Monographs Details: Neurolejeunea sastreana Gradst.
Authority: Gradstein, S. Robbert. 1994. Lejeuneaceae: Ptychantheae, Brachiolejeuneae. Fl. Neotrop. Monogr. 62: 216. (Published by NYBG Press)
Family:Lejeuneaceae
Synonyms:Lejeunea breutelii var. regularis (Gottsche) Hampe
Description:Species Description - Dioicous (male and female plants growing mixed). Plants 1-2 cm long × 0.6-1 mm wide, blackish brown. Stems ca. 0.1 mm in diam., in cross section composed of ca. 16 epidermal cells surrounding 20 medullary cells; ventral merophyte four cell rows wide. Leaves contiguous to subimbricate, diverging from the stem at an angle of ca. 90°, falcate, dorsal lobe asymmetrically ovate, 0.45-0.6 × 0.3-0.45 mm, apex rounded, plane, ventral margin curved, forming an angle of 90°-145° with the keel; oil bodies (seen in the type material) 2-4 per cell, globose to bluntly ellipsoid, 5-8 × 4-5 m, colorless, almost homogeneous, the surface smooth or faintly papillose by a few coarse, protruding globules. Lobules flaskshaped, up to l/2× leaf length, rarely reduced, not flattened, keel arched especially near base, forming an angle of 45°-60° with the axis, rounded, smooth or roughened by slightly mamillose cells, free margin involuted, margin cells colorless, apical tooth incurved, invisible in optical view, broad triangular, 3 cells long and 3-4 cells wide at base, fragile, in part made up of colorless, thin-walled cells, first tooth large, "papilla-like," protruding from the apex and directing backwards, consisting of an elongated, 25-40 µm long, apically strongly thickened (12-20 µm thick) cell. Underleaves distant, ca. 0.2-0.25 mm long, 0.25-0.3 mm wide, 2-3× stem width, insertion line straight. Androecia on short-specialized branches, bracts in 3-5 series, underleaves limited to the base of the spike. Gynoecia with 1-2 sterile innovations, bract lobules oblong, hardly elongated beyond the keel, apex of lobules rounded, keel without wing; bracteoles obovate-oblong, 0.6 × 0.4 mm, apex rounded, margins plane. Perianths as in Neurolejeunea breutelii, lateral auricles well-developed (ca. 0,3 mm long), ventral keel with two folds, not horn-like expanded.

Discussion:Neurolejeunea sastreana has in the past been confused with N. breutelii, from which it is immediately recognized by the large, thick-walled, papilla-like cell (= first tooth) protruding from the apex of the lobule. The two species are no doubt closely related as is indicated by the occasional presence of a rudimentary papilla (up to 10 ┬Ám long) in N. breutelii. The ranges of the two species overlap in the West Indies but N. sastreana apparently has a much more restricted distribution. In Puerto Rico, for instance, N. sastreana has only been collected in the wet, eastern portion of the island (Luquillo Mts.), whereas N. breutelii occurs throughout the island.
Distribution:Dominican Republic South America| Puerto Rico South America| Martinique South America| Venezuela South America| Aragua Venezuela South America| Miranda Venezuela South America|