Fissidens ezukanmae Brugg.

Bruggeman-Nannenga, Maria A., 2019, Fissidens ezukanmae Brugg. - Nann., sp. nov. (Fissidentaceae, Bryopsida), a new species from termite mounds in Nigeria, Cryptogamie, Bryologie 20 (3), pp. 15-18 : 16

Fissidens ezukanmae Brugg. -Nann., sp. nov.

( Fig. 1 )

DIAGNOSIS. — Species haec Fissidenti pellucido similis sed cellulis mammillatis neque non foliis omnibus elimbatis vel limbidiis ad foliis superioribus plantarum perichaetialium limitatis facillime dignoscenda. TYPE. — Nigeria, Taraba State, Ngel Ngaki, towards the outskirts of Yelwa village, on the Mambilla Plateau, 7°05’07”N, 11°04’11”E, alt. 1600 m, on termite mound, XI 2015, leg. I. Ezukanma 041 (holo-, L; iso-, KRAM; iso-, LUH).

ETYMOLOGY. — The new species is named in honour of its collector Dr Izuchukwu Ezukanma of Lagos, Nigeria.

DESCRIPTION

General description

Plants. Growing in mats.

Stems. 3-4 mm long, 0.7-1.2 mm wide with leaves (perichaetial stems 3´1 mm with 5 leaf pairs), unbranched or branched, often with proliferations from old perichaetia, pinnately foliated with 7-12 leaf pairs, without central strand.

Rhizoids. Brown, smooth.

Axillary nodules. Not differentiated; leaves distant, hardly crispate when dry, lanceolate, less often elliptical, acute, 0.5- 0.9 × 0.1-0.2 mm, 3.0-5.5 times as long as wide, margin denticulate occasionally subentire, most leaves elimbate.

Limbidium. Restricted to the vaginant laminae of upper and mid leaves of perichaetial stems, extending up to ¾ the length of the vaginant laminae, reaching the insertion in perichaetial leaves? (hard to observe), not reaching the insertion in mid leaves, marginal, unistratose, insertion, up to 11 µm wide, consisting of wide cells.

Vaginant laminae. ± ª⁄5 the leaf length, narrower than the stem, unistratose, slightly to almost half open, completely open in some perichaetial leaves.

Dorsal lamina. Mostly ending well above the insertion, not decurrent.

Dorsal and apical lamina. Unistratose

Costa. Percurrent to excurrent, in cross-section bryoides-type.

Mid dorsal laminal cells. 6.0-11.0 × 4.0-7.0(-8.5) µm, 1-2 times as long as wide, mammillose.

Mid vaginant laminal cells. 6.0-12.5 × 3.5-7 µm, 1.5-3.0 times as long as wide, mammillose.

Gemmae. Not observed.

Fertile parts

Perigonia. Not seen.

Archegonia. In terminal perichaetia and also axillary, 200- 250 µm long, solitary and naked in some leaf axils ( Fig. 1C ), at least some of which developing into mature sporophytes;

Perichaetial leaves. 1.5 mm long.

Calyptra. 0.6 mm long.

Sporophyte. Singly per perichaetium.

Setae. 4 mm long, smooth.

Capsule. Erect, 0.7 × 0.35 mm, ± 32 files of quadrate to oblong, thick-walled exothecial cells.

Peristome. Of scariosus - type, with curved, short teeth, 190 µm long, 40-41 µm wide at base.

Operculum. Not seen.

Spores. Subglobose 16-19 µm in diameter, coarsely papillose.

Figures

FIG. 1. — Fissidens ezukanmae Brugg.-Nann., sp. nov.: A, stem with terminal perichaetium;B, branched vegetative stem;C, part of stem with axillary archegonia (upper one left anomalously developed); D-G, leaves; H, basal part of vaginant lamina of subperichaetial leaf with limbidium; I, leaf apex; J, mid leaf; K, insertion of leaf; L, detail mid-vaginant lamina; M, cross-section of stem; N, cross-section of leaf with bryoides-type of costa. All from holotype. Scale bars: A,B, 1 mm; C, 0,5 mm; D, 0,1 mm; E-G, 0,1 mm; H, 50 µm; I, 100 µm; J,K, 50 µm; L, M, 50 µm.