemma fir-mosses. This genus was originally included in the related genus Lycopodium, from which it differs in having undifferentiated sporangial leaves, and the sporangia not formed into apical cones. The common name firmoss, used for some of the north temperate species, refers to their superficial resemblance to branches of fir (Abies), a conifer. As of 2020, two very different circumscriptions of the genus were in use. In the Pteridophyte Phylogeny Group classification of 2016, Huperzia is one of three genera in the subfamily Huperzioideae of the family Lycopodiaceae. Most species in the subfamily are placed in the genus Phlegmariurus. Huperzia is left with about 25 species, although not all have been formally transferred to other genera. Other sources recognize only Huperzia, which then has about 340 species.
Lycopodium is a genus of clubmosses, also known as ground pines or creeping cedars, in the family Lycopodiaceae. Two very different circumscriptions of the genus are in use. In the Pteridophyte Phylogeny Group classification of 2016, Lycopodium is one of nine genera in the subfamily Lycopodioideae, and has from nine to 15 species. In other classifications, the genus is equivalent to the whole of the subfamily, since it includes all of the other genera. More than 40 species are accepted.
Lycopodium clavatum is the most widespread species in the genus Lycopodium in the clubmoss family.
Diphasiastrum is a genus of clubmosses in the plant family Lycopodiaceae. In the Pteridophyte Phylogeny Group classification of 2016, it is placed in the subfamily Lycopodioideae. It is closely related to the genus Lycopodium, and some botanists treat it within a broad view of that genus as a section, Lycopodium sect. Complanata. Some species superficially resemble diminutive gymnosperms and have been given common names such as ground-pine or ground-cedar.
Lycopodiella is a genus in the clubmoss family Lycopodiaceae. The genus members are commonly called bog clubmosses, describing their wetland habitat. The genus has a cosmopolitan distribution, with centers of diversity in the tropical New World and New Guinea. In the past, the genus was often incorporated within the related genus Lycopodium, but was segregated in 1964. In the Pteridophyte Phylogeny Group classification of 2016, Lycopodiella is placed in the subfamily Lycopodielloideae, along with three other genera. In this circumscription, the genus has about 15 species. Other sources use a wider circumscription, in which the genus is equivalent to the Lycopodielloideae of PPG I, in which case about 40 species and hybrids are accepted.
Phlegmariurus phlegmaria, synonym Huperzia phlegmaria, commonly known as either coarse tassel fern or common tassel fern, is an epiphytic species native to rainforests in Madagascar, some islands in the Indian Ocean, Asia, Australasia and many Pacific Islands. Phlegmariurus phlegmaria is commonly found in moist forests and rainforests at high altitudes, in and amongst mosses and other epiphytes. Members of the order Lycopodiales are commonly referred to as clubmosses.
Selaginella apoda, commonly known as meadow spikemoss, is a perennial lycophyte native to much of the eastern United States and parts of northeastern Mexico. The life cycle is the shortest of the genus Selaginella, as well as one of the shortest among the lycophytes. Selaginella apoda is found primarily in damp soils in habitats such as swamps, wet fields, open woods and along stream banks. Selaginella apoda presents the potential for case studies involving the plant's adaptability to environmental toxins. It is closely related to Selaginella eclipes and S. ludoviciana, with both of which it has been reported to form hybrids. This group is characterized by relatively flat strobili and large megasporophylls which occur in the same plane as the lateral leaves.
Spinulum annotinum, synonym Lycopodium annotinum, known as interrupted club-moss, or stiff clubmoss, is a species of clubmoss native to forests of the colder parts of North America, as well as Asia, and most of Europe. It is an evergreen perennial pteridophyte. The genus Spinulum is accepted in the Pteridophyte Phylogeny Group classification of 2016, but not in other classifications, which submerge the genus in Lycopodium.
Dendrolycopodium dendroideum, synonym Lycopodium dendroideum, known as tree groundpine, is a North American species of clubmoss. It is part of a complex of species colloquially known as groundpine, which taxa were formerly lumped into the species Lycopodium obscurum. The species is native to Russia and also to the colder parts of North America. The genus Dendrolycopodium is accepted in the Pteridophyte Phylogeny Group classification of 2016, but not in other classifications, which submerge the genus in Lycopodium.
The genus Dendrolycopodium is a clubmoss genus in the family Lycopodiaceae. In the Pteridophyte Phylogeny Group classification of 2016, it is placed in the subfamily Lycopodioideae. Some sources do not recognize the genus, sinking it into Lycopodium. It is treated as section Obscura when retained within Lycopodium. The genus includes a discrete group of plants with similar morphologies. All have erect to semi-erect, branched stems.
Dendrolycopodium obscurum, synonym Lycopodium obscurum, commonly called rare clubmoss, ground pine, or princess pine, is a North American species of clubmoss in the family Lycopodiaceae. It is a close relative of other species such as D. dendroideum and D. hickeyi, also treelike. It is native to the eastern United States and southeastern Canada from Georgia to Minnesota to Nova Scotia. It grows in the understory of temperate coniferous and deciduous forests, where it is involved in seral secondary succession, growing in clonal colonies some years after disturbance has occurred. It has also been found in Japan, Taiwan, Korea, Russian Far East, and northeastern China.
Austrolycopodium magellanicum, synonym Lycopodium magellanicum, the Magellanic clubmoss, is a species of vascular plant in the club moss family Lycopodiaceae. The genus Austrolycopodium is accepted in the Pteridophyte Phylogeny Group classification of 2016, but not in other classifications which submerge the genus in Lycopodium.
Diphasium scariosum, synonym Lycopodium scariosum, commonly known as spreading clubmoss or creeping club moss, is a species in the club moss family Lycopodiaceae. The genus Diphasium is accepted in the Pteridophyte Phylogeny Group classification of 2016, but not in other classifications which submerge the genus in Lycopodium.
Pseudolycopodiella is a genus of non-seed plants in the Lycopodiaceae, long considered part of Lycopodium, but now recognized as a separate genus. It has 10–14 recognized species, only one in North America: Pseudolycopodiella caroliniana.
Pseudolycopodium is a genus of lycophyte in the family Lycopodiaceae with only one species, Pseudolycopodium densum, known as the bushy clubmoss. In the Pteridophyte Phylogeny Group classification of 2016, the genus is placed in the subfamily Lycopodioideae. Some sources do not recognize the genus, sinking it into Lycopodium. Pseudolycopodium densum is native to Australia, the North Island of New Zealand and New Caledonia. It is a spore-bearing vascular plant and grows up to a metre high. It is found in a wide variety of situations, often in high rainfall areas on sandy soils.
Lycopodioideae is a subfamily in the family Lycopodiaceae in the Pteridophyte Phylogeny Group classification of 2016. It is equivalent to a broad circumscription of the genus Lycopodium in other classifications. Like all lycophytes, members of the Lycopodioideae reproduce by spores. The oldest fossils of modern members of the subfamily date to the Early Cretaceous.
Lycopodielloideae is a subfamily in the family Lycopodiaceae in the Pteridophyte Phylogeny Group classification of 2016. 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.