Cheilolejeunea aracaensis C.J. Bastos, A.M. Sierra & C.E. Zartman, 2016

Bastos, Cid José Passos, Sierra, Adriel M. & Zartman, Charles E., 2016, Three new species of Cheilolejeunea (Spruce) Steph. (Marchantiophyta, Lejeuneaceae) from northern Brazil, Phytotaxa 277 (1), pp. 36-46 : 37-38

Cheilolejeunea aracaensis C.J. Bastos, A.M. Sierra & C.E. Zartman , sp. nov. ( Figs. 1‒10 , 35, 36, 38, 40 )

The new species is characterized by its elongate, weakly falcate second and first lobule teeth, the first tooth partially overlapping the second tooth; gynoecial innovations absent; perianth 4-keeled, lateral keels flat, crenulate, and rostrum short.

Type :— BRAZIL: Amazonas , Barcelos, Serra Aracá, elev. 690 m, growing on a rocky seep, 23 Aug. 2014, C. Zartman 9686 (holotype ALCB; isotype INPA) .

Plant small, 540–610 μm wide, branching Lejeunea - type. Stem 50 μm in diameter, in transverse section with 7 cortical and 3–4 medullary cells. Ventral merophyte two cells wide. Leaves widely spreading from stem, contiguous to slightly imbricate; lobe ovate, slightly falcate, weakly convex, 230–350 μm long × 170–200 μm wide, dorsal margin arched, strongly crenulate, ventral margin straight, crenulate, apex acute, mostly curved; lobe cells oblong, 23–35 μm long × 18–20 μm wide, thick walled, papillose dorsally, trigones large, intermediate thickenings scarce; oil bodies not observed; ocelli absent; lobule ovate, inflate, 100–150 μm long × 80–90 μm wide, free margin invlute, second tooth elongate, weakly falcate, first tooth elongate, weakly falcate, partially overlapping the second tooth, hyaline papilla on the inside base of the first tooth, keel arched, strongly papillose. Underleaves small, 120–180 μm long × 110–170 μm wide, distant, bifid to 1/2–1/3 its length, sinus acute to lunulate, base cuneate, insertion line curved. Autoicous. Androecia intercalary, 3–4 pairs, bracts imbricate. Gynoecia terminal or on lateral branches, without gynoecial innovation; bract lobe obovate, 550 μm long × 330 μm wide, margin crenulate, lobule obovate, 330 μm long × 110 μm wide; bracteole widely obovate, bifid; perianth obovate, 720 μm long × 390 μm wide, 4-keeled, lateral keels flat, crenulate, rostrum short, 2‒3 cells long. Vegetative propagation not observed.

Additional material examined:― VENEZUELA: Estado Bolivar, Cerro Guaiaquinima, near NE edge of upper plateau (near camp 2), 5°54’N, 63°27’W, 1100 m, mossy Forest in narrow valley, 9 Feb. 1990, H. Sipman 26918 ( VEN).

Etymology: In reference to the type locality.

Ecology and distribution: Cheilolejeunea aracaensis presently known from its type locality on the Serra Aracá in northern Brazil at the Southern flanks of the Guyana highlands and from Cerro Guaiaquininma, Venezuela. The holotype was collected from dense mats on a rocky seep, together with an unidentified Odontoschisma ( Dumortier 1831: 68) Dumortier (1835: 19) .

Figures

FIGURES 1‒10. Cheilolejeunea aracaensis. 1. Gametophyte, ventral view. 2‒3. Portion of gametophyte, ventral view. 4. Underleaf and lobule. 5‒6. Leaf lobules apices. 7. Laminal cells. 8: Stem in cross section. 9. Gynoecial branch with perianth, ventral view. 10:Androecial branch, ventral view (from holotype, C. Zartman 9686).

FIGURES 35‒41. Comparison between C. aracaensis and C. asperiflora. 35‒36. Apical teeth lobue of C. aracaensis. 37. Apical teeth lobule of C. asperiflora. 38. Part of gametophyte with underleaves of C. aracaensis. 39. Part of gametophyte with underleaves of C. asperiflora. 40. Perianth of C. aracaensis. 41. Perianth of C. asperiflora (C. asperiflora: photo from type specimen - NY).