The liverwort genera (Bryophyta: Hepaticae and Anthocerotae) of Britain and Ireland
Gametophyte. Plants small to robust, often brownish tinged leafy. Shoots procumbent to erect, usually sparsely branched. The branching conventional. The stems translucent. Acrogynous. The leaf cells mostly thin-walled, with trigones to without trigones. Rhizoids usually present (usually numerous more or less to the stem apices).
The leafy shoots dorsiventral, with two equal ranks of lateral leaves and a third, ventral rank of smaller underleaves (usually, at least on the sterile stems), or dorsiventral, with the two ranks of laterals more or less equal in size and the ventral rank lacking. The vegetative leaves more or less symmetrical. The vegetative leaves obliquely inserted; alternate; overlapping; the dorsal margins decurrent or not, the ventral margins hardly ever ciliate succubous. The leaf margins entire; shortly dorsally decurrent, or not or only slightly dorsally decurrent. The vegetative leaves 1/6–1/3 bilobed (the lobes rounded to acute or obtuse and apiculate, the ventral one often larger than the dorsal); not complicate-bilobed. The ventral lobes similar in size to the dorsal ones. Underleaves smaller than the laterals though well developed and conspicuous, or present but much reduced or vestigial, or absent (usually present on sterile stems, but small, subulate to narrowly lanceolate, simple or bifid, usually with one or more teeth or cilia); bilobed, or not bilobed. The cells of the gametophyte with numerous small chloroplasts. The chloroplast-containing cells with conspicuous oil bodies (mostly 2–5 per cell, opaque). Gemmae common (smooth), or rare.
The plants dioecious, or bisexual; when bisexual, having the gametangia grouped into bracteate inflorescences; paroecious.
Male inflorescences in the few species described by Macvicar and Smith, intercalary or terminal, with 4–8 pairs of saccate, three-lobed or antically one-toothed bracts at the middle of the stems. Female bracts present to absent (similar to the leaves, or larger). Female bracts similar in size to the (upper) leaves, or larger than the (upper) leaves; perianth present; perianth smooth, abruptly contracted to the shortly beaked, denticulate or ciliate mouth. Perianth distally smooth, not plicate (at least, no more than slightly plicate at the rounded apex). Perianth distally beaked, or distally beaked to not beaked (abruptly contracted to shortly beaked).
Sporophyte. The sporophyte elevated by elongation of the seta, with no intercalary meristem. Elaters present (usually brown or reddish-brown); bispirally thickened; free. Ecology. Occurring in basic habitats.
British representation. 7 species; England, Wales, Scotland, and Ireland.
Classification. Class/Division Hepaticae. Subclass/Class Jungermanniidae. Order Jungermanniales. Family Lophoziaceae.
Illustrations. • L. alpestris (as Lophozia muelleri): Jameson, in Macvicar (1926). • L. alpestris (as Jungermania): Pearson fig. CXLII (1902). • L. alpestris (as Jungermania): Pearson fig. CXLII legend. • L. alpestris var. gelida (as Jungermania gelida): Pearson fig. CXLIII (1902). • L. alpestris var. gelida (as Jungermania gelida): Pearson fig. CXLIII legend. • L. badensis (as Lophozia): Jameson, in Macvicar (1926). • L. bantriensis (as Lophozia): Jameson, in Macvicar (1926). • L. bantriensis (as Jungermania) Pearson fig. CXXXIII (1902). • L. bantriensis (as Jungermania) Pearson fig. CXXXIII legend. • cf. L. gillmanii (as Lophozia kaurini): Jameson, in Macvicar (1926). • L. heterocolpos (as Lophozia): Jameson, in Macvicar (1926). • L. incisa (as Jungermania): Pearson fig. CXLIV (1902). • L. incisa (as Jungermania): Pearson fig. CXLIV legend. • L. muelleri (as Jungermania bantriensis var. muelleri): Pearson fig. CXXXXIV (1902). • L. muelleri (as Jungermania bantriensis var. muelleri): Pearson fig. CXXXXIV legend). • L. rutheana (as Lophozia schultzii): Jameson, in Macvicar (1926). • L. turbinata (as Lophozia): Jameson, in Macvicar (1926). • L. turbinata (as Jungermania): Pearson fig. CXXXII (1902). • L. turbinata (as Jungermania): Pearson fig. CXXXII legend.
To view the illustrations with detailed captions, go to the interactive key. This also offers 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.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2005 onwards. The liverwort genera (Bryophyta: Hepaticae and Anthocerotae) of Britain and Ireland. Version: 24th February 2016. delta-intkey.com’.