Marchantia breviloba A.Evans

  • Authority

    Bischler, Hélène, et al. 2005. Marchantiidae. Fl. Neotrop. Monogr. 97: 1--262. (Published by NYBG Press)

  • Family

    Marchantiaceae

  • Scientific Name

    Marchantia breviloba A.Evans

  • Type

    Type. Jamaica. Jul 1903, Evans 175 (holotype, YU).

  • Description

    Species Description - Thallus light to yellowish green, usually 4.6-6.6 mm wide, without distinct median band on dorsal side; margins light red or purplish, seldom hyaline, marginal cells hardly thickened. Epidermal pores usually 74-106 µm diam., inner opening bordered by cells with strongly convex inner walls. Basal tissue with red sclerotic cells and numerous mucilage cavities. Ventral scales in 4 rows; appendage of median scales orange or purplish, seldom hyaline, ovate or orbicular (length/width ratio usually 1-1.2:1), 11-18 cells wide, with lower edges often folded over, apex rounded, obtuse, bluntly acute and shortly apiculate, margins irregularly angular, or crenulate, marginal cells sinuose, usually 1.7-4.3 times smaller than inner cells, oil cells absent; laminal scales purplish or hyaline. Cupules regularly ciliate, cilia 2-4(-6) cells long, outer side without papillae. Stalks of gametangiophores without conspicuous scales basally. Antheridiophore stalk with single, narrow, often interrupted band of air chambers or without band, with 2-4 rhizoid furrows; receptacle palmate, usually 5.9-9.3 mm diam., deeply dissected into (2-)4-8 irregular rays, without papillae on dorsal side. Archegoniophore stalk with single, broad band of air chambers and 4(-2) rhizoid furrows; receptacle usually 4.5-6.9 mm diam., concave or with very shallow median projection, nearly symmetrical, shallowly dissected into (7-)9-11 apically not broadened lobes; scales of receptacle without sinuose cells apically. Involucres with 3-8 cells long cilia at the margins. Spores brown, seldom yellow, usually 30-36 µm diam., with tuberculate areoles. Gametophytic chromosome number n = 18.

  • Discussion

    The species has been collected on soil and rocks, at water edges, along wet road banks, or along tracks, in tropical rainforest. It grows from 500 m to 4000 m, but mostly above 1000 m.

    The appendages of the scales of M. breviloba are similar in shape to those of M. paleacea. However, the epidermal pores are not cruciate in M. breviloba and the cupules are ciliate, not provided with ciliate lobes. Male and female receptacles yield additional distinctive characters. Marchantia breviloba is distinguished from M. chenopoda and M. inflexa by the appendages of the median scales, which are much longer than wide in M. chenopoda and coarsely toothed in M. inflexa.

    Marchantia breviloba is the sole neotropical Marchantia species with a duplicated gametophytic chromosome set. Sometimes, male branches develop between the lobes in the female receptacles.

    Distribution and ecology: Marchantia breviloba is a species restricted to the Neotropics, where it occurs scattered between 20°N and 23°S. It has been recorded from Cuba, Jamaica, Haiti, Colombia (Boyacá, Cundinamarca, Norte de Santander), Venezuela (Mérida), Ecuador (Pichincha), Peru (Amazonas, Cajamarca, Cuzco, Junín (Bryan, 1929), San Martín), Brazil (Rio de Janeiro), and Bolivia (Cochabamba). It seems to be absent from C America and the Leeward and Windward Islands.

  • Distribution

    Rio de Janeiro Brazil South America| Haiti South America| Cochabamba Bolivia South America| Pichincha Ecuador South America| Amazonas Peru South America| Cajamarca Peru South America| Cusco Peru South America| San Martín Peru South America| Mérida Venezuela South America| Boyacá Colombia South America| Cundinamarca Colombia South America| Norte de Santander Colombia South America| Saint Andrew Jamaica South America| Santiago de Cuba Cuba South America| Saint Catherine Jamaica South America| Kingston Jamaica South America|