Podomitrium phyllanthus | |
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Podomitrium phyllanthus. Note the undulating margins | |
Scientific classification | |
Kingdom: | Plantae |
Division: | Marchantiophyta |
Class: | Jungermanniopsida |
Order: | Pallaviciniales |
Family: | Pallaviciniaceae |
Genus: | Podomitrium |
Species: | P. phyllanthus |
Binomial name | |
Podomitrium phyllanthus | |
Podomitrium phyllanthus has a sparse distribution in Australia, New Zealand and New Caledonia. [1] |
Podomitrium phyllanthus is a thalloid liverwort in the family Pallaviciniaceae. It is found in wet forests and rainforests of Australia, New Zealand and New Caledonia.
Podomitrium phyllanthus is a thalloid, unbranched liverwort with undulate margins. The thallus is up to 70mm long and 7mm wide, and tapers at the base to form a spathulate shape. The thallus is bright green in colour with a single vein down each thallus. Single-celled rhizoids grow from the base of the thallus to keep the liverwort attached to the substrate.
When reproducing sexually, P. phyllanthus individuals grow a white seta (stalk) from the base of the thallus upon which bears a single black capsule holding millions of tiny spores for reproduction. When reproducing asexually, the upper surface of the thallus holds gemma cups. The species can often be confused with Symphyogyna or Pallavicinia ; [2] the difference is that P. phyllanthus does not branch as often as Symphyogna and has undulate margins without teeth.
Sexual (gametophyte) and asexual (sporophyte) generations characterise liverwort life cycles; the thallus is haploid and the dominant generation and develops from a germinating spore. [3] Sperm from the male reproductive organ (antheridium) travel through an aqueous environment to fertilise the eggs held in the female reproductive organ (archegonium); consequently the species are dependent on moist environments. The sporophyte generation develops from this diploid embryo and forms a sporangium at its apex; the capsule. Spores are released when the sporangium is ruptured, which marks the start of the next gametophyte generation. [3] Liverworts can also reproduce asexually via gemma cups, which disperse clones of the parent via water droplets.
Podomitrium phyllanthus is distributed sparsely around Australia, especially in Tasmania and the east coast of Australia; New Zealand, on both the North and South Island, the Auckland Islands and Raoul Island; and New Caledonia. [1] Its distribution aligns with the presence of wet forest and rainforest in which it resides. The species' distribution is also a product of its relatively low dispersion capability. P. phyllanthus grows on moist soil, damp rocks or fallen trees. [3] The species has a patchy distribution within forests.
The plants are not directly economically important to humans but are an important part of the ecosystem as nutrition for animals and by facilitating decay and aiding disintegration of rocks through their ability to retain moisture. [3] Therefore, P. phyllanthus has an indirect economic importance to humans, since functioning ecosystems provide humans with ecosystem services such as carbon sequestration and clean water supplies. [4]
IUCN categorises the species globally as viable i.e. of least concern; [5] this means the species does not face major threats in the near future and thus is not included on the red list. Like many species, however, it faces threats from deforestation and changing conditions with climate change. [6]
Alternation of generations is the predominant type of life cycle in plants and algae. In plants both phases are multicellular: the haploid sexual phase – the gametophyte – alternates with a diploid asexual phase – the sporophyte.
Bryophytes are a group of land plants, sometimes treated as a taxonomic division, that contains three groups of non-vascular land plants (embryophytes): the liverworts, hornworts and mosses. In the strict sense, Bryophyta consists of the mosses only. Bryophytes are characteristically limited in size and prefer moist habitats although they can survive in drier environments. The bryophytes consist of about 20,000 plant species. Bryophytes produce enclosed reproductive structures, but they do not produce flowers or seeds. They reproduce sexually by spores and asexually by fragmentation or the production of gemmae. Though bryophytes were considered a paraphyletic group in recent years, almost all of the most recent phylogenetic evidence supports the monophyly of this group, as originally classified by Wilhelm Schimper in 1879. The term bryophyte comes from Ancient Greek βρύον (brúon) 'tree moss, liverwort', and φυτόν (phutón) 'plant'.
The Marchantiophyta are a division of non-vascular land plants commonly referred to as hepatics or liverworts. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information.
A sporophyte is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase.
Hornworts are a group of non-vascular Embryophytes constituting the division Anthocerotophyta. The common name refers to the elongated horn-like structure, which is the sporophyte. As in mosses and liverworts, hornworts have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information; the flattened, green plant body of a hornwort is the gametophyte stage of the plant.
Non-vascular plants are plants without a vascular system consisting of xylem and phloem. Instead, they may possess simpler tissues that have specialized functions for the internal transport of water.
Marchantia is a genus of liverworts in the family Marchantiaceae and the order Marchantiales.
Lunularia cruciata, the crescent-cup liverwort, is a liverwort of the order Marchantiales, and the only species in the genus Lunularia and family Lunulariaceae. The name, from Latin luna, moon, refers to the moon-shaped gemma cups.
Conocephalum is a genus of complex thalloid liverworts in the order Marchantiales and is the only extant genus in the family Conocephalaceae. Some species of Conocephalum are assigned to the Conocephalum conicum complex, which includes several cryptic species. Conocephalum species are large liverworts with distinct patterns on the upper thallus, giving the appearance of snakeskin. The species Conocephalum conicum is named for its cone-shaped reproductive structures, called archegoniophores. Common names include snakeskin liverwort, great scented liverwort and cat-tongue liverwort.
Monoicy is a sexual system in haploid plants where both sperm and eggs are produced on the same gametophyte, in contrast with dioicy, where each gametophyte produces only sperm or eggs but never both. Both monoicous and dioicous gametophytes produce gametes in gametangia by mitosis rather than meiosis, so that sperm and eggs are genetically identical with their parent gametophyte.
A prothallus, or prothallium, is usually the gametophyte stage in the life of a fern or other pteridophyte. Occasionally the term is also used to describe the young gametophyte of a liverwort or peat moss as well. In lichens it refers to the region of the thallus that is free of algae.
Plant reproduction is the production of new offspring in plants, which can be accomplished by sexual or asexual reproduction. Sexual reproduction produces offspring by the fusion of gametes, resulting in offspring genetically different from either parent. Asexual reproduction produces new individuals without the fusion of gametes, resulting in clonal plants that are genetically identical to the parent plant and each other, unless mutations occur.
Cavicularia densa is the only species in the liverwort genus Cavicularia. The species was first described in 1897 by Franz Stephani, and is endemic to Japan, where it grows on fine moist soil.
Marchantia polymorpha is a species of large thalloid liverwort in the class Marchantiopsida. M. polymorpha is highly variable in appearance and contains several subspecies. This species is dioicous, having separate male and female plants. M. polymorpha has a wide distribution and is found worldwide. Common names include common liverwort or umbrella liverwort.
Marchantia berteroana is a liverwort species in the genus Marchantia.
Hypnodendron comosum, commonly known as palm moss or palm tree moss, is a ground moss which can be divided into two varieties: Hypnodendron comosum var. comosum and Hypnodendron comosum var. sieberi. Both Hypnodendron varieties most commonly grow in damp locations in the temperate and tropical rainforests of New South Wales, Victoria, and Tasmania in southern Australia and in New Zealand.
Pogonatum urnigerum is a species of moss in the family Polytrichaceae, commonly called urn haircap. The name comes from "urna" meaning "urn" and "gerere" meaning "to bear" which is believed to be a reference made towards the plant's wide-mouthed capsule. It can be found on gravelly banks or similar habitats and can be identified by the blue tinge to the overall green colour. The stem of this moss is wine red and it has rhizoids that keep the moss anchored to substrates. It is an acrocarpous moss that grows vertically with an archegonium borne at the top of each fertilized female gametophyte shoot which develops an erect sporophyte.
Vittaria appalachiana, or the Appalachian shoestring fern, is a fern species in the subfamily Vittarioideae of the family Pteridaceae. It is native to moist and shaded outcrops in the Appalachian Mountains. It is notable for existing only in the gametophyte stage of development, unlike other fern species in which the sporophyte stage predominates. The species reproduces asexually through gemmae.
Andreaea blyttii, also commonly known as Blytt's rock moss, is a moss belonging to the family Andreaeaceae, commonly known as rock moss, granite moss, or lantern moss because of this family's unique sporangium. It is part of the genus Andreaea which is known for forming dark brownish or reddish-black carpets in high elevations. This species was first described by Schimper in 1855.
Symphyogyna podophylla is a dendroid liverwort which is widespread in wet forests. It occurs in New Zealand, South America, Southern Africa, and is very common in wet forests of Australia and Tasmania.