Capsicum eximium Hunz., Darwiniana 9(2): 235. 1950.

Barboza, Gloria E., Garcia, Carolina Carrizo, Bianchetti, Luciano de Bem, Romero, Maria V. & Scaldaferro, Marisel, 2022, Monograph of wild and cultivated chili peppers (Capsicum L., Solanaceae), PhytoKeys 200, pp. 1-423 : 1

16. Capsicum eximium Hunz., Darwiniana 9(2): 235. 1950.

Figs 59 , 60

Type.

Argentina. Salta: Dpt. Guachipas, Quebrada de San Antonio, Pampa Grande, 1600 m elev., semillas del ejemplar A. T. Hunziker 1907, cultivadas en el Jardin Botanico de la Facultad de Agronomia y Veterinaria de Buenos Aires, 4 Mar 1943, A.T. Hunziker 7346 (lectotype, designated by Barboza 2011, pg. 30: CORD [CORD00006579]) .

Description.

Erect shrubs or subshrubs, 0.5-3 (-4) m tall, the main stem thick, up to 6 cm in diameter at base, much branched from near the base, the branches fragile, flexuous, fragile in a typical “zig-zag” appearance above. Young stems strongly angled, fragile, green, moderately pubescent with antrorse, flexuous, simple, uniseriate, 4-7-celled, eglandular trichomes 0.5-1.6 mm long and sparse minute glandular trichomes (stalk short, translucent, 1-2-celled; head dark, multicellular); bark of older stems greyish-white, brown or dark green, fissured, glabrous; lenticels absent. Sympodial units difoliate, the leaves geminate; leaf pair more or less similar in size and shape. Leaves membranous, slightly discolorous or concolorous, glabrescent on adaxial and abaxial surfaces and margins with sparse eglandular trichomes like those on stems, but abundant in a tuft of trichomes in the basal vein axils and spreading along the mid-vein abaxially; blades of major leaves 3.4-12.5 cm long, 2.1-5 (-6) cm wide, ovate or elliptic, the major veins 4-5 on each side of mid-vein, the base attenuate or cuneate and asymmetric, the margins entire, the apex acuminate; petioles 1-2.5 cm long, glabrescent or glabrous; blades of minor leaves 3-4 cm long, 1.3-2 cm wide, ovate or elliptic, the major veins 3-4 on each side of mid-vein, the base attenuate, the margins entire, the apex acute; petioles 0.3-0.5 cm long, with the same pubescence as the major leaves. Inflorescences axillary, 2-5 flowers per axil or flowers solitary; flowering pedicels 6-18 mm long, strongly angled, erect, geniculate at anthesis, green, scarcely to moderately pubescent with eglandular and glandular trichomes; the eglandular trichomes short, antrorse; pedicels scars inconspicuous. Buds globose or ovoid, fairly inflated, lilac, purple or yellowish-green. Flowers 5-merous, occasionally perianth 4-merous. Calyx 2-2.5 mm long, ca. 3 mm wide, cup-shaped, thick, green, green with purple spots or purple, moderately pubescent with the same eglandular and glandular trichomes as the stem, the calyx appendages (4-) 5, 1.2-2.7 (-3) mm long, subequal, thick, erect or slightly spreading, cylindrical or laterally compressed, inserted close to the margin, sparsely pubescent with the same trichomes as calyx tube or glabrescent. Corolla 5-8.5 mm long, 9-11 mm in diameter, lilac or purple or white with lilac and greenish-yellow spots outside, lobes marginally or completely lilac, purple or magenta, tube greenish-yellow or ochre and white centre within, sometimes the purple pigmentation is lacking, stellate with interpetalar membrane, 5 (4-)-lobed, halfway or less of the way to the base, pubescent adaxially with a continuous ring of long glandular trichomes (stalk 2-3-celled; head globose, unicellular) in the throat and up to near the base of the lobes, glabrous abaxially, the tube 3-4 mm long, the lobes 3-4.4 mm long, 2.4-3.6 mm wide, triangular, spreading, the margins finely ciliate, the tips acute, papillate. Stamens five, equal; filaments 2.7-3.8 mm long, white or lilac, inserted on the corolla 1-1.5 mm from the base, with auricles fused to the corolla at the point of insertion; anthers 1.7-2.1 mm long, ellipsoid or ovoid, yellow or purplish, not connivent at anthesis. Gynoecium with ovary 1.3-1.8 mm long, 0.9-1.5 mm in diameter, green, ovoid; ovules more than two per locule; nectary ca. 0.4 mm tall; styles homomorphic, 3.5-4.5 mm long, barely exserted beyond the anthers, lilac or white, clavate; stigma ca. 0.2 mm long, 0.5 mm wide, discoid, pale green. Berry 7-10 mm in diameter, globose, green or green with black or violet spots turning to dark brown when immature, bright red at maturity, deciduous, pungent (in some populations non-pungent), the pericarp thick, opaque, with giant cells (endocarp alveolate); stone cells absent; fruiting pedicels 14-24 mm long, erect, strongly angled, widened distally, green or purplish-green; fruiting calyx 3-5 mm in diameter, persistent, not accrescent, discoid, green or purple, the appendages 1-3.3 mm long, spreading or reflexed. Seeds 7-17 per fruit, 2.8-4.2 mm long, 2.1-3 mm wide, C-shaped or subglobose, brownish-yellow, the seed coat faintly reticulate (SM), reticulate-cerebelloid (SEM), the cells irregular in seed body and polygonal at margins, the lateral walls sinuate in seed body, straight to wavy at margins; embryo imbricate.

Distribution.

Capsicum eximium occupies a continuous area from northern Bolivia (La Paz, Potosí, Cochabamba, Santa Cruz, Chuquisaca and Tarija Departments) to northern Argentina (Jujuy, Salta and Tucumán Provinces) (Fig. 61 ). Its southern-most distribution (Argentina, Tucumán) needs to be re-confirmed since the two extant collections date from a hundred years ago.

Ecology.

Capsicum eximium grows preferentially in dry mesothermic and sub-Andean valleys with deciduous forest and scrub (Chaco), in pastures or on the edge of cultivated fields; it is often found on steep or gentle slopes, along dried watercourses or in remnant of forests dominated by Mimosoideae , Schinopsis or cacti, between 1,000 and 3,000 m elevation.

Phenology.

Flowering from November to April; fruiting from late December to May.

Chromosome number.

n = 12 (Heiser and Smith 1958); 2 n = 2x = 24 ( Pickersgill 1977; Moscone et al. 2003, 2007).

Common names.

Argentina: Ulapuca (Salta, Lahitte s.n.), Ulupica (Salta, Schinini et al.34774), Ají cobincho (Salta, Hilgert 2061); Bolivia: Ulupica (Cochabamba, Peñaranda 458; La Paz, Beck 25261; Potosí: Zamora 193; Santa Cruz, Vargas C. 1382), Ají ulupica (Tarija, Manchego CEP T21), Ulupica muruchi, Ulupica negra semiosca, Ulipica grande hosca, Ulupica tuna, Ulupica negra neta, Ulupica blanca, Ulupica verde, Ulupica camba, Ulupica negra con flor blanca (Chuquisaca, Libreros et al. 2014).

Uses.

The fruits are very pungent and are used as spices or in pickles in the Bolivia ( National Research Council 1989; Jäger et al. 2013) and Argentina ( Eshbaugh and Smith 1971; Barboza, pers. obs.). Fresh or dry fruits are powdered to prepare a sauce known as “llaswa” (see details in C. cardenasii ) that people add to “empanadas” (little meat pies) in Argentina; ‘ulupica’ is not only an ingredient in “llaswa”, but also in many recipes in Bolivia.

Preliminary conservation assessment.

EOO (278,222.889 km2); AOO (396 km2). Capsicum eximium is found over a large extent of occupancy from northern Bolivia to northern Argentina and is common in the inter-Andean valleys. We suggest the status of Least Concern (LC). It is a species of open areas, forming small populations and is sometimes cultivated on farms for self-consumption of the fruits.

Discussion.

Capsicum eximium is a member of the Purple corolla clade ( Carrizo García et al. 2016). New preliminary evidence on the affinities of species in this clade is discussed under C. pubescens . Capsicum eximium is the most widespread ‘ulupica’ with corolla colour as its most variable character (Fig. 60H-N ). Eshbaugh (1982) pointed out that, within the same population, he could observe individuals with white, cream or purple corollas; he also associated this variation with the distribution of the species, indicating that the forms with white corollas were restricted to the northern part of its range while populations with purple corollas occurred in southern Bolivia (Tarija). Data from modern collections reinforce that there is high inter- and intrapopulation variability in corolla colour (e.g. Nee 37575, Barboza et al. 4895 & 4896); this deserves further field studies to better understand if populations with white corollas (as stated in many herbaria labels, for example, Vargas C. 36 & 816, Cárdenas 4237, Saravia Toledo 12126, Wood 20218) refer to entirely white corollas or white corollas with greenish-yellow centres (e.g. Mendoza 801, Novara 8346, Barboza 4914).

The pungency of the fruits is polymorphic in C. eximium as it is in C. chacoense and C. baccatum ( Tewksbury et al. 2006), C. flexuosum and some cultivars of the domesticated species of the C. annuum complex ( Carrizo García et al. 2016). In Bolivia (Tarija), individuals of C. eximium from the same locality have been observed to have pungent and non-pungent berries (Manchego CEP T21 & Manchego CENP T22).

Capsicum eximium is a self-compatible species ( Eshbaugh 1979; Onus and Pickersgill 2004). Its affinity with C. cardenasii has been confirmed by breeding studies (Heiser and Smith 1958; Eshbaugh 1976, 1979; Onus and Pickersgill 2004), chemotaxonomic and cytological work ( Jensen et al. 1979; McLeod 1979a, 1979b, Moscone et al. 2007) and molecular evidence ( Carrizo García et al. 2016, 2020). Morphologically, they can be distinguished by leaf size (smaller in C. cardenasii ) and corolla shape (campanulate in C. cardenasii and stellate in C. eximium ). Eshbaugh (1976) has demonstrated that C. eximium and C. cardenasii interbreed freely and produce fertile hybrids; he also stated that it is possible to find intermediates between the two taxa (no vouchers cited, Eshbaugh 1982). Capsicum eximium also hybridises naturally with C. pubescens , a domesticated species with purple corollas ( Eshbaugh 1979, 1982; Barboza, pers. obs.). The collection Barboza et al. 1849 from La Paz (Bolivia) is an intermediate with the pubescence and corolla shape (stellate) of C. eximium and the corolla size and colour (purple) and fruit size of C. pubescens ; no seeds were observed. Similar specimens have been collected recently from experimental crossings between the two taxa made at a rural farm in Chuquisaca Department, Bolivia (Barboza et al. 4925 & 4926).

Specimens examined.

See Suppl. material 4: Appendix 4.

Figures

Figure 59. Capsicum eximium A flowering branch B flower C eglandular trichome of the calyx D opened corolla E, F anthers, dorsal and ventral views, respectively G gynoecium H fruit I seed J seed, in cross section K embryo A from Hunziker 7346 B-K from Hunziker 1907. Drawn by N. de Flury. Published in Barboza (2013), courtesy of the Board of the Instituto Darwinion (San Isidro, Buenos Aires, Argentina), reproduced with permission.

Figure 60. Capsicum eximium A plant (wet habitat) B plant (dry habitat) C main fissured stem D young inflorescence E-G flower buds with different colouration H-K flowers, in front view, with different corolla colouration within L flower, in lateral view M, N flowers seen from behind O mature fruits A, G, N from Barboza et al. 4914 B, E, M from Barboza et al. 4885 C, K from Barboza et al. 4903 D from Wageningen Netherlands University germplasm collection F, I from Barboza et al. 4895 H, O from Barboza 1919 (cult.) J from Barboza et al. 4896 L from Barboza et al. 3543 A-C, E-O photos by G. E. Barboza, D photo by P. Bosland.

Figure 61. Distribution of C. eximium and C. flexuosum.