Each of the four species produced sporophytes at the swollen venter stage when
gametangia were mature and gametes were available for fertilisation events.
Young gametophytes and
gametangia of Acrostichum: A) Bidimensional gametophyte of A.
Fungus colonization always occurs through the rhizoids after male
gametangia differentiation.
Devonian gametophytes with anatomically preserved
gametangia. Science 208: 295-296.
When it is known, the ontogeny of the
gametangia start either with the arquegonia, as in B.
The progenesis and acceleration of gametogenesis in flowering plants resulted in the loss of
gametangia (antheridia and archegonia) on their gametophytes.
The length and width of gametophores, as well as the diameter of the
gametangia were clearly different for both species.
Trichomanes intricatum Farrar and Vittaria appalachiana Farrar & Mickel are perennials that reproduce exclusively by gemmae, even though
gametangia may be present.
The
gametangia are typical of the leptosporangiate ferns, sporophytes after six and a half months in culture did not appeared.
Last, in cultures of the moss Bartramidula bartramiodes it was shown that formation of
gametangia, or organs in which the sex cells are produced, did not occur in medium below pH 5 but did occur with increasing frequency at pH levels up to 7 (Rahbar & Chopra, 1982).
Gametangia are of the common type for the leptosporangiate advanced ferns.