Polylepis quadrijuga Bitter, Bot. Jahrb. Syst. 45: 613, pl. 6. 1911.

Boza Espinoza, Tatiana Erika & Kessler, Michael, 2022, A monograph of the genus Polylepis (Rosaceae), PhytoKeys 203, pp. 1-274 : 1

19. Polylepis quadrijuga Bitter, Bot. Jahrb. Syst. 45: 613, pl. 6. 1911.

Figs 53 , 54

Polylepis boyacensis Cuatrecasas, Revista Acad. Colomb. Ci. Exact. 4: 343, f. 13-14. 1941. Type. Colombia. Boyacá: Cordillera Oriental, Páramo de Santa Rosita between Belen and Susacon, 3300-3400 m, 3 August 1940, Cuatrecasas 10374 (holotype: P!; isotypes: COL!, US!).

Polylepis cocuyensis Killip & Cuatrecasas, Revista Acad. Colomb. Ci. Exact. 5(17): 33. F. 19.1942. Type. Colombia. Boyacá: Nevado del Cocuy in the Quebrada of San Paulino, El Morrón, 3800 m, 11 September 1938, Cuatrecasas 1405 (holotype: US!; isotypes: P!, U!).

Type.

Colombia. Cundinamarca: Cordillera Oriental, Páramos de Bogota, Muzo , May 1844, Goudot s.n (holotype: P!) .

Description.

Trees 2-10 m tall. Leaves slightly congested at the branch tips, imparipinnate with 3-4 pairs of lateral leaflets, obtrullate in outline, (4.2-)4.4-5.3(-6.5) × 2.4-3.2 cm; rachises densely tomentose, points of leaflet attachment with a tuft of long, lanate hairs; stipular sheaths apically acute with spurs, densely lanate on the outer surfaces; leaflets elliptic in outline, second pair from the terminal leaflet the largest, one of this pair 1.5-2.0 × 0.7-1.1 cm; margin entire or slightly crenate with 4-6 teeth, apically emarginate, basally unequally cordate; upper leaflet surfaces glabrous; lower leaflet surfaces densely tomentose with whitish hairs 0.7-0.9 mm long. Inflorescences pendant, (6.0-)7.3-10.5(-12.3) cm long, bearing 11-19 flowers; floral bracts 4.3-4.7 mm long, narrowly triangular, densely lanate on the outer surface; rachises tomentose. Flowers 6.8-9.5 mm diam.; sepals 4, ovate, green, densely tomentose outside; stamens 9-19, anthers orbicular, with a dense tuft of straight white hairs on the upper half; styles fimbriate, 3.7-4.6 mm long. Fruits turbinate, with variable numbers and placement of flattened spines, densely villous; 4.6-6.5(-7.2) × 5.1-7.2 mm including spines. Diploid.

Distribution, habitat, and ecology.

Polylepis quadrijuga is found in north-eastern Colombia from Páramo de la Rusia (Santander) across Páramo Guina, Páramo Belen, Páramo Guantiva and Sierra Nevada Cocuy ( Boyacá) to Maciso de Sumapáz and Chingaza National Natural Park (Cundinamarca) (Fig. 61 ). It grows in humid Páramos at 2200-4250 m elevation. Polylepis quadrijuga represents 33.7% (1032.2 ha) of the total area of Polylepis forest identified for Colombia ( Fadiño and Caro 2009). It is often associated with Diplostephium tenuifolium ( Asteraceae) and Escallonia myrtilloides ( Escalloniaceae) ( Rangel-Ch and Arellano 2010).

Conservation status.

The estimated EOO for Polylepis quadrijuga is 16,286 km2 and the AOO is 84 km2. It is known from 16 locations. Polylepis quadrijuga is protected within Chingaza and Sumapaz National Natural Parks and Cocuy National Park. Although the species occurs within these protected areas, it is also found in heavily fragmented forest regions. Perhaps the most worrying area is the corridor Rusia-Guantiva Páramos because of the absence of protected areas that would help to mitigate the current pressures ( Rangel-Ch and Arellano 2007). The rising of the potato crop line is a strong threat to the permanence of these forests ( Rangel-Ch and Arellano 2010), as is the reduction of the potential range due to climate change ( Caballero-Villalobos et al. 2021). We assess P. quadrijuga as Vulnerable (A2a, B1a+B2a, D2a).

Notes.

Polylepis quadrijuga resembles P. frontinensis . It differs from it by its elliptic leaflets with tomentose hairs 0.7-0.9 mm long, whereas P. frontinensis has obovate leaflets with villous hairs 1.4-1.8 mm long. Further, P. quadrijuga is morphologically similar to P. occidentalis , with which it shares elliptic leaflets, with deeply emarginate apices, entire to slightly crenate margins and densely tomentose lower leaflet surfaces. However, P. quadrijuga has broader leaflets 0.7-1.1 cm, longer lower leaflet surface hairs 0.7-0.9 mm, longer inflorescences 6.0-12.3 cm, bearing 11-19 flowers and longer styles 3.7-4.6 mm, whereas P. occidentalis has leaflets 0.5-0.8 cm width, lower leaflet hairs 0.3-0.6 mm long, inflorescences 2.4-6.7 cm long with 4-12 flowers and styles 1.5-2.0 mm long.

Specimens examined.

Colombia. Boyacá: Duitama, Corregimiento El Carmen, vía a Virolin , Paramo de La Rusia , 3400-3500 m, 19 November 1994, Betancur 5610 (COL!); Paramo de Rusia. Km 3 from the summit of the road Duitama-Abendaños, 3500 m, 12 February 1999, Stancík 2384 (COL!). El Cocuy, Cordillera Oriental, Sierra Nevada del Cocuy , Quebrada de San Paulino próximo Alto Ritacuva, 3500 m, 07 April 1959, Barclay 7303 (COL!, MO!); Cocuy National Park , Concavito Valley , 06°25'39"N, 072°19'15"W, 4000 m, 07 February 2017, Olivares 570 (Z!). Guicán, Guican. Alto de la Cueva limite Cocuy-Guican, Finca Eudoro Carreño y Margarita Carreño, estación del Himat, 06°24'33"N, 072°22'40"W, 3930 m, 14 October 1996, Cruz 164 (COL!). Susacon, 20 km passing Sussacon in direction to soata, 3150 m, 23 February 1999, Stancík 2463 (COL!). Cordillera Oriwntal; Paramo de Guina-Santa Rosita , 3300-3400 m, 03 August 1940, Cuatrecasas 10374 (US!); NNW de Duitama , Paramo de La Rusia , Avenida de Penas Negras (Buenos Aires), 3550 m, 11 September 1989, Cuatrecasas 27741 (COL!); Hoya del Rio Cusiana , Vadohondo, 2880 m, 31 March 1973, Cuatrecasas 28708 (COL!); Mpio. de Guican , vereda La Guaca, El Junco, 3716 m, 23 July 1981, López s.n (COL!); arriba de la confluencia con el rio Upia , Rio Olarte , 3015 m, 27 February 1955, Molano s.n (COL!); Paramo de Colorado , 3200 m, 11 May 1960, Montenegro 2717A (COL!). Cundinamarca: Pasca, Vereda Cajita, borde de Laguna Cajitas en el Paramo de Chisaca , 3700 m, 04 October 1983, Sarmiento 2000 (COL!). Santafé de Bogotá, Macizo de Sumapaz ; Cuchilla La Rabona , 04°04'40"N, 074°13'00"W, 3900-3950 m, 17 July 1981, Díaz 2902B (COL!, MO!); Bogotá, D.C. Paramo de Sumapaz. ladera de la laguna Tunjos ( Chisacá), 04°16'36"N, 074°12'17"W, 3725 m, 19 February 1997, Franco 5632 (COL!, MO!). Subachoque, Vereda Tobal, 2800 m, 09 November 2003, Hernández 1407 (COL!); carretera Cogua-San Cayetano, cebeceras Rio Guandoque , 3 km al SW de la Laguna Verde, 3400 m, 01 June 1972, Cleef 4213 (COL!); Macizo de Bogotá, eastern slopes of Paramo de Chisaca. Quebrada de Santa Rosa , subPáramo, 3300-3350 m, 16 September 1961, Cuatrecasas 25999 (COL!); Dist. Especial de Bogotá; cordillera Oriental; lagunas de Chisacá; 40 km al N de Sumapaz, 3300-4000 m, 10 September 1959, García 17192 (AAU!); Fomeque, Paramo de Chingaza , a orillas de La Laguna, 3200 m, 03 November 1966, Huertas 6565 (COL!); Mpio. Bogota, Paramo de Sumapaz , entre la Laguna de Chisaca y Santa Rosa, 01 May 1989, Mahecha 10121 (COL!); Usme, al sur de Bogotá, 01 January 1944, Ranghel s.n (COL!); Macizo de Sumapaz , cerca a Santa Rosa, 3600-3700 m, 30 September 1963, Uribe 4491 (COL!) . Santander: Encino, Vereda Rionegro, Microcuenca de la quebrada Chontales , 05°59'N, 073°04'W, 3400-3500 m, 15 December 1999, Galindo 300 (COL!) .

Figures

Figure 53. Polylepis quadrijuga Bitter A flowering branches B habit C habit. Scale bars: 3 cm (A). Photographs by D. Cabrera.

Figure 54. Polylepis quadrijuga Bitter A flowering branch B stipular sheaths C inflorescence D upper leaf surface E lower leaf surface (A Montenegro 2717 B Huerta 6565 C Cuatrecasas 27741 D, E Stancik 2463). Scale bars: 3 cm (A); 4 cm (C); 2 cm (D, E). Photographs by J. M. Velez.

Figure 61. Geographical distribution of the species of section Polylepis Reticulatae.