Passiflora justinianoi Kuethe, 2025

Kuethe, J. R., Wettges, Martin, Jiménez, Marco M. & Fuentes, Alfredo, 2025, A new section within Passiflora subgenus Decaloba (Passifloraceae) borne from the “ Passiflora lobbii group ”, with three new species from the montane forests of southern Ecuador and Bolivia, Phytotaxa 691 (2), pp. 173-187 : 181-182

Passiflora justinianoi Kuethe sp. nov. ( Figures 3–4B )

Type: — BOLIVIA. Cochabamba department: Tablas Monte region , road between Paracti and Corani Pampa, 17°09’01.7”S 65°54’42.4”W, 2497 m, 7 December 2023 (fl.), Hermes Justiniano, J.R. Kuethe, Mattias Lanas, Ramón Vargas, Miguel Molinari 136 (holotype: USZ!; isotypes: LPB, USZ!, BOLV!) .

Diagnosis: This new species is similar to Passiflora solomonii and Passiflora lobbii , from which it differs by being glabrescent to sparsely pubescent throughout (vs. glabrous [former] or firmly pubescent [latter]), the ovate reddish stipules (vs. setaceous and brownish), the absence (vs. presence as in P. lobbii ) of the petiolar nectaries, and the small, greenish-white flowers with a straight corona (vs. greenish-brown or greenish yellow in which the corona is slightly wavy).

Description: — Plant a trailing vine with long trailing branches of 3–5 m, glabrescent to sparsely pubescent throughout. Stem green, lighter green when young, terete. Internodal distance 1–4 cm. Stipules distinctly reddish in color, with a slight brownish tip, ovate, 2.5–3 mm long, 1–1.3 mm wide. Petiole 1.6–2.4 cm long, terete, eglandular, often slightly crooked in the basal 1/3 rd, green. Leaf blade transversely ovate to lanceolate, terminating in long acute apices, distinctly 2-lobed to obscurely 3-lobate, (9–)12–15(–17) cm wide, 1.5–2.2 cm long when measured along the central vein, length of the lateral veins 6.1–7.7 cm, lobes long lanceolate, narrow, base of the blade very shallowly cordate, apices acute; the central lobe (if present) very broadly deltoid with mucronate apex, sometimes slightly emarginate; slightly truncate when absent, foliar texture coriaceous to membranous, green adaxially, lighter green abaxially. Inflorescence in pairs, borne on long peduncles of no more than 15–22 mm, articulated at about 1/3 rd below the base of the flower. Bracts obscure, setaceous, 0.8–1 mm long, reddish. Flowers greenish white, 19–22 mm wide, inconspicuous individually, though inflorescences numerous; hypanthium disc-shaped, slightly pentagonal in outline, 6–7 mm wide, about 1 mm high; sepals ovate-lanceolate, 8–9 × 2.5–3.3 mm, apices acute to sharply obtuse, greenish white, ecorniculate; petals short and feeble, linear, 3–3.7 × 1.8–2.1 mm, apex obtuse to slightly praemorse, white, membranous; corona uniserial, filaments whitish-green becoming a deeper green at base, filiform, radiate, 5–6 mm long, straight; operculum clavate to plicate, reddish to purplish-red with a whitish ridge, folded, margins serrate, about 1–1.2 mm long; limen absent; androgynophore small, about 3 mm high, green; stamen approximately 2–3 mm long, green, pollen light yellow; ovary oval, green, glabrous, 1–1.5 mm high; style ca. 2–3 mm long, green, stigma green, globose, <1 mm. Fruit a small greenish to greenish-yellow berry, ellipsoid to ovoid with five distinct raised ridges, 12–15 × 6–7 mm when mature; mesocarp about 1 mm thick, whitish-green; pulp a pale yellow to white, with 15–25 black seed per fruit; seed ovoidal, ca. 1–1.5 × 0.7–0.9 mm, resticulate.

