Justicia rojasiae R. Villanueva & J. R. I. Wood, 2025

Villanueva-Espinoza, Rosa, Deng, Yunfei, Scotland, Robert & Wood, John R. I., 2025, Preliminary notes on Justicia (Acanthaceae) in Peru, PhytoKeys 258, pp. 1-123 : 1-123

4. Justicia rojasiae R. Villanueva & J. R. I. Wood sp. nov.

Type.

Peru • Pasco, Prov. Oxapampa, Dist. Oxapampa, Parque Nacional Yanachaga-Chemillén. Quebrada Yanachaga , 10°24'S, 75°28'W, 2250 m, 14 June 2003, R. Vásquez 28272 (holotype MO-7066511 , isotypes HOXA, US, USM) .

Diagnosis.

Similar to Justicia cuspidulata in the 4 - lobed calyx, red corolla and spicate inflorescence with flowers in opposite pairs and reduced bracts resembling the bracteoles, but leaves narrowly oblong-ovate, 2–3 times as long as broad (not ovate-elliptic, scarcely longer than broad), petioles 2–4 mm (not mostly> 10 mm), inflorescence long-pedunculate, lower flower pairs distant, corolla lips relatively short (3–5 mm long, not 10 mm), calyx lobes c. 9 mm long (not 7–8 mm); it also resembles J. alpina but the leaves are narrowly oblong-ovate, 2–3 times as long as broad, (not ovate, scarcely longer than broad), distinctly petiolate (not subsessile) and spikes much shorter, 4–5 cm long (not 6–20 cm).

Description.

Perennial herb reaching at least 50 cm in height; stem obscurely 4 - angled, subglabrous to obscurely bifariously scurfy-puberulent. Leaves shortly petiolate, lamina mostly 4–7 × 1.3–2 cm, narrowly oblong-ovate, apex acuminate to an obtuse apex, base cuneate, slightly oblique, both surfaces glabrous and lacking prominent cystoliths, veins 4–5 pairs; petioles 2–4 mm, glabrous. Inflorescence of lax terminal spikes, 4–5 cm long, the flowers sessile, solitary or paired, opposite along the rhachis, up to 1.5 cm distant; peduncles 1.5–3.5 cm long, bifariously pubescent; rhachis glandular-pubescent; bracts linear 3–4 × 1 mm, glabrous or thinly (glandular-) pubescent; bracteoles 4–5 × 0.5 mm, linear, sparsely pubescent; calyx 4 - lobed to base, lobes 9–10 × 0.5 mm at anthesis, linear, acuminate, sparsely pubescent with multicellular, sometimes gland-tipped hairs; corolla pink, pubescent on the exterior, 2.5 cm long; tube gradually widened from 1 mm at base to 5 mm at mouth, 2 - lipped, upper lip c. 1.5–3 mm long, notched, lower lip very shallowly lobed, lobes c. 3 mm long, ovate, rounded; filaments glabrous, white, anther thecae broadly oblong, 1.25 × 1 mm, held at same height, glabrous, lacking appendages; pollen prolate, 39–43 × 23–24 μm, 2 - aperturate, colporate, one row of c. 9–12 insulae and a second row of peninsulae on either side of aperture (Fig. 48 B ); ovary and style glabrous. Capsule and seeds not seen.

Illustration.

Figs 5 , 6 A, B .

Etymology.

This species is named after Rocio Rojas who has contributed to our knowledge of Peru’s flora by numerous records, many cited in this paper.

Phenology.

Flowers from April to June.

Habitat.

Forest and forest relics, 1900–2250 m.

Distribution.

Endemic to the area around the Yanachaga-Chemillén National Park in Oxapampa Province, Pasco Department. Fig. 54 .

Material examined.

Peru • Pasco: Prov. Oxapampa, Dist. Chontabamba, Ecolodge Ulcumano 10°38'08"S, 75°25'37"W, 2244 m, 10 May 2021, R. Vásquez et al. 45620 ( HOXA, USM) ; • ibid. La Suiza Vieja , 10°38'47"S, 75°30'20"W, 2050 m, 18 June 2004, R. Rojas et al. 2936 ( HOXA, MO) ; • ibid., 10°38'34"S, 75°27'31"W, 2000–2200 m, 23 June 2004, R. Rojas et al. 3055 ( HOXA, MO) ; • ibid., 10°38'S, 75°40'W, 1900 m, 16 April 2010, R. Vásquez et al. 36460 ( HOXA, MOL, MO, US, USM) ; • ibid., Dist. Oxapampa, P. N. Yanachaga-Chemillén , the type .

Note.

R. Rojas et al. 1174 ( MO) from Oxapampa, Dist. Pozuzo, Puesto de Control, Huampal (10°11'S, 75°34'W) at 1100 m appears somewhat similar but has a much denser inflorescence.

Figures

Figure 5. Justicia rojasiae A habit B detail of stem C detail of adaxial leaf surface D bract E bracteole F calyx G corolla opened out H anther J ovary. Drawn from Vásquez 28272 by Margaret Tebbs

Figure 6. Photographs of A, B Justicia rojasiae (Vásquez 36460). Note the indumentum and absence of “ herring bone ” patterning. C, D Justicia pozuzoensis (Villanueva 925). Note the alternate flowers. A, B Rodolfo Vásquez, C, D Rosa Villanueva.

Figure 48. Pollen images A Justicia alpina subsp. machupicchuensis (Stafford 1222) B J. rojasiae (Vásquez et al. 28272) C J. pozuzoensis (Villanueva 925) D J. oppositiflora (Smith & Pretel 4189) E J. discolor subsp. discolor (Woytkowski 5824) F J. discolor subsp. filisepala (Beltrán 5429). Scale bars: 10 μm.

Figure 54. Distribution of Justicia cuspidulata (yellow polygon), J. discolor subsp. discolor (orange circles), J. discolor subsp. filisepala (red squares) and J. rojasiae (green triangles) in Peru.