Plagiochasma crenulatum Gottsche

  • Authority

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

  • Family

    Aytoniaceae

  • Scientific Name

    Plagiochasma crenulatum Gottsche

  • Type

    Type. Mexico. Veracruz: Orizaba, Muller s.n. (holotype, STR p.p.; isotypes, G p.p., YU).

  • Synonyms

    Aytonia crenulata (Gottsche) Underw.

  • Description

    Deprecated: mb_convert_encoding(): Handling HTML entities via mbstring is deprecated; use htmlspecialchars, htmlentities, or mb_encode_numericentity/mb_decode_numericentity instead in /home/emu/nybgweb/www-dev/htdocs/science-dev/wp-content/themes/nybgscience/lib/VHMonographsDetails.php on line 179

    Species Description - Thallus 5.3-6.7 mm wide, light or yellowish green, with red or purplish, narrow margins. Apical adventitious branches infrequent. Epidermis smooth, epidermal cells 31-40 × 24-28 µm, walls usually with large, nodulose trigones. Epidermal pores 2766 per mm2, slightly raised above epidermis, 21-24 µm diam., bounded by 2-3 concentric rings of 6-7 (-8) cells with slightly thickened radial walls. Ventral scales purplish, bordered by 2-3 rows of light-red or hyaline, sinuose cells; appendage 1, rarely 2, ovate or rounded, hyaline, sometimes light red or yellowish in the central part, length/width ratio 0.8-1.3:1; obtuse, acute or apiculate apically, largest in the middle, 22-26 cells wide, constricted and plicate basally, margins crenulate or toothed, with several rows of sinuose cells, some with papillae. Male receptacles dorsal, usually reniform, with 20-25 antheridia. Scales of male and female receptacles hyaline or partly purplish, acute or apiculate, with crenulate or remotely toothed margins. Archegoniophores dorsal, stalk 0.8-5 mm long, with thickened, red or brown epidermal cells. Involucres 1-3, yellow, purplish or brown. Spores 70-78 µm diam., dark yellow or brown, areolate; areoles and ridges tuberculate. Elaters with 2-4 helical bands. Gametophytic chromosome number n = 18.

  • Discussion

    Plagiochasma crenulatum is a polyploid species. It is distinguished from other neotropical species by the wide, rounded or ovate appendages of the ventral scales.

  • Distribution

    A species found in scattered localities (10°-33°N), quite common in S Mexico. Known from C Alabama, S Arizona, Mexico (Chiapas (Bourrell, 1992), Hidalgo, Morelos, Nuevo León, Oaxaca, Puebla, San Luis Potosí, Sonar, Veracruz), Guatemala, Honduras, and Costa Rica (Cole, 1984), growing in rock and wall crevices, in dry and warm areas, from 650 to 2000 m.

    Veracruz Mexico North America| San Luis Potosí Mexico North America| Querétaro Mexico North America| Hidalgo Mexico North America| Morelos Mexico North America| Nuevo León Mexico North America| Oaxaca Mexico North America| Sonora Mexico North America| Puebla Mexico North America| Alta Verapaz Guatemala Central America| Izabal Guatemala Central America| Comayagua Honduras Central America|