Opuntia lasiacantha Pfeiffer (1837: 160)

Neotype (designated by Scheinvar et al. 2010: 280): — MEXICO. Guanajuato, San Luis de la Paz, 25 May 1999, Reyes-Agüero & Carlín 1857 (MEXU!).

Description:— Arborescent habit, 2.0–3.0 m high (Fig. 7A). Defined trunk of 50 cm in diameter, slightly grayish scaly bark with light brown tones (Fig. 7B). Glabrous epidermis (Fig. 10C). Oblanceolate to obovate cladodes, 45–62 cm long x 24–29 cm wide, green in color, covered with a layer of wax (Fig. 8A). Areolas arranged in 11–12 series, 3.8 cm spacing between series, 3.1 cm spacing between elliptical areolas, 0.4 × 0.3 cm, short black trichomes (Fig. 8B). Short yellow glochids (0.2 cm), arranged at the top of the areola. 1–4 yellowish white, rigid, cylindrical spines, some twisted, erect, and diffuse, unequal 0.4–3.3 cm long (Fig. 8C) with yellow apex. Juvenile cladodes with very prominent tubers, areolas with short yellowish trichomes, subulate, erect, green leaves with slightly uncinate reddish apex (Fig. 7C). Acute flower buds, reddish perianth segments with acuminate apex, slightly cylindrical pericarpel, very marked and elevated tubers, areolas with short brown to black trichomes, yellow glochids and areolas with generally yellow bristles and small brown shades (Fig. 8D and 8E). Yellow flowers (Fig. 8F), 9–10.5 cm long, cylindrical pericarp, ca. 6.0 × 2.5 cm, areolas arranged in 6–7 series, 0.42 cm spacing between them, with crass basal scale, outer obovate segments of perianth, acuminate apex, smooth yellow edges, with medium reddish striation, reddish apex, inner obovate segments, emarginated apex, upper yellow edges generally smooth, stamens 1/3 of the length of the perianth, white filaments, white-yellowish anthers, slightly cylindrical style with white with pink tones, ca. 2 cm long, usually eleven green papillary lobes of the stigma, ca. 0.6 cm long (Fig. 9B). Pyriform to elliptical red fruits (Figure 9C), 8.0– 9.3 cm long, slightly sunken floral striated scar, large areolas with short, black, semicircular to circular trichomes (Fig. 9E), arranged in 6–7 series, 1.2 cm spacing from each other and 1.4 cm between series, absent spines, yellow glochids, orange-red juicy and sweet funicles (Fig. 9D). Kidney shaped seed with irregular lateral aril, lateral thread-micropillar region, microphile and funiculus included (Fig. 9F).

Micromorphology:— Thornswith lignified epidermal cells 12.72 ± 1.4 × 3.95 ± 2.3 μm in the distal part (Fig. 10B), 75.11 ± 1.10 × 8.89 ± 1.7 μm, continuous epidermal cells and rough texture, in the middle part (Fig. 10A). Glabrous epidermis, irregular epidermal cells (Fig. 10C) and paracytic stomas (Fig. 10D). Polyhedron-shaped pollen grain, pantoaperturate (Fig. 10E), 105.10 ± 1.50 μm in diameter, 8327.73 μm ² in area, 15.30 ± 1.1 μm distance between each distal opening (pores), with a diameter of 20.15 ± 1.50 μm, 16–18 pores with walls of 2.46 ± 0.04 μm width and wart (Fig. 10F).

Vernacular names:— Nopal de tuna colorada, Nopal de espinas lacias and Nopal de cerro (see e.g., Anderson 2001, Scheinvar 2004).

Phenology:— Opuntia lasiacantha blooms from March–April, whereas fruiting time if June–July.

Habitat and distribution:— Endemic to Mexico, it is known in the states of Aguascalientes, Chiapas, Ciudad de México, Durango, Guanajuato, Guerrero, Hidalgo, Jalisco, México, Michoacán, Oaxaca, Puebla, Querétaro, San Luis Potosí, Tamaulipas, Tlaxcala, Veracruz and Zacatecas (see e.g., Arias et al. 1997, Guzmán et al. 2003, Scheinvar 2004, Scheinvar et al. 2010, Arias et al. 2012, Hernández et al. 2014) (Fig. 2). It grows in xerophytic scrub (Rzedowski 1978).