Nasa loxensis Weigend
Creators: name: Henning, Tilo
name: Allen, Joshua P.
name: Montesinos-Tubeé, Daniel
name: Rodríguez-Rodríguez, Eric F.
name: Peña, José Luis Marcelo
name: Acuña-Castillo, Rafael
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Cornales
Loasaceae
Nasa
Nasa loxensis

description: Nasa loxensis (Kunth) Weigend in Weigend et al. Revista Peru. Biol. 13 (1): 77. 2006.
Fig. 3 A
Basionym.
Loasa loxensis Kunth, Nov. Gen. Sp. 6: 116.1823.
Holotype.
Ecuador • [Prov. Loja] Loxa, [Aug?. 1802], A. v. Humboldt & A. Bonpland 3349 (Holotype: P barcode P 00679495!)
Description.
Plants to ca. 1.5 m tall, covered with scabrid, glochidiate and stinging trichomes, glandular trichomes inconspicuous or absent. Stems erect, cylindrical, to 1 cm diam., base woody. Leaves opposite, petiolate, petioles 1–6 cm long, leaf blades pinnately veined, 3–14 × 2–8.5 (– 11.5) cm, triangular to ovate, with 1–6 lobes per side, widely triangular to ovate, apices acute or rounded, the largest of a leaf, 0.5–2 (– 4.5) × 0.4–2 (– 3) cm, the first or second often the largest (the third less commonly so), progressively smaller apically, margins serrate to denticulate, each tooth with a hydatode, base rounded, truncate or shallowly cordate (sinus to 5 mm deep), apex acuminate. Inflorescence a monochasial or dichasial cyme, 7–30 cm long, bracts alternate, one per flower, usually shorter and proportionally much narrower than the vegetative leaves, elliptical, 1–8 × 0.2–3.2 cm, diminishing in length, and particularly width, towards the inflorescence apex with 4–7, broadly triangular, shallow to very shallow lobes, base rounded. Pedicels 2.5–3.6 cm long in anthesis, often horizontal but ranging to 45 ° above or below the horizontal, the apex deflexed. Flowers deflexed, up to 7 per inflorescence branch. Sepals 5, ovate triangular, apex acute to acuminate, green, 0.7–1.3 × 0.4–0.7 cm, with three main veins, evidently much shorter than the petals. Petals 5, orange to red, shallowly cymbiform, base narrower than the limb but claw short and poorly differentiated (to 4 mm wide), 2.5–3.8 × 0.8–1 cm, with 3 evident main veins, tip acuminate, basal gaps between petals leave the scale bases visible (gaps often visible, sepals too short to hide them), corolla wider at base, tapering distally. Nectar scales 5, yellow to orange red, going from lighter yellow on the back to darker orange on sacs and red orange on neck, 11–16 mm long and ca. 3 mm wide at the base, basally on back with two depressed globose sacs 2 mm in diam., nectar scale back rectangular narrow, papillose, dorsal threads 0, 2 or 3, short, <1 mm long (very rarely longer), inserted subapically, scale neck thickened, slightly recurved, laterally protracted into two horizontal wings 5 mm long and 1 mm wide. Staminodia 2 per scale, 17 mm, narrowing apically, apex filiform, more or less sigmoid, slightly papillose, white. Stamens, usually extending beyond the petals during the male phase, in 5 antepetalous fascicles of 13–16 each, filaments to 30 + mm long, anthers 1.5 mm long and 1 mm wide, elliptical, cream before dehiscence, whitish when shedding pollen, black after pollen is shed. Ovary broadly conical or hemispherical, with a rounded base, to 7 × 5–6 mm, with 3 parietal placentae. Stigma lobes 3, shortly decurrent on the style surface, style to ca. 30 mm long. Fruit a clavate or cylindrical capsule with persistent sepals, pedicel erect, 25–55 mm long, mature capsule 21–27 (– 30) x 11–13 (– 14) mm (width at sepal insertion) including a short or elongated conical apical projection, opening by the three apically dehiscing valves, base rounded, less commonly tapering. Seeds numerous, dark brown, ovoidal, testa reticulate.
Notes.
