Monographs Details: Marchantia inflexa Nees & Mont.
Authority: Bischler, Hélène, et al. 2005. Marchantiidae. Fl. Neotrop. Monogr. 97: 1--262. (Published by NYBG Press)
Synonyms:Marchantia disjuncta Sull., Marchantia elliottii Steph., Marchantia caracensis Steph.
Description:Species Description - Thallus green to light green or glaucous, without or with weak purplish pigmentation, usually 2.8-4.2 mm wide, usually without distinct median band on dorsal side; margins hyaline, marginal cells thin-walled. Epidermal cells without papillae. Epidermal pores usually 60-92 µm diam., inner opening bordered by cells with straight to slightly convex inner walls. Basal tissue with scattered oil cells and purplish sclerotic cells, with or without mucilage cavities. Ventral scales in 4 rows; appendage of median scales purplish, light red or orange, broadly triangular (length/width ratio usually 1-1.6:1), usually 10-14 cells wide, acute or shortly apiculate apically, margins nearly regularly toothed, with 1- to 2-celled teeth, marginal cells usually 1.5-3.7 times smaller than inner cells, oil cells rare; laminal scales purplish or light red, rarely hyaline. Gemma cups with irregular cilia 1-3(-4) cells long, outer side without papillae. Stalks of gametangiophores without conspicuous scales basally. Antheridiophore stalk with single, narrow, often interrupted band of air chambers, and 2(-4) rhizoid furrows; receptacle palmate, usually 4.7-7.1 mm diam., deeply dissected into 4-6(-7) rays, with few, scattered papillae on dorsal side, or papillae absent. Archegoniophore stalk with single, broad band of air chambers and 2(-4) rhizoid furrows; receptacle usually 3.3-5.3 mm diam., symmetrical or slightly asymmetrical, with hardly distinct median projection dorsally, deeply dissected into 5-9(-11) lobes, not or slightly broadened apically; scales of receptacle without sinuose marginal cells apically. Involucres at margins crenulate or with irregular cilia 1-2 cells long. Spores yellowish or brown, usually 25-29 µm diam, with tuberculate areoles. Gametophytic chromosome number n = 9.

Discussion:Marchantia inflexa is most closely allied to M. papillata and has been considered a synonym of the latter by many authors (e.g., Hassel de Menéndez, 1963). However, the 2 species differ in the shape of the female receptacle, which is more deeply divided and with lobes convex and costate basally, strongly broadened apically and with a conspicuous median projection dorsally in M. papillata. The margins of the cupules and the involucres are shortly ciliate in M. inflexa, whereas they are crenulate in M. papillata. Other characteristics separating M. inflexa from M. papillata are the distinct median band on dorsal side of thallus, with purplish pigmentation of margins, the absence of mucilage cavities, and the spore wall ornamentation in M. papillata. Moreover, the scales of the female receptacle are sinuose apically in the latter species, whereas they are straight in M. inflexa. Their geographical ranges do not overlap.

Sterile Marchantia chenopoda specimens can be distinguished from M. inflexa by their purplish thallus margins, bordered by thick-walled cells.

Distribution and Ecology: Marchantia inflexa is a New World species, known from 36°N to 7°30' N in the U.S.A. (Alabama, Arizona, Arkansas, Florida, Georgia, Louisiana, Oklahoma, Tennessee, Texas), and in the Neotropics from Mexico (Chiapas, Guerrero, Hidalgo, Nuevo Leon, Oaxaca (Dull, 1999), Puebla, Querétaro, Tamaulipas, Veracruz), Guatemala, El Salvador, Nicaragua, Costa Rica, Panama, Bahamas (Britton & Millspaugh, 1920), Cuba, Jamaica, Haiti, Dominican Republic, Puerto Rico, Leeward Is. (St. Kitts, Monserrat Is.), Windward Is. (Guadeloupe, Dominica, Martinique, St. Vincent, Grenada), Colombia (S. Andres Is., Santander), Venezuela (Caracas), Trinidad. It is a common species in the Caribbean area, growing on soil and soil over rocks (limestone, volcanic), in humid and usually shaded places in tropical rainforest under open vegetation, or at water edges, or in seepage areas where it may be intermittently flooded, more rarely on road banks, preferentially at low elevations (below 1000 m) but reaching 3100 m in C America.

Distribution:Montserrat South America| Puerto Rico South America| Cuba South America| Jamaica South America| Guadeloupe South America| Saint Vincent and the Grenadines South America| Martinique South America| Grenada South America| Dominica South America| Dominican Republic South America| Haiti South America| Veracruz Mexico North America| Tamaulipas Mexico North America| Querétaro Mexico North America| Hidalgo Mexico North America| Nuevo León Mexico North America| Guerrero Mexico North America| Puebla Mexico North America| Coclé Panamá Central America| Guanacaste Costa Rica Central America| San José Costa Rica Central America| Ahuachapán El Salvador Central America| San Vicente El Salvador Central America| Alta Verapaz Guatemala Central America| Granada Nicaragua Central America| Distrito Federal Venezuela South America| San Andrés y Providencia Colombia South America| Santander Colombia South America| Portland Jamaica South America| Mexico North America| Costa Rica South America| Saint Elizabeth Jamaica South America| Saint Andrew Jamaica South America| Pedernales Dominican Republic South America| Puerto Plata Dominican Republic South America| Oriente Cuba South America| Arecibo Puerto Rico South America| Cayey Puerto Rico South America| Saint Kitts Saint Kitts and Nevis South America| Trinidad and Tobago South America|