Lejeunea perichymidia M.A.M.Renner, 2021

Renner, M. A., de, Lange P. J. & Glenny, D. S., 2021, A synopsis of Aotearoa / New Zealand Lejeunea (Lejeuneaceae: Jungermanniopsida) and new species in the Lejeunea epiphylla Colenso complex, Arctoa 30 (2), pp. 187-212 : 203-205

13. Lejeunea perichymidia M.A.M.Renner sp. nov.

Fig. 8.

Diagnosis: Lejeunea perichymidia is distinguished by its rotund underleaves with a broad sinus with obtuse to rounded vertex; the ovate leaf-lobes whose apex is rounded; the smooth leaf cell surfaces; the lobules with a keel deeply and nearly continuously curved through 90°, with the lobe-lobule junction situated in a shallow notch, with a first lobule tooth always composed of a single-cell; gynoecia borne on normal leafy shoots, and subtended by a single subfloral innovation of similar stature that continues vegetative growth; and the pentacarinate perianths with a short stipe.

Type: New Zealand, North Island, Auckland Ecological Region, Waitakere Ecological District , Waitakere Ranges , Spraggs Bush , 29.VII.1973, R. E . Beever & J. E . Beever s.n. (holo: AK291280 )

Fig. 8. Lejeunea perichymidia . A: Shoot in ventral view. B: Two transverse stem sections. C: Shoot in dorsal view. D: Lobule pair and underleaf comprising a single module, with underleaf partially cut away. E: Dorsal stem surface showing leaf insertion lines, with dorsal stem midline indicated. F: A single lobule. G: A gynoecium bearing shoot showing normal leafy subfloral innovation. H: Gynoecial bracts and bracteole. I: Perianth transverse sections, smaller to same scale as G. J: Underleaf base. A, C, D, J from CHR556174, others from AK291280.

= Lejeunea epiphylla Colenso Trans. & Proc. New Zealand Instit. 21: 73. 1889 nom illeg. non Mitten J. Proc. Linn. Soc., Bot. 5: 118. 1861 pro parte.

Original material: Hab. Epiphytical on Hymenophyllum (sps.), woods, Dannevirke, County of Waipawa; 1888, W. C.

Description: Plants yellow brown in herbarium forming untidy mostly pure patches. Medium sized for genus, shoots up to 25 mm long, 1.2–1.4 mm wide, shoots monomorphic, sparingly branched. Stems 250–285 µm diameter, with 7 cortical cell rows and around 13 smaller medullar cell rows, cortical cell walls evenly thickened, medullar cell walls thin, all unpigmented. Lobes ovate, 326–748 (507 ± 94) µm long by 308–878 (544 ± 104) µm wide, imbricate, not falcate, not obliquely spreading, slightly concave, outer margin slightly downrolled. Lobe margins entire, lobe dorsal surface pseudopapillate by virtue of cell bulge. Lobules 326–748 (507 ± 94) µm long by 326–748 (507 ± 94) µm wide, 0.125–0.2 lobe area, naviculiform, carinal region broadly inflated, narrowing and turning with keel toward shoot apex at outer end, keel half lobe width. Antical lobule margin inrolled and hidden along the inner two thirds, less or not inrolled along the outer third so that the primary and secondary teeth are visible in ventral view, keel half width of lobe. Lobule primary tooth single celled, prominent, pointing toward shoot apex, fused with surrounding cells along 1.5 sides, rounded, papilla at base, slightly entally displaced. Lobule margin between primary tooth and lobe-lobule junction forming a bridge over the opening into carinal region which is perpendicular to shoot axis and fused seamlessly with the lobe margin, but for a shallow depression in the lobe surface behind this margin. Lobule secondary tooth obtuse to rounded, usually of a single reniform cell, occasionally two cells, not exceeding the primary tooth except in robust lobules. Lobules dimorphic, reduced lobules 12–16 cells, with prominent apical tooth. Underleaves 326–748 (507 ± 94) µm long by 326–748 (507 ± 94) µm wide, rotund, broadest at midpoint, bifid 0.25–0.33, sinus 326–748 (507 ± 94) µm deep, U-shaped, lobes not divergent, apices obtuse. Attached to 2–3 stem cortical cells, insertion shallowly arched, underleaves scalloped at base, lateral basal cells not markedly inflated. Underleaves equally spaced, remote to contiguous on robust shoots. Oil-bodies numerous, small, fusiform, hyaline, smooth, arranged in a submarginal ring. Asexual reproduction absent.

Paroicous. Gynoecia produced sporadically on normal leafy shoots, subtended by a single lejeuneoid subfloral innovation that continues vegetative growth. Female bracts united to bract underleaf on both sides, the whole bract gyre flexed and reflexed, forming a cradle around the archegonium. Perianths obovate, around 1500 µm long overall, with free perianth c. 1400 µm long, equally 5–carinate, carinae ridged, and extending approximately half way down the perianth sides; rostrum distinct; with short stipe at base c. 150 µm long of two or three tiers of elongated cells.