For detailed information on identification, ecology etc. see notes under Nasa calycina. Across its distributional range, our redefined Nasa loxensis seems to show high uniformity in floral characters, although the observed leaf morphology can be significantly more diverse. The most unusual (and variable) leaf morphologies have been reported from the southernmost populations directly to the west and south of the city of Loja (Weigend 2000 b). Some plants in this area have leaf blades with very prominent, long lobes and deep sinuses, and are occasionally as wide as long. The reasons for the high foliar variability in this part of the range are unknown. Living plants that closely resemble the type material of Nasa loxensis (Humboldt & Bonpland 3349) have been collected from localities to the west and north of the city of Loja.
Specimens examined.
Ecuador. Cañar • Parroquia Rivera, sector Santo Tomás, vía a Monay, propiedad de Luis Méndez, 2754 m, 12 October 2000, A. Verdugo et al. 230 (HA) • Azuay Sevilla de Oro, 10–12 km N of village, 2750–2850 m, 11 September 1976, B. Øllgaard & H. Balslev 9331 (AAU) • The Eastern Cordillera, 1–8 km north of the village of Sevilla de Oro, 2400–2700 m, 27 July – 12 August 1956, W. Camp E- 4339 (P) • Gualaceo a Macas, a 12 km de Gualaceo, 6 August 1986, A. Freire-Fierro 251 (GB) • West of Patul 3 km between Huahualcay and Río Patul below Pasas de Pinglión, 2670–3275 m, 19 May 1943, J. Steyermark 52611 (F) • Mountains near Cuenca, August 1864, W. Jameson s. n. (E, US) • Rio Machangara, NW Cuenca, quebrada vegetation, 3000–3100 m, 18 September 1967, B. Sparre 18609 (US) • Sayausid, ca. 3000 m, 1 April 1968, G. Harling et al. 7942 (GB) • Mountains above Sayausid, 3000–3200 m, 18 March 1974, G. Harling & L. Andersson 12604 (GB) • Above Sayausí, at first bridge over Río Tomebamba. Secondary scrub, 3200 m, 3 March 1985, G. Harling & L. Andersson 22702 (GB, QCA) • Above Sayausí, trail to Cajas, 3300 m, 20 July 1939, C. Penland & R. Summers 1074 (F, US) • Río Mihuir (Miguir?) 1 km below Miguir on road Cuenca – Molleturo. Secondary scrub, 3400 m, 8 March 1985, G. Harling & L. Andersson 22915 (GB, QCA) • Cuenca, Cajas, Laguna Llaviuco (= Laguna Surocucho). Directly on the roadside, 3000–3150 m, September – October 1995, M. Weigend & S. Horn 3830 (F, QCA) • Area Nacional Recreacional Cajas, Sect. Llaviuco, 3300 m, 8 January 1991, S. León et al. 2509 (QCA) • Surucucho, 2800 m, March 1967, F. Vivar et al. 514 (Loja) • Cuenca, Sayausí, sector Dudahuayco, captación de agua. En sitios abiertos y pastizales, 3060 m, 20 July 2006, A. Verdugo & D. Minga 1678 (HA) • Cuenca, Sayausi. Road to Llaviucu lagoon, close to the intersection with the Cuenca-Molleturo road. Common in degraded vegetation on the roadside, 3024 m, 18 February 2017, R. Acuña & H. Garzón 1732 (QCA) • Las Cajas: near Laguna Llaviuco Montane forest and disturbed areas along the road, 3100–3200 m, 12 September 1983, B. Boysen Larsen & B. Eriksen 45098 (AAU) • Parque Nacional Cajas, Laguna de Llaviuco, 3170 m, 9 June 2011, C. Ulloa et al. 2137 (HA, QCA) • Fierroloma, Zorrocucho, en bosque primario, 3200 m, 15 January 1997, D. Minga 86 (HA) • Dudahuaycu, Mazán, 3500 m, 6 March 1991, G. Chacón 93 (HA) • 14 July 1994, G. Chacón 94 (HA) • A 1 km del control de la vía a Loja, partidero del lado derecho hacia Yanasacha, bosque secundario y pajonal, zona lluviosa, 3000–3200 m, 26 June 1978, J. Jaramillo & J. Boeke 412 (QCA) • Río Matadero valley near entrance to Parque Nacional de Cajas, 2900 m, 28 December 1979, L. Holm-Nielsen 20928 (AAU) • Sunsun-Yanasacha. Vía a mina de Caolín, cerca el río. En el sotobosque, 3100 m, 16 June 1999, F. Serrano et al. 718 (HA) • Vía partidero a Quinoas-Surocucho, 3000 m, 5 February 1978, F. Ortiz & J. Jaramillo 76 (QCA) • Portete del Tarqui and environs, remnants of montane forest, 2600–2700 m, 24 February 1993, G. Harling & B. Ståhl 26666 (QCA) • Tarqui, near the monument, 2600 m, 5 February 1982, G. Harling et al. 20247 (GB) • Victoria del Portete, sector Aguarongo y / o Caspishitana. En el sotobosque, 3584 m, 26 April 2006, A. Verdugo & D. Minga 904 (HA) • 15 km SW of Cuenca on road to Giron, 8 km SE on dirt road from Hacienda Tarquí turnoff, km 22, to Patococha, 2950 m, 30 May 1990, P. Peterson & E. Judziewicz 9359 (QCA) • Patacocha, 7–8 km by trail S of Hacienda Tarqui at Inquis, 3050–3100 m, 29 January 1988, U. Molau et al. 2750 (GB) • Victoria del Portete, Río Portete, sector captación de agua, 2778 m, 25 April 2006, A. Verdugo & D. Minga 887 (HA) • Sigsig to Gualaquiza, Rio Altarurcu (20 km E of Sigsig), 2800 m, 13 April 1968, G. Harling et al. 8309 (GB) • Cumbe, 2900 m, 22–24 April 1968, G. Harling et al. 8692 (GB) • 13 km S of Cumbe, 3300 m, 9 Jun 1979, B. Løjtnant et al. 14417 (AAU, GB) • Along Pan-American Highway, 40 km south of Cuenca, 3300 m, 20 September 1944, I. Wiggins 10761 (US) • Loja: Saraguro, camino Panamericana-Huashapamba, montaña húmeda, 2800–3000 m, 31 September 2004, A. Macas s. n. (CHEP) • Vicinity of Las Juntas, 28 September 1918, J. Rose et al. 23189 (US) • Between La Toma and Loja, 1800–2600 m, 4 September 1923, A. Hitchcock 21370 (US) • Road Catamayo (La Toma) - Loja, km 9 past junction with old road. Bosque húmedo remnants and secondary scrub, 2550 m, 28 April 1997, G. Lewis 3216 (E, Loja) • West of Loja, just over pass to Catamayo (Toma); 1 km south of Loma de Trigal, scrub forest, 5 May 1986, M. Baker 6959 (NY, US) • Cerro Villonaco, 2600–2750 m, 12 April 1974, G. Harling & L. Andersson 13461 (GB) • W Slope, 10 February 1985, G. Harling & L. Andersson 21862 (GB, QCA) • 1 March 1947, R. & A. Espinosa 1316 (Loja) • Cerro Uritusinga. Loja-La Palma, km 18–20. Montane forest, primary and secondary forest under heavy pressure, exploited to produce charcoal, 2910–3000 m, 30 November 1994, P. Jørgensen et al. 1040 (Loja) • Loja, 8 November 1876, E. André K- 546 (F) • Parte alta de Hacienda Montecristi, unos 40 km NE de Loja, curso del Río Zamora hacia el oriente, 8 June 1947, R. Espinosa 1471 (Loja) • Cantón Catacocha, El Almendral, Hacienda La Hamaca, 1800–2200 m, 16 April 1944, M. Acosta Solís 7902 (F) • Chepel, 2200 m, s. d., R. Espinosa 1978 (Loja) • Prov. Unknown: Herb. de Pérou, s. d. J. de Jussieu s. n. (P) • Équateur et Pérou, s. d., M. Grisar s. n. (P) • Warszewicz s. n. (F neg, No. 10202).
