''Anthoceros agrestis'', commonly called field hornwort, is a bryophyte of the family

Anthocerotaceae The Anthocerotaceae is the only family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social o ...

. ''A. agrestis'' is considered the model species for hornwort biology and is used to study some of the unique traits that hornworts possess, such as their symbiotic relationship with

nostoc ''Nostoc'', also known as star jelly, troll's butter, spit of moon, fallen star, witch's butter (not to be confused with the fungi commonly known as witches' butter), and witch's jelly, is the most common genus of cyanobacteria found in a variety ...

and their use of pyrenoids to enhance photosynthesis. Anthoceros agrestis 060910d

Description

''Anthoceros agrestis'' grows as a thin, dark green, rosette-like

thallus Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entir ...

up to in diameter, superficially resembling a leafless

liverwort Liverworts are a group of non-vascular land plants forming the division Marchantiophyta (). They may also be referred to as hepatics. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry ...

. The surface is punctured with hollows containing the male organs. The spore-producing bodies lack a stalk or capsule but produce erect, cylindrical structures that turn black as they mature. They then split open to reveal the spore-bearing central spindle and release the black spores.

Distribution and habitat

This hornwort has a circum-boreal distribution across temperate Europe and North America. It is a lowland species found in moist soil in arable fields and ditches. It is listed as vulnerable in the Irish Red Data Book as it is known from fewer than five locations in the country. It occurs at a single location in Northern Ireland, in

County Down County Down () is one of the six counties of Northern Ireland, one of the nine counties of Ulster and one of the traditional thirty-two counties of Ireland. It covers an area of and has a population of 552,261. It borders County Antrim to the ...

, and because of its rarity there, it is listed as a Northern Ireland Priority Species.

Chemistry

This species of ''

Anthoceros ''Anthoceros'' is a genus of hornworts in the family Anthocerotaceae. It is distributed globally. Species of ''Anthoceros'' are characterized by having a small to medium-sized, green thallus that is more or less lobed along the margins. Etym ...

'' is known for having enzymes like cinnamic acid 4-hydroxylase (EC 1.14.13.11), a

cytochrome P450 Cytochromes P450 (P450s or CYPs) are a Protein superfamily, superfamily of enzymes containing heme as a cofactor (biochemistry), cofactor that mostly, but not exclusively, function as monooxygenases. However, they are not omnipresent; for examp ...

-dependent hydroxylase. It is one of the first known plant cytochrome P450 monooxygenases and also one of the best-characterized cytochrome P450 hydroxylases from higher plants. Production of rosmarinic acid and a rosmarinic acid 3'-O-beta-D-

glucoside A glucoside is a glycoside that is chemically derived from glucose. Glucosides are common in plants, but rare in animals. Glucose is produced when a glucoside is hydrolysed by purely chemical means, or decomposed by fermentation or enzymes. Th ...

in suspension cultures of this

hornwort Hornworts are a group of non-vascular Embryophytes (land plants) 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 ...

was also discovered in 2005. Anthocerodiazonin, an

alkaloid Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids. Alkaloids are produced by a large varie ...

, was isolated from in vitro cultures of the species. Also, six glutamic acid amides, N-(4-hydroxybenzoyl)-glutamic acid, N-(3,4-dihydroxybenzoyl)-glutamic acid, N-(4-hydroxy-3-methoxybenzoyl)-glutamic acid, (E)-N-(isoferuloyl)-glutamic acid, (Z)-N-(isoferuloyl)-glutamic acid and (Z)-N-(p-coumaroyl)-glutamic acid were obtained as natural products.

References

{{Taxonbar, from=Q341574 Hornworts Flora of the Holarctic realm Bryophyta of North America Plants described in 1979