''Andreaea'' is a genus of rock

moss Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hor ...

es described by

Johann Hedwig Johann Hedwig (8 December 1730 – 18 February 1799), also styled as Johannes Hedwig, was a German botanist notable for his studies of mosses. He is sometimes called the "father of bryology". He is known for his particular observations of sexual r ...

in 1801. They are small, delicate acrocarpous mosses (meaning that the capsules are formed at the tips of vertical branches) that form dark brown or reddish cushions on wet

siliceous Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one ...

rocks in mountainous areas. The capsule lacks the peristome teeth and operculum of other mosses, and opens by splitting along 4 vertical slits, the four valves remaining joined at the base and apex. The capsule of ''Andreaea'' has no

seta In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. Th ...

, but 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 ...

(''Spf'' in the diagram below) instead is supported by a

pseudopodium A pseudopod or pseudopodium (plural: pseudopods or pseudopodia) is a temporary arm-like projection of a eukaryotic cell membrane that is emerged in the direction of movement. Filled with cytoplasm, pseudopodia primarily consist of actin filament ...

(''ps'') derived from

gametophyte A gametophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has on ...

tissue, as in ''Sphagnum'' and the

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the wo ...

is enclosed within the

sporangium A sporangium (; from Late Latin, ) is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other lineages form sporangia at some point in their life cy ...

. The spores germinate to give

thalloid Thallus (plural: thalli), from Latinized Ancient Greek, Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some Marchantiophyta, liverworts, lichens, and the Myxogastr ...

protonemata.

Species

In alphabetical order:The Plant List, search for ''Andreaea''
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References

External links

* Zander, Richard H. 2007. ''Bryophyte Flora of North America''

* Universidad Complutense de Madrid. MUSGOS - Biodiversidad y Taxonomía de Plantas Criptógamas

{{Taxonbar, from=Q139017 Andreaeaceae Moss genera