Fissidens arboricola Brugg.

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 : 14

Fissidens arboricola Brugg. -Nann.

( Fig. 3 )

Fissidens arboricola is characterized by mammillose laminal cells, limbidia restricted to the upper leaves of perichaetial stems, costa evanescent (excurrent in some perichaetial leaves), spores large, 23.5-32.5 µm diam., peristomes anomalous, deeply to completely divided, with “spiral” filaments. Grows in mats and between mosses and liverworts on the bark of small trees and twigs.

Peristome

When moistened the teeth more or less straighten, teeth deeply to completely divided, undivided part 0-3 cells tall, filaments “spiral”, teeth 140-190 µm long and tooth base 28-40 µm wide.

Ornamentation

OPL of both the undivided part and the bifurcation with distinct smooth trabeculae, lamellae smooth or ± smooth (difficult to ascertain because of the through shining IPL; in completely divided teeth lamellae with delicate oblique ornamentation), in mid and distal parts ornamentation of high oblique ridges; IPL trabeculae well developed, lamellae of undivided part with close, horizontal to oblique ridges “hemispiral”, filaments “spiral”.

Sporophyte

Seta ± 1 mm long, almost smooth; capsule narrowly cylindrical, 0.8-1.1 × 0.3 mm, exothecial cells columns ±32, cells oblong with thickened vertical walls; operculum rostrate, 0.25 mm long; spores large, 23.5-32.5 diam., papillose.

Description and illustration

Bruggeman-Nannenga (in press: 38; fig. 1).

Figures

FIG. 3. — Fissidens arboricola Brugg.-Nann. A, B, deeply divided peristome teeth; C, D, completely divided peristome teeth. A, OPL, in the background spiral filaments; B, IPL of two teeth with high, close horizontal to oblique ridges (“spiral”); C, OPL, the trabeculae are recognizable as thin lines, lamellar ornamentation of close oblique ridges; D, IPL basal and mid part with high, close oblique ridges. A, B from Madagascar, Toamasina, Analamazotra Forest Station, Brinda 12240 (type MO, L); C, D from Madagascar, Tulear, Forêt d’Analamaro, ALR-237, private herbarium Bruggeman-Nannenga. Scale bar: 20 µm.