Ainea conzattii var. macropetala Martorell, Espejo & López-Ferr., 2023

Martorell, Carlos, López-Ferrari, Ana Rosa, Espejo-Serna, Adolfo, García-Meza, Diego & Clayton, Rupert, 2023, Ainea conzattii (Iridaceae: Tigridieae) revisited: description of a new variety, Phytotaxa 600 (1), pp. 1-6 : 3-5

Ainea conzattii var. macropetala Martorell, Espejo & López-Ferr. , var. nov.

( Figures 2B–D ; 3 )

Type:— MEXICO. Oaxaca: District of Coixtlahuