Mitthyridium constrictum

Click the yellow dot to see these synapomorphies (click any yellow dot to see a clade's characters)

Gemmae characters: gemmae smooth

Margin characters: number of border cell columns evolves from 7 to 30+; margin involute/constricted

Leaf characters: leaf tip rhizoids present

Indel characters: indel 1, 2, 6 and 8 evolve.

Mitthyridium constrictum

Range Map

This clade is the most widespread in Mitthyridium though rare where found. Its range extends from the Malay Peninsula east to Tahiti

Description

Lineage: Mitthyridium constrictum

Latin name: Mitthyridium constrictum (Broth.) Robinson
Synonyms:
Calymeres constrictum Sull.
Syrrhopodon tubulosus Broth.
Thyridium constrictum (Sull.) Mitt.

General description:
Plants robust and yellow-green in color. Branches very large and often reaching 5 cm. Leaves 2.5-3 mm long and with broadly spreading shoulders. The lamina is ovate and the apex is tubular funnel-shaped forming a receptacle (that often does bear gemmae). Stereome (border of hyaline cells) is the broadest of any member of Mitthyridium with the number of marginal cell columns reaching 40. The margin covers nearly the whole leaf ending at the constricted apex. Cancellinae typically occupying 1/2 the total leaf length and typically composed of 18 cell columns. Sporophytes are common in western/continental members of the group; seta length typically 7-8 mm. They are found only on members in the western expanses of its range; no member of this clade is known to be sporophytic in the eastern islands of the South Pacific.

Diagnostic phylogenetic characters: [move the cursor over the image to view the morphological matrix]

The texture of the gemmae is smooth. The cancellinae are on average 18. The cancellinae compose 1/2 of the total leaf (as in its close relative, crassum). The cancellinae/laminal transition is of the basal form, state 0 (also as in crassum). The number of marginal cell columns >30. The large margin extends nearly the entire length of the leaf. Margins are strongly inrolled towards apex and forming a receptacle. The lamina cells produce large singular papillae/mamillae. The clade commonly produce gemmae. Like crassum the costa in cross-section can often have 4 guide cells of equal size(where in all other clades in Mitthyridium the number of guide cells of equal size is two).

Diagnostic phylogenetic characters (synapomorphies and/or autapomorphies) were assessed by optimizing via ACCTRAN morphological characters to the 80 taxon total evidence phylogeny decribed in the Phylomonography&Mitthyridium section bulleted above.