Photographic evidence (iNaturalist): (Note: due to Nasa loxensis s. l. being considered threatened by the IUCN, it was not possible to obtain the precise locality of some observations): Ecuador • Azuay: - 2.98455, - 79.07776, April 2023, Kabir Montesinos, http://www.inaturalist.org/observations/154122854 • Laguna Sorocuchu, - 2.84466, - 79.14866, April 2023, Kabir Montesinos, http://www.inaturalist.org/observations/153135367 • W del P. N. Cajas, - 2.89167, - 79.36357, May 2021, Kabir Montesinos, http://www.inaturalist.org/observations/80194774 • Cerca del Portete de Tarqui, - 3.08651, - 79.13816, March 2024, Kabir Montesinos, http://www.inaturalist.org/observations/204670994 • Cerca del Portete de Tarqui, - 3.08931, - 79.13622, November 2022, Kabir Montesinos, http://www.inaturalist.org/observations/141022114 • Carachula, - 3.14969, - 79.35685, June 2023, Kabir Montesinos, http://www.inaturalist.org/observations/167995363 • Loja: Washapamba, - 3.671097, - 79.252418, May 2023, LostInCR, http://www.inaturalist.org/observations/178891174 • camino de Washapamba a Cerro de Torre - 3.682952, - 79.244846, April 2022, Rudy Gelis, http://www.inaturalist.org/observations/118712124 • Province Undetermined: Aug. 2019, manuelganzhi, http://www.inaturalist.org/observations/31622038 • July 2020, Jonathan Aguirre Pesantez, http://www.inaturalist.org/observations/67707816 • June 2022, Jonathan Aguirre Pesantez, http://www.inaturalist.org/observations/121346890 • September 2022, bb_593, http://www.inaturalist.org/observations/134805560 • October 2022, bb_593, http://www.inaturalist.org/observations/137584820 • February 2022, Edgar Segovia, http://www.inaturalist.org/observations/106356391.
There are two observations from southern Cajamarca in Peru that are tentatively placed here. Since no herbarium material was available so far, we refrain from reporting a Peruvian distribution of this species for the time being. Peru • Cajamarca, - 6.47573, - 79.01225, August 2022, manuelroncal, http://www.inaturalist.org/observations/131296479 • - 6.23583, - 79.07411, August 2007, barbetboy, http://www.inaturalist.org/observations/15334620.
Distribution.
Nasa loxensis has a wide distribution in southern Ecuador, found in the provinces of Cañar, Azuay, Loja and apparently Morona-Santiago (Fig. 1). It is one of the most frequently collected species of Nasa in Ecuador as it can be found growing near human settlements, frequently visited national parks, and in both pristine and degraded habitats. At its southernmost distribution limits, it is suddenly replaced by Nasa calycina, farther to the SW, Nasa amaluzensis replaces both taxa. Further north in Tungurahua and Cotopaxi, similar Nasa auca can be found. As indicated above, a disjunct distribution at the southern end of the Amotape-Huancabamba Zone in Peru (Cajamarca, Prov. Chota) appears possible but needs further examination and material.
Phenology.
Flowering has been recorded every month of the year.
Tentative conservation assessment.
We recommend considering this species as NT. Although both its AOO (900 km 2) and EOO (12.193 km 2) could suggest a Vulnerable (VU) status like Cornejo and Suin (2011) recommended previously, these seem to be the only criteria that could justify such assessment as no other criterion appears to support a high-risk category. Nasa loxensis can be seen frequently in the W and S of the city of Cuenca and seems to be able to withstand some habitat degradation. Seemingly healthy populations are protected within the current limits of Cajas National Park.
description: Published as part of Henning, Tilo, Allen, Joshua P., Montesinos-Tubeé, Daniel, Rodríguez-Rodríguez, Eric F., Peña, José Luis Marcelo & Acuña-Castillo, Rafael, 2025, No end to endemism – contributions to the difficult Nasa Weigend Series Alatae (Loasaceae). A new species from Peru and the rehabilitation of " Loasa " calycina Benth., pp. 163-186 in PhytoKeys 252 on pages 163-186, DOI: 10.3897/phytokeys.252.141635