Justicia cuspidulata (Nees) Wassh.

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

2. Justicia cuspidulata (Nees) Wassh. , Monogr. Syst. Bot. Missouri Bot. Gard. 45: 1253. 1993. ( Wasshausen 1993: 1253)

Rhytiglossa cuspidulata Nees , Prodr. [A. P. de Candolle] 11: 348. 1847. ( Nees 1847 b: 348) Type. PERU. Amazonas, Chachapoyas. A. Mathews 3152 bis (holotype K- 000529252, isotypes BM- 000617660, G- 00236276, G- 00236277, G- 00236278, K- 000529253, OXF- 00194644, US- 02878809, fragment).

Rhytiglossa hookeriana Nees , Prodr. [A. P. de Candolle] 11: 348. 1847. ( Nees 1847 b: 348) Type. PERU. Amazonas, Chacapoyas, Sesuya, A. Mathews 3152 (holotype K- 000529384, isotypes BM- 000617661, G- 00236301, G- 00236302, GZU- 000251216 (fragment), K- 000529383, OXF- 00194660), syn. nov.

Dianthera hookeriana (Nees) Benth. & Hook. f. ex B. D. Jacks., Index Kew. 1 (2): 742. 1893. ( Jackson 1893: 742)

Ecbolium hookerianum (Nees) Kuntze, Revis. Gen. Pl. 2: 980. 1891. ( Kuntze 1891: 980)

Justicia chachapoyasensis Wassh., Monogr. Syst. Bot. Missouri Bot. Gard. 45: 1253.1993. ( Wasshausen 1993: 1253) Type. Based on Rhytiglossa hookeriana Nees

Type.

Based on Rhytiglossa cuspidulata Nees ,

Description.

Stems pubescent. Leaves petiolate, 2–4 × 1–2.5 cm, ovate, obovate or elliptic, apex acuminate to rounded, acute, apiculate or cuspidate, only slightly longer than broad, base cuneate, pubescent; petioles 0.5–1 cm. Inflorescence a terminal spike, 6–10 cm long, usually much exceeding the subtending leaf pair, flowers in opposite pairs, bracts narrowly deltoid-lanceolate, c. 5 mm long, bracteoles 6–8 mm long, narrowly linear-lanceolate, hirtellous, slightly exceeding the 4 - lobed calyx; calyx lobes 5–6 mm long, pubescent; corolla 12–18 mm long to apex of upper lip, pink, pubescent, lower lip slightly longer, spreading, lobed to 5 mm, lobes rounded; thecae weakly superposed, base muticous, c. 1 mm long. Capsule and seeds not seen.

Illustration.

Fig. 3 .

Phenology.

Found in flower in March.

Habitat.

Disturbed woodland, 697 m.

Distribution.

A rare species endemic to Amazonas Province and only known from the type and a single modern collection. Fig. 54 .

Material examined.

Peru • Amazonas: Prov. Utcubamba, Dist. Jamalca, between Bagua Grande and Pedro Ruiz, 5°52'41.5"S, 78°12'25.9"W, 697 m, 29 March 2024, D. Aybar 001 ( MOL) ; • ibid., 4 May 2024, D. Aybar 013 ( MOL) .

Notes.

Rhytiglossa cuspidulata Nees and R. hookeriana Nees were described by Nees in the same publication based on different sheets of the same collection number. Although the cuspidate leaves of the R. cuspidulata are very distinct at first glance from the acute to shortly acuminate leaves of R. hookeriana there is considerable variation in the various sheets of this collection at BM, K and OXF with varying degrees of intermixture. K- 000529252 has lower leaves shortly acuminate and apiculate, but the upper leaves rounded and cuspidate at apex. K- 000529384 has some leaves acute and some obtuse and mucronate. No other distinguishing characters are discernible. It seems difficult to maintain Rhytiglossa cuspidulata Nees and R. hookeriana as distinct taxa except possibly as forms so we propose they are treated under the oldest available name in Justicia , which is J. cuspidulata (Nees) Wassh. , J. hookeriana being already occupied as J. hookeriana (Nees) T. Anderson from Sri Lanka.

Ezcurra (2002) equated R. cuspidulata with plants of the Chaco but Wasshausen & Wood showed that the Chaco plants were a distinct species, Justicia praetermissa Wassh. & Wood ( Wasshausen & Wood 2003) .

Curiously, this plant was not recollected for over 150 years before David Aybar re-found it in March 2024. Photographs of this newly rediscovered species are shown in Fig. 3 .

Figures

Figure 3. Photographs of Justicia cuspidulata. Note the pink flowers with prominent “ herring bone ” patterning and obtuse leaves with short petioles. Photographs of Aybar 13 by David Aybar.

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.