Phenology: —This tiny species has been observed with flowers in November and December, carrying fruits from December to January.

Distribution and habitat: — Passiflora justinianoi can be found in the montane cloud forests of the Tucumano- Boliviano ecoregion in central Bolivia. It is found almost exclusively within the department of Cochabamba, where it grows as a feeble trailing vine along the western fringes of the Carrasco Natural Park. Numerous populations were seen along the road between Paractí and Cochabamba, and along the tracks and trails into the montane Inca villages Tablas Monte, Corani-Pampa and Ichuloma, where it was seen growing primarily within the understory of the steep mountain forest. A smaller population of P. justinianoi was seen in the Santa Cruz department within the Amboró National Park inland from Samaipata. This small species is found in montane Andean cloud forest at elevations between 2,200 and 2,850 meters, where it grows with long trailing branches next to roadsides and near farmed areas.

Etymology: —This species is dedicated to Hermes Justiniano, Bolivian botanist and founder of the Fundación para la Conservación del Bosque Seco Chiquitano (FCBC), who contributed profoundly to the studies of the Bolivian Passiflora through his comprehensive fieldguide and other publications.

Preliminary conservation status: —With an Extent of Occurrence (EOO) of about 1,500 km 2 and an Area of Occupancy (AOO) of about 45 km 2, P. justinianoi scales EN (Endangered) in accordance with the GeoCat software. However, during field work conducted in 2023, the authors found the species growing in great numbers along roadsides and near farm fields, indicating the species is fairly resilient against habitat disturbances. The second population found in the Amboró National Park, additionally, widened its natural range well beyond several habitats and environmental dynamics, making the species much more adaptable than its poor herbarium presence makes it seem. For these reasons, the authors conceive the conservation status of VU to NT as being more appropriate based on its current field abundance seen within both disturbed and pristine habitats, with IUCN (2022) categories C and D1 and D2 appearing to be inapplicable.

Additional specimens examined (paratypes):— P. justinianoi : Bolivia. Cochabamba: Chapare region, Municipio Colomi. Sobre el camino hacia Tablas Monte, cercanías de la localidad Apaza, 17°08’06”S 065°55’26”W, 2437 m, 03 January 2016, Hermes Justiniano, N. de la Barra, Gyna Foianini 16 ( USZ); Tablas-Monte cerca del pueblito, 17°05’22”S 065°59’41”W, 2274 m, 31 December 2020, Hermes Justiniano 48 ( USZ); Rio Aliso-Mayu – Rio Derrumbe-Mayu, 17°08’S 065°54’W, 2500 m, 24 June 1995, Nur Ritter, John Wood 2332 ( LPB); entre Siberia y Fortaleza, 17°45’S 064°44’W, 2200 m, 1 February 1992, Roberto Vásquez 1958 ( BOLV); By the road to Incachaca from the checkpoint on the Cochabamba-Chapare road, 17°13’46”S 065°49’04”W, 02 April 1995, John Wood 9621 ( LPB). Santa Cruz: Comarapa, bajando a Locotal, 17°47’14”S 064°43’20”W, 2140 m, 09 March 2021, Alfredo F. Fuentes, Moisés Mendoza & Rossy-Mar Montaño 21879 ( LPB, MO).

Figures

FIGURE 3. Passiflora justinianoi sp.nov. LCDP (Lankaster Composite Dissection Plate). A. Habit, B. Leaf, adaxial side (B 1) and abaxial side (B 2). C. flower bud. D. flower, showing front (D 1) and back (D 2), and longitudinal section (D 3). E. stipule.F. fruit. Composed of photos taken by J.R. Kuethe and Hermes Justiniano.

FIGURE 4. Comparative rubric of the habit and flower between Passiflora solomonii Escobar (A) from its type locality; Passiflora justinianoi sp.nov. (B); and Passiflora lobbii ssp. charazanica subsp.nov. (C). Photo courtesy of J.R. Kuethe.