Cephalocarpus pyramidalis S. M. Costa 2024, sp. nov.

4. Cephalocarpus pyramidalis S.M.Costa, sp. nov. (Figures 1D, 2D, 3D) Similar to Cephalocarpus confertus, but it has bigger leaves (leaf blades ~ 15 × ~ 0.5 cm, versus (3)6–10 × 0.2–0.25 cm in C. confertus), the fruit with a triangular beak without a constriction zone between the main body and the beak (the achene is conical to short cylindrical and with the constriction zone in C. confertus) Type specimen:— VENEZUELA. Bolivar: Chimantá Massif, among southwest-facing sandstone bluffs of Chimantá-tepuí (Torono-tepui) (near Southern corner), 1700 m, 19–20 May 1953, J.A. Steyermark 75480 (NY! – holotype, F! - isotype) Monoecious herb: sexes intermingled. Caudex 5–12 mm diam. including sheaths remains and adventitious roots. Leaf: sheath glabrous, reddish-brown after dry; blade ~15 × ~ 0.5 cm, linear-lanceolate, “V”-shaped and flattened, sparsely minute ciliate or glabrous except for the blade base margins sparsely minute ciliate, concolorous, reddish brown. Inflorescence head-like (appearing sessile), single at each prophyll; culm <1 cm, compressed, margins ciliate. Involucral bract (lowermost) leaf-like: sheath – 1.3 mm long, glabrous, reddish-brown after dry; blade –6 × – 1.1 mm, “V” in cross section, margin sparsely and minute ciliate, reddish-brown after dry. Male spikelet ~6 × ~ 1mm, 5–6 glumes, 1 flower; glume (outermost) ~ 3.2 mm long, glabrous, mucronate (mucron ~ 1.2 mm long); stamens 3,connective projection short conical and glabrous. Female spikelet ~4.5 × ~ 1.2 mm, 5–6 glumes, 1 flower; glume (outermost) ~ 3 mm long, glabrous, mucronate (mucron 1 mm long); stigmas not observed. Fruit ~3.2 × ~ 1.1 mm, ellipsoid-hexagonal, smooth, ciliate at the apex, main body continuous to the beak; hypogynous scales ~ 3 mm, lanceolate, trichomes up to 1.7 mm long; beak ~ 0.85 mm long, triangular, pubescent. Etymology:—The epithet refers to the pyramidal form of the fruit beak. Distribution:—Known only from the type locality. Taxonomic notes:—This intriguing species resembles an oversized Cephalocarpus confertus Gilly (1942: 293- 294) in its vegetative morphology. But additionally to its clearly bigger size, the fruit characters are notably different, lacking the constriction zone between the body and the beak, with lanceolate hypogynous scales and a pyramidal beak. It is only registered for the type-locality and by a single collection.