Fissidens inclusus Bizot & Dury ex Pócs

Bruggeman-Nannenga, Maria Alida, 2022, On the peristomes of the corticolous African species of Fissidens Hedw. (Fissidentaceae, Bryophyta), Cryptogamie, Bryologie 20 (2), pp. 9-36 : 20-22

Fissidens inclusus Bizot & Dury ex Pócs

( Fig. 9 )

Fissidens inclusus is characterized by short, 0.7-0.8 mm long, setae, vaginant laminae with revolute margins, mammillose cells, limbidia restricted to the upper leaves of perichaetial stems and divided peristomes. It is closely related to F. pocsii Bizot & Dury ex Pócs sensu lato. For differences see under that species. Growing on twigs in loose pure mat.

Peristome

Erect to curved inwards when wet, divided, often broken off; teeth 122-166 µm long, at the base 20-29 µm wide.

Ornamentation

OPL undivided part ±8 cells tall, with high, thin, smooth trabeculae and finely papillose lamellae; around bifurcation trabeculae distinct and lamellae with sparse ornamentation of oblique ridges; IPL basal 4 cells with high trabeculae and

±smooth (hard to see) lamellae; bifurcation with high oblique ridges; both OPL and IPL of filaments with dense ornamentation of oblique ridges (“spiral”). This peristome resembles a weak bryoides - type peristome with short filaments. The bryoides - type peristome is diagnostic for subgenus Fissidens . Fissidens inclusus however, has a subgen. Polypodiopsis gametophyte. This problem is considered later in the discussion.

Sporophyte

Seta 0.7-0.8 mm long, smooth to ± rough; capsule cylindrical to narrowly cylindrical, 0.6-0.7 × 0.3-0.35 mm, exothecial cell columns ± 32, the cells oblong, operculum not observed, spores (17.5-)19-25(-28) × 15.5-23 µm (almost smooth).

Description

Bizot (1974: 132).

Figures

FIG. 9. — Fissidens inclusus Bizot & Dury ex Pócs. A, capsule mouth with peristome. Four teeth on the left and three on the right seen from the OPL-side, in the mid IPL of pair of teeth; B, OPL of undivided part and bifurcation; C, IPL basal part and basal filaments plus spore;D, IPL distal filaments; E, capsule (moist) with straight erect teeth. All from holotype, Tanzania, Nguru Mts, on the ridge S of Kwamanga Village above Mhonda mission nr Turiani, Pócs & Mabberley 6398/A, EGR. Scale bars: A, 50 µm; B-D, 20 µm; E, 0.5 mm.