| | The liverwort genera (Bryophyta: Hepaticae and Anthocerotae) of Britain and Ireland |
Gametophyte. Plants thalloid, not leafy (the thallus usually pale green with crisped margins, the epidermis with stomata). Anacrogynous (borne singly on the dorsal surface of the thallus).
The cells of the gametophyte each with a single, large chloroplast. The thallus variously, irregularly lobed; without a conspicuous conducting strand; without ventral scales; containing conspicuous cavities (these numerous, mucilage-filled or containing Nostoc colonies and visible dorsally as dark spots).
The plants bisexual (monoecious).
Sporophyte. The sporophyte elevated via an intercalary meristem. The capsule elongate-cylindrical; with a central, longitudinal columella; green; dehiscing via two valves. The spores dark brown or blackish, unicellular when shed. Elaters present; mostly bent, (1-)2-several celled (‘pseudo-elaters’); without spiral thickenings; free.
British representation. 2 species; England, Wales, Scotland, and Ireland.
Classification. Class/Division Anthocerotae. Order Anthocerotales. Family Anthocerotaceae.
Illustrations. • A. agrestis (as crispulus): Jameson, in Macvicar (1926). • A. punctatus: Jameson, in Macvicar (1926). • A. punctatus: Pearson fig. CCXXVII (1902). • A. punctatus: Pearson fig. CCXXVII legend. • A. punctatus forma stableri (as A. stableri): Pearson fig. CCXXVIII (1902). • A. punctatus forma stableri (as A. stableri): Pearson fig. CCXXVIII legend.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2005 onwards. The liverwort genera (Bryophyta: Hepaticae and Anthocerotae) of Britain and Ireland. Version: 5th August 2019. delta-intkey.com’.
