Nasa angeldiazioides T.Henning, R.H. Acuna , E.Rodr., L. Garcia-Llatas & Weigend, 2019

Henning, Tilo, Acuna Castillo, Rafael, Rodriguez Rodriguez, Eric Frank, Garcia Llatas, Luis Felipe & Weigend, Maximilian, 2019, A new striking and critically endangered species of Nasa (Loasaceae, Cornales) from North Peru, PhytoKeys 121, pp. 13-28 : 13

Nasa angeldiazioides T.Henning, R.H. Acuna, E.Rodr., L. Garcia-Llatas & Weigend sp. nov. Figs 2 A–E , 3

Type.

Peru: Dept. Lambayeque, Provincia Ferreñafe, Distrito Incahuasi, "Refugio de Vida Silvestre Laquipampa", ruta Piedra Parada, April 2015, L. F. García Llatas 333 (Holotype: HUT, Isotypes: HUT)

Diagnosis.

Nasa angeldiazioides is similar to N. bicornuta , N. pteridophylla and N. urens but differs in having strongly amplexicaul leaves, sessile to amplexicaul prophylls on the pedicels and flowers with white petals and dark red nectar scales. The unique interrupted bipinnatisect leaves with rounded leaflet apices distinguish N. angeldiazioides from all other taxa of Nasa and Loasaceae as a whole.

Description.

Annual herb 30-50 (-110) cm tall. Stem subterete to weakly grooved, 3-9 mm thick at base, pale green with dispersed darker green streaks and dots and whitish protuberances; set with scattered yellowish setae 1-1.5 mm long and covered with medifixed t-shaped hairs, 0.1-0.3 mm. Adventitious roots present in the L-shaped stem base. Leaves alternate, petiolate below (petiole to 10-15 mm), amplexicaul above sometimes with decurrent base, sessile in between; glabrescent; lamina oblong to widely rhomboidal in outline, (80-) 150-280 (-310) mm long and (25-) 60-220 (-280) mm wide (the petiolate leaves smaller than the sessile ones), pinnate at the base and apex, bipinnatisect in the central part, dissected nearly to midvein, central pinnae subpinnatisect, lobules narrowly-oblong; apex acuminate; abaxial surface covered with short, prostrate, yellowish glochidiate hairs, 0.05-0.1 mm and scabrid hairs 0.2-0.3(-0.5) mm along the veins; adaxial surface covered with few scabrid hairs 0.2-0.3 mm long (never on the veins), venation pinnate. Inflorescences of 2-5 terminal or axillary monochasial branches each 10-20 cm long, with (3-) 5-10 (-15) pendent flowers per branch. Flowers borne opposite to an amplexicaul upper leaf, bracts sometimes recaulescent, simple, ovate, margin dentate, sessile, (10-) 15-30 (-33) long and (6-) 10-17 (-25) mm wide, pedicel often provided with a single, ovate, sessile to amplexicaul prophyll, (15-) 20-25 mm long and 12-15 mm wide. Flowers pentamerous, pedicels 30-50 mm, green at the upper half, basally brownish, appearing dessicated, calyx covered densely with scabrid hairs (0.5-0.7 mm) and sparse glochidiate hairs (0.1-0.2 mm), tube conical, 4 × 3 mm, calyx lobes ovate acuminate, 7 × 4 mm, densely covered with scabrid hairs on back. Petals spreading to slightly reflexed, white, deeply cymbiform, cucullate, 15-23 mm long, 5 mm wide and 9-10 mm deep, base green, unguiculate and abruptly widened into two small triangular teeth 2 mm from base, these bent towards the centre of the petal, almost touching each other and leaving only a narrow gap for the stamens, adaxial surface set with scattered scabrid (0.2-0.3 mm) and uniseriate short glandular (3-7 cells) (0.3-0.7 mm) hairs; abaxial surface set with scattered glochidiate (0.1-0.2 mm) and uniseriate short glandular (3-7 cells) (0.3-0.7 mm) hairs. Nectar scales dark red at the base (sacs), white towards the neck and wings, with triangular back, much narrowed above, 7-8 × 4 mm, base incurved, back with two conspicuous, globose nectar sacs about 2 mm in diameter, scale back with 4-5 transversal calli, neck thickened and slightly recurved, laterally protracted into two small erect wings 1 mm long and 0.5 mm wide. Staminodia 9-10 mm long, base slightly dilate, filiform above, papillose, yellowish. Stamens in epipetalous fascicles of 12-15 each, filaments 8-10 mm, white, anthers 0.3 mm long and wide, yellow. Ovary inferior, with three parietal placentae and numerous ovules. Fruit a capsule, horizontal to semi-erect due to the sigmoid pedicel that elongates postflorally, capsule narrowly clavate, slightly curved, purplish, opening with 3 apical valves.

Figures

Figure 2. Morphology of Nasa angeldiazioides (A-E, L, M) and similar taxa (F-K). A Flower, frontal view B Flower, lateral view C Capsule, lateral view, note the thin, curved pedicel D General habit of several flowering plants in their natural habitat, Bosque de Chinama E Mature basal leaf F Mature leaf of Nasa urens G Young plant of N. pteridophylla H Flower of Nasa formosissima, lateral view I Amplexicaul bract of N. formosissima J, K Leaves of Angeldiazia weigendii, abaxial surface, note the overall shape and the ampexicaul leafbase visible in the background L Bract, prophyll and capsules of Nasa angeldiazioides M Lowermost bract of N. angeldiazioides, outlined from a specimen photograph. (Credits: photographs A, B, D B. Esquerre-Ibanez J, K Mario Zapata).

Figure 3. Nasa angeldiazioides. A Flowering shoot B Mature leaf C Flower D Petal E Calyx lobe F Nectar scale, abaxial view G Staminode, lateral view H Capsule, lateral view. Drawing prepared by L. Garcia (D-H), T. Henning (A, B) and R. Acuna (C).