Dumortiera hirsuta (Sw.) Nees

  • Authority

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

  • Family

    Wiesnerellaceae

  • Scientific Name

    Dumortiera hirsuta (Sw.) Nees

  • Type

    Type (Grolle, 1976). Jamaica. Swartz s.n. (holotype, S; isotype MW, UPS) (n.v.).

  • Synonyms

    Marchantia irrigua Wilson ex Hook., Hygrophila irrigua (Wilson ex Hook.) Taylor, Hygrophila nepalensis Taylor, Dumortiera nepalensis (T.Taylor) Nees, Dumortiera hirsuta var. trichopus Spruce, Marchantia hirsuta Sw.

  • Description

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    Species Description - Thallus 8-30 mm wide, flat, deep green, not tinged with purple. Branching dichotomous and apical. Epidermal pores absent, or at thallus apex only, bounded by a single ring of 4 cells, radial walls thin. Air chambers absent, or in 1 layer and vestigial, with chlorophyllose filaments not roofed by epidermis. The floor of the air chambers becomes the exposed surface of the mature thallus. Basal tissue with few oil cells, without mucilage cavities. Bristles present on ventral thallus side and on gametangiophores. Ventral scales in 2 rows, small, hyaline, without oil cells, papillae, or appendage. Asexual reproduction by specialized propagules lacking. Monoecious or dioecious. Antheridiophores with disk-shaped receptacle, with small ventral scales underneath and bristles on margins and dorsal side, stalk short, without assimilatory strip, with 2 rhizoid furrows; rarely, antheridial branches develop in the female receptacles. Archegonia in stalked, terminal archegoniophores, up to 7 per archegonial cavity. Archegoniophore stalk long, without assimilatory strip, with 2 rhizoid furrows and small scales at top; receptacle shallowly 6- to 16-lobed, without or with few epidermal pores, sometimes with open cavities bounded by a ring of 8-13 cells, with bristles on margins and dorsal side. Calyptrae 2- to 3-layered after fertilization. Involucres tubular, opening at top by a ventral-terminal slit, with bristles. Pseudoperianths lacking. Sporophytes 1-2 or more per involucre with slightly elongating seta. Capsules splitting into 4-8 irregular valves to 3/4 of capsule length. Spore/elater ratio more than 4:1. Spores to 20,000 per capsule, 20-35 µm diam., distal and proximal faces tuberculate, trilete scar distinct. Elaters with 2-4 helical bands. Gametophytic chromosome number n = 9, 18, or 27.

  • Discussion

    The species is very common and has been collected in the Neotropics on moist soil, dripping or mossy rocks, usually in shaded places, on stream-sides, near waterfalls, in caves, in disturbed and undisturbed montane rain forests, from 150 to 3500 m, more commonly below 2000 m.

    Dumortiera hirsuta probably is a complex species, comprising several genetically distinct siblings. Three cytotypes are known, but chromosome counts are not available for neotropical material. Important genetic differentiation has been found within the haploid cytotype, but the large distribution of the species and its rarity in Europe and the Mediterranean precluded a thorough investigation of its genetic structure. Awaiting further research, all neotropical specimens have been attributed to Dumortiera hirsuta sensu lato, thus including D. nepalensis (Tayl.) Nees (Evans, 1919a). This species, treated as a subspecies by Schuster (1992b), is characterized by crowded, papilliform cells on the dorsal surface of the thallus that correspond to remnants of air chamber partitions.

    Dumortiera hirsuta is easily distinguished from most neotropical Marchantiales by its large, dark-green thallus without epidermal pores and with "bristles" on the ventral side. However, in sterile condition the species may be difficult to distinguish from Monoclea gottschei (see under the latter species).

  • Distribution

    Dumortiera hirsuta has been recorded from tropical and warm-temperate areas: from W Europe up to Great Britain and Ireland, the Mediterranean area, Macaronesia, Africa (Ethiopia, tropical Africa, S Africa), the Mascarenes, Asia (from India and Sri Lanka, to E Asia, Japan, and Taiwan), the tropical Asiatic islands, Oceania, and New Zealand. The species is known from 19 states in the United States and is common in the Neotropics.

    Puntarenas Costa Rica Central America| Jamaica South America| Guadeloupe South America| Martinique South America| Dominica South America| Barbados South America| Dominican Republic South America| Haiti South America| Nicaragua Central America| Veracruz Mexico North America| Tamaulipas Mexico North America| San Luis Potosí Mexico North America| Querétaro Mexico North America| Hidalgo Mexico North America| Morelos Mexico North America| Jalisco Mexico North America| Chiapas Mexico North America| Oaxaca Mexico North America| Puebla Mexico North America| Guanacaste Costa Rica Central America| Heredia Costa Rica Central America| Chinandega Nicaragua Central America| Caldas Colombia South America| Chocó Colombia South America| Cundinamarca Colombia South America| Magdalena Colombia South America| Meta Colombia South America| Costa Rica South America| Fajardo Puerto Rico South America| Santiago Dominican Republic South America| Puerto Plata Dominican Republic South America| Jayuya Puerto Rico South America|