Lunularia cruciata.jpg
   HOME

TheInfoList



OR:

''Lunularia cruciata'', the crescent-cup liverwort, is a liverwort of the order Marchantiales (until recently included in the
order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...
Lunulariales), and the only species in the genus ''Lunularia'' and family Lunulariaceae. The name, from Latin ''luna'', moon, refers to the moon-shaped gemma cups.


Distribution

''L. cruciata'' is distributed across the world, found in continents including Europe, Australasia, Asia, the
Americas The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with th ...
, and Africa. It occurs commonly in western Europe, and is native to the Mediterranean region, where the morphological forms from sexual reproduction are more frequently found there. It is also common in California, where it now grows "wild", and is known as an introduced weed in gardens and greenhouses in
Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
.Schuster, Rudolf M. ''The Hepaticae and Anthocerotae of North America'', volume VI, pages 80-91. (Chicago: Field Museum of Natural History, 1992). .
Ella Orr Campbell Dame Ella Orr Campbell (28 October 1910 – 24 July 2003) was a New Zealand Botany, botanist. An expert on bryophytes, she published 130 scientific papers on liverworts, hornworts, orchids, and wetlands. She became the first woman faculty membe ...
believed that ''L. cruciata'' was introduced into New Zealand sometime after 1867. The
sporophyte 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. Life cycle The sporophyte develops from the zygote pr ...
s of ''L. cruciata'' are rare, but has been found in European regions, as well as in South Africa, Argentina, California, India,
Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
and New Zealand.


Habitat and ecology

''L. cruciata'' grows in damp, shaded and disturbed habitats such as path and wall edges. It can act as a nutrient indicator because it often grows in alkaline and eutrophic to highly eutrophic soil. Other habitats include
loam Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–sil ...
, boulders, concrete, exposed tree roots, soil covered logs and in the gaps between sidewalk stones. ''L. cruciata'' also grows as a horticultural weed in gardens, greenhouses and parks. ''L. cruciata'' is sensitive to frost, and is often found near water, where its gemmae are washed ashore.


Morphology

''L. cruciata'' grows large, dichotomously branched green thalli with crescent shaped gemma cups containing disc like gemmae. This is a unique morphological characteristic not possessed by other thalloid liverworts. Its thallus surface is shiny, faintly lined, and is dotted with tiny air pores. When dried the thallus turns yellowish in color and its margin rolls inward.


Reproduction

As in other liverworts, the main plant body or thallus is a
haploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively ...
gametophyte. The antheridia of ''L. cruciata'' develops in early spring, the
archegonia An archegonium (pl: archegonia), from the ancient Greek ''ἀρχή'' ("beginning") and ''γόνος'' ("offspring"), is a multicellular structure or organ of the gametophyte phase of certain plants, producing and containing the ovum or female ga ...
develops in spring and sporophytes develop in late summer. However, records of sporophyte developments and sexual reproduction are rare and scattered. This was suspected to have been the result of the anthropogenic spreading of this species, causing a disjunctive distribution of antheridia and archegonia. When reproducing sexually, the four archegonia is arranged in a cross-shaped head (hence the specific name ''cruciata'') bearing
diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively ...
sporophyte plantlets. When reproducing asexually, the disc-shaped gemmae are readily dislodged from the cups by splashes of rainwater. They can then quickly "take root" and start to grow in suitably damp places, which is why they are so successful in greenhouses.


Chemical properties

Like many other liverwort species, ''L. cruciata'' produces a dihydrostilbenoid growth hormone,
lunularic acid Lunularic acid is a dihydrostilbenoid found in the liverwort ''Lunularia cruciata'' and in the roots of ''Hydrangea macrophylla''. A lunularic acid decarboxylase has been detected from the liverwort ''Conocephalum conicum ''Conocephalum conicu ...
, that is reported to be a growth inhibitor of liverworts. Cadmium in this liverwort also inhibits gemma germination and apical thallus growth, as well as altering cell and
chloroplast A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in ...
structure. Acetone extracts from ''L. cruciata'' were tested and showed antibacterial properties, but had no effects against fungal activity.


References


External links

*
USDA information

Photos


{{Taxonbar, from1=Q1474234, from2=Q21441194, from3=Q17276679, from4=Q17276680 Liverworts Monotypic bryophyte genera Bryophyta of North America Flora of Europe Flora of California Flora of New Zealand Liverwort genera