Brayopsis limensis Al-Shehbaz

Al-Shehbaz, Ihsan A., Cano, Asunción, Trinidad, Huber, Gonzáles, Paúl & Huamán, Elluz, 2018, Two new Peruvian species of Brayopsis (Brassicaceae; Cruciferae), and a key to the species, Phytotaxa 383 (1), pp. 111-111 : 111

Brayopsis limensis Al-Shehbaz , Trinidad, A. Cano & P. Gonzáles, sp. nov.

Diagnosis:— Brayopsis limensis is easily distinguished from the other species of the genus by being densely pulvinate and having glabrous fruit and leaves adaxially with trichome 1.2 − 2.1 mm long.

Type: — PERU. Lima: Prov. Oyón, Abra Macaulo, arriba de laguna Surasaca , 10°31 ʹ 07 ʺ− 10°31 ʹ 10 ʺ S, 76°48 ʹ 23 ʺ− 76°48 ʹ 03 ʺ W ( UTM: 302312 − 302909, 8836191 − 8836095, zone 18), 4750 − 4800 m, 3 December 2017, A. Cano, H. Trinidad, P. Gonzáles & S. Riva 22620 (holotype, USM-304585; isotype, MO-6835842). Figures 1 , 2 .

Description: —Herbs perennial, densely pulvinate; caudex woody, much branched, covered with petioles of previous years. Basal leaves densely rosulate; petiole persistent for many years, 3 − 7 mm long, not ciliate, indurate and becoming stramineous with age, ca. 1 mm wide at base, subequal to slightly longer and distinctly thicker than blade; blade narrowly ovate to oblanceolate, 3 − 5 × 1.2 − 2 mm, glabrous abaxially, sparsely to densely pubescent adaxially with straight or rarely slightly crisped trichomes (1.2 −) 1.5 − 2.1 mm long and as long as or longer than blade width, margin entire, apex obtuse. Fruiting pedicels 6 − 10(− 13) mm long, solitary from basal rosette, thick, glabrous. Sepals ovate, erect, 2 − 2.5 mm long, purplish, glabrous, caducous; petals white, oblanceolate, 2.5 − 3 × 1 − 1.5 mm, caducous, undifferentiated into blade and claw, apex obtuse; filaments 2 − 2.3 mm long, caducous; anthers ovate, 0.5 − 0.6 mm long; ovules 12 − 14 per ovary. Fruit linear, terete, straight, 6 − 10 × 1 − 1.2 mm; valves glabrous, midvein distinct; septum complete; gynophore obsolete; style 0.2 − 0.7 mm long. Seeds oblong, 0.8 − 1.2 × 0.5 − 0.6 mm.

Phenology: —Flowering in December and fruiting in March to July.

Habitat: — Brayopsis limensis grows on crioturbed soil of rocky slopes at elevations of 4100 − 4800 m.

Etymology: —The species epithet limensis is named after the Peruvian department Lima.

Distribution: —Endemic to Peru and known from Ancash, Lima, and Apurímac departments.

Discussion: — Brayopsis limensis is closely related to the Peruvian-endemic B. chacasensis Al-Shehbaz & A. Cano , a narrow endemic known thus far only from the type gathering from Depto. Ancash, as well as to B. calycina (Desv.) Gilg & Muschl. , the most widespread species in the genus where it grows in Argentina (Catamarca, Salta, Tucumán), Bolivia (La Paz, Potosí, Tarija), and Peru (Ancash, Arequipa, Ayacucho, Cajamarca, Cuzco, Huancavelica, Huancayo, Lima, Moquegua, Puno, Tacna). It resembles B. chacasensis in being densely pulvinate with indurated and persistent petioles, smaller flowers, fruit, and seed of about the same size, short fruiting pedicels hardly exceeding 1 cm in length, and the number of ovules per ovary. From this species, the novelty differs by having leaf blades densely pubescent adaxially with trichomes (1.2 −) 1.5 − 2.1 mm long and as long or longer than blade width, caducous floral parts that fall off shortly after anthesis, complete septum, and non-ciliate petioles. By contrast, B. chacasensis has glabrous leaf blade terminated with 1 or 2 trichomes, persistent floral parts that remain until fruit dehiscence, perforated septum, and ciliate petioles. From B. calycina , B. limensis differs by being densely pulvinate (vs. not pulvinate) with shorter fruiting pedicels 0.6 − 1(− 1.3) (vs. (1.5 −)2 − 4.2(− 5.5) cm long, fewer (12 − 14 vs. (16 −)20 − 36) ovules per ovary, smaller seeds (0.8 − 0.9 × ca. 0.5 vs. 1.1 − 1.4(− 1.7) × 0.7 − 0.9 mm), and leaves adaxially pubescent with usually straight trichomes (1.2 −) 1.5 − 2.1 mm long (vs. glabrous or sparsely pubescent with crisped trichomes to 1 mm long.

Additional specimens examined (paratypes): — PERU. Ancash: Prov. Huari, Huascaran National Park, 3 − 4 km below Cahuish tunnel, 77°14 ′ W, 9°41 ′ S, 10 July 1985, Smith & Buddensiek 11116 (MO). Apurimac: Cotabambas, Challhuahuaco, Cerro Ccomerqaqa, 76°51 ʹ 46 ʺ− 76°49 ʹ 31 ʺ W, 4100 − 4150 m, 3 March 2013, Cano & Valencia 21455 (MO, USM). Lima: Oyón, Abra Macaulo, arriba de laguna Surasaca, 4750 − 4800 m, 10°31 ʹ 07 ʺ− 10°31 ʹ 10 ʺ S, 76°48 ʹ 23 ʺ− 76°48 ʹ 03 ʺ W, December 2017, Cano et al. 22622 (MO, USM).

Figures

FIGURE 1. Brayopsis limensis A. Part of cushion. B. Leaf. C. Petal. D. Fruit. E. Seed. Drawn by Al-Shehbaz: A−C from isotype (MO- 6835842); D, E from paratype Smith & Buddensiek 11116 (MO).

FIGURE 2. Brayopsis limensis A. Small cushion. B. Close-up of leaves and flowers. Scale bars: A = 5 mm; B = 2 mm. Photo by Huber Trinidad.