Fissidens diaphanodontus (P. de la Varde) Bizot

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 : 14-19

Fissidens diaphanodontus (P. de la Varde) Bizot

( Fig. 6 )

Fissidens diaphanodontus is characterized by oblong-lanceolate leaves with broadly acute to rounded, obtuse often apiculate apex, conicomammillose laminal cells, limbidia limited to the upper leaves of perichaetial stems and short costae ending 2-11 cells below the apex. Growing between mosses and liverworts on bark of trees.

Peristome

Straightening when moistened, erect to slightly curved inwards, stiff, undivided, up to 100 µm long. This characteristic peristome is easily recognized by its unique fenestrate appearance.

Ornamentation

OPL with basal five or six cells fenestrate with strongly papillose trabeculae and vertical walls surrounding the smooth lamellae,

more distally the trabeculae and vertical walls become indistinct and the lamellae densely papillose or with indistinct oblique ridges; basal six to nine IPL cells like the basal OPL cells but more coarsely papillose, distal part densely papillose. OPL and IPL thin, IPL slightly thinner than the OPL ( Fig. 6F ).

Sporophyte

Seta 1.4 mm long, ± smooth; capsule cylindrical, 0.5- 0.55 × 0.2 mm with exothecial cell columns ± 32, the cells oblong with thickened vertical walls, operculum not observed, spores 13.5-17.5 × 12.0-16.0 µm, papillose.

Description and illustration

Bruggeman-Nannenga & Berendsen (1990: fig. 5b); Potier de la Varde (1951: fig. 2).

Figures

FIG. 6. — Fissidens diaphanodontus(P.de la Varde) Bizot. A-C, OPL;C, SEM photograph;D, E, IPL; D, with OPL in foreground; E1, distal filaments; E2, basal cells; F, side view of tooth; G, moist capsule with erect peristome teeth. A, B, G from Guinea, Nzérékoré Region, Macenta Prefecture, Lisowski 100, private herbarium Bruggeman-Nannenga,KRAM;C from Inoue,Bryoph.Sel.Exsic.580,L; D-F from Tanzania,Pócs 6387/Q, PC;C previously published in Bruggeman-Nannenga & Berendsen1990. Scale bars: A, D-F, 20 µm; B, 25 µm; C, 10 µm; E1-2, 20 µm; G, 0.5 mm.