GAMETOFITOS Y ESPOROFITOS JÓVENES DE DOS PTERIDOFITAS: ASPLENIUM MONANTHES L. (ASPLENIACEAE-PTERIDOPHYTA) Y ELAPHOGLOSSUM MINUTUM (POHL EX FÉE) T. MOORE (LOMARIOPSIDACEAE-PTERIDOPHYTA)*

Abstract

We describe the life cycles of Asplenium
monanthes L. and Elaphoglossum minutum
(Pohl ex Fée) T. Moore. The first species
was collected from Tres Marías, Morelos,
Mexico, in montane rain forest, the second
from Parque Nacional El Chico, Hidalgo,
in Pinus-Abies forest. Spores were sown in
glass flasks prepared in the following manner: the flasks were layered with ceramic,
river stone, mosquito net, ground maquique
(adventitious roots from tree fern trunks)
and water. All the material was sterilized.
The flasks were sealed with plastic bags
and tied with copper wire. The germination
pattern of both species is of the Vittaria type,
and the prothallial development is of the Aspidium type. Both cycles are isosporous. The
gametophyte of E. minutum is at first heartshaped, but by the time it reaches maturity
it has taken on an elongate form with many
ventral, dorsal and marginal rhizoids.
In both species the cycles develop very
slowly. In Asplenium sporophytes appear
at 349 days and in Elaphoglossum at 350
days, making these species ill-suited for
commercial exploitation.