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| The liverwort genera (Bryophyta: Hepaticae and Anthocerotae) of Britain and Ireland |
~ Lophozia Dum.
Gametophyte. Plants variously forming tufts, patches or comprising scattered shoots, leafy. The stems procumbent to erect, simple or branched. Acrogynous. The leaf cells without trigones. Rhizoids present; colourless; of one kind, all smooth.
The leafy shoots dorsiventral, with two equal ranks of lateral leaves and a third, ventral rank of smaller underleaves (mostly), or dorsiventral, with the two ranks of laterals more or less equal in size and the ventral rank lacking; not julaceous. The vegetative leaves generally more or less symmetrical (but more asymmetrical in B. lycopodioides). The vegetative leaves transversely inserted to obliquely inserted; alternate; overlapping to distant; with the dorsal margin more or less decurrent, the ventral with or without basal cilia, succubous. The leaf margins not multi-ciliate. The vegetative leaves several-lobed (mostly 3–4 lobed, from less than a quarter to about halfway, the lobes sometimes obtuse but more often cuspidate or even bristle-pointed); not complicate-bilobed; without vittae. Underleaves smaller than the laterals though well developed and conspicuous, or present but much reduced or vestigial (usually present at least on sterile stems and large, deeply bifid and ciliate, but occasionally small and subulate); not bilobed (mostly 3–4 lobed). The cells of the gametophyte with numerous small chloroplasts. The chloroplast-containing cells with conspicuous oil bodies (usually 4–9 per cell). Gemmae common, or rare to absent; when present, 1–2 celled and angular, on the margins of young leaves.
The plants dioecious.
Male inflorescences with bracts terminating stems or intercalary, usually several pairs, concave and basally saccate. Male bracts subtending 2 antheridia, or several antheridia (2–5). Female bracts present (usually larger than the leaves, erect or embracing the perianth). Bracteole present. Perianth present; ovoid to pyriform, gradually contracted to the ciliate mouth. Perianth deeply distally plicate.
Sporophyte. The sporophyte elevated by elongation of the seta, with no intercalary meristem. The capsule ovoid; dehiscing by four valves (brown). The spores unicellular when shed. Elaters at least sometimes present; bispirally thickened; ofen brown, free.
British representation. 8 species; England, Wales, Scotland, and Ireland.
Classification. Class/Division Hepaticae. Subclass/Class Jungermanniidae. Order Jungermanniales. Family Lophoziaceae.
Comments. Unconvincingly separable from Tritomaria (q.v.) via the descriptive data compiled here, exemplifying unsatisfactory, sensu stricto generic circumscriptions accepted by Smith in the Lophoziaceae. Illustrations. • B. atlantica (as Lophozia): Jameson, in Macvicar (1926). • B. attenuata (as Lophozia): Jameson, in Macvicar (1926). • B. attenuata (as Jungermania gracilis): Pearson fig. CXLVII (1902). • B. attenuata (as Jungermania gracilis): Pearson fig. CXLVII legend. • B. barbata (as Lophozia): Jameson, in Macvicar (1926). • B. barbata (as Jungermania): Pearson fig. CXLVIII (1902). • B. barbata (as Jungermania): Pearson fig. CXLVIII legend. • B. floerkii (as Lophozia): Jameson, in Macvicar (1926). • cf. B. floerkii (as Jungermania lycopodioides var. floerkii): Pears fig. CL (1902). • cf. B. floerkii (as Jungermania lycopodioides var. floerkii): Pears fig. CL legend. • B. hatcheri (as Lophozia): Jameson, in Macvicar (1926). • B. kunzeana (as Lophozia): Jameson, in Macvicar (1926). • B. kunzeana (as Jungermania): Pearson fig. CLI (1902). • B. kunzeana (as Jungermania): Pearson fig. CLI legend. • B. lycopodioides (as Lophozia): Jameson, in Macvicar (1926). • B. lycopidioides (as Jungermania): Pearson fig. CXLIX (1902). • B. lycopidioides (as Jungermania): Pearson fig. CXLIX legend. • B. quadriloba (as Lophozia): Jameson, in Macvicar (1926).
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’.
