Fissidens gardneri Mitt.

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 : 19-20

Fissidens gardneri Mitt.

( Fig. 7 )

This tiny species is characterized by open to almost open vaginant laminae, pluripapillose cells, the mostly obtuse leaf apex, costae ending far below the leaf apex and in the upper part often covered by laminal cells, limbidia restricted to the vaginant laminae of the upper leaves of perichaetial plants, undivided to irregularly divided, straight papillose peristome teeth and large spores. Scattered on bark of trees often not mixed with other mosses.

Peristome

± straight when dry, ± straight when wet, stiff, divided, irregularly divided or undivided, basal undivided part 3-4 cells tall, teeth 100-145 µm long, tooth base 25.5- 32 µm wide.

Ornamentation

OPL basal 2-4 cells with high, smooth, thin trabeculae and smooth to papillose lamellae, thickness and transparency of basal OPL variable (compare Fig. 7A, E ); IPL basal 3-4 cells with high, papillose trabeculae and smooth (or papillose?) lamellae; IPL lamellae incrassate ( Fig.7C ) with densely papillose surface ( Fig. 7D ); mid and distal part of both OPL and IPL papillose.

Sporophyte

Seta 1-1.5 mm long, smooth; capsule cylindrical, 0.45- 0.55 × 0.25-0.3 mm, exothecial cell columns ± 32, of the cells oblong exothecial cells; operculum 0.25 mm long; spores subglobose to ellipsoid, large, 20-37 µm, thick-walled, coarsely papillose, occasionally germinating in the capsule.

Description and illustration

Pursell (2007: fig. 76L).

Figures

FIG. 7. — Fissidens gardneri Mitt. A, OPL of undivided part of two teeth (left one broken off); B, side view of tooth; C, IPL lamellae with focus below the papillose surface to show the incrassate platelets; D, as C with focus on the papillose outer surface; E-H, same tooth at different levels; E, undivided part and bifurcation, or rather trifurcation with focus on the transparent OPL,the underlaying IPL is clearly visible;F, photo E with OPL cells outlined to show the single column of OPL cells; G, focus on IPL; H, photo G with IPL cells outlined to show the two columns with the zigzag border line. A-D from Tanzania,WSW of Morogoro town, Pócs 87041/R, EGR, private herbarium Bruggeman-Nannenga; E-H from Madagascar, Fianarantsoa, Magill & Crosby 12919, MO. Scale bars: 20 µm.