Monographs Details: Asterella dominicensis S.Arn.
Authority: Bischler, Hélène, et al. 2005. Marchantiidae. Fl. Neotrop. Monogr. 97: 1--262. (Published by NYBG Press)
Family:Aytoniaceae
Synonyms:Asterella evansii Del Ros.
Description:Species Description - Thallus flat, delicate (hygroshoots) or narrower and somewhat leathery (xeroshoots), 2.5-5 mm broad, green, often tinged purplish below and on margins; branching mostly of terminal dichotomies and terminal adventitious branches. Epidermal cells thin-walled in hygroshoots, thick-walled and with trigones in xeroshoots. Epidermal pores with 3-4 concentric rings of cells in 5-8 rows. Air chambers large, in 1-2 layers. Ventral scales wine-red, asymmetrical, with scattered oil cells and 1 marginal papilla, with 1 lanceolate appendage 2-4 cells broad at base, ending in 2-3 uniseriate cells. Antheridia in small cluster surrounded when young by scales, on long or short (sometimes very short and appearing lateral) terminal branches, sometimes several along margin of main thallus. Archegoniophore borne in apical notch on main thallus, stalk delicate, 10-15(-35) mm long; receptacle conical when young, becoming umbrella-shaped when mature, shortly 3-to 5-lobed. Involucre flaplike, entire. Pseudoperianth usually hyaline, divided into 7-12 lanceolate lobes that become free at apex. Spores yellow, 60-85 Jim diam., sculpturing dissimilar on distal and proximal faces, distally with 4-6 large areoles across face, areoles alveolate within, muri rounded in section, proximal facets alveolate, wing weakly differentiated. Elaters with 2 helical bands. Gametophytic chromosome number unknown.

Discussion:Notes: Some plants from Mexico have spores with the distal areoles less well developed, but in other respects the plants are typical.

Distribution and Ecology: Asterella dominicensis is known from C America (Mexico, Guatemala, Costa Rica), the Dominican Republic in the Greater Antilles, and Venezuela, but is probably commoner than records suggest. It grows in moist shaded habitats on soil, in rock crevices and under boulders, on damp banks often near streams, in montane forests especially Pinus and Abies, mostly between 2000 and 3000 m altitude. Its appearance and microhabitat preferences are similar to that of the next species, but it occurs in cooler forests at higher altitude.

Distribution:Puntarenas Costa Rica Central America| Veracruz Mexico North America| Querétaro Mexico North America| Distrito Federal Mexico North America| Durango Mexico North America| Morelos Mexico North America| México Mexico North America| Michoacán Mexico North America| Puebla Mexico North America| Quiché Guatemala Central America| Mérida Venezuela South America| El Seibo Dominican Republic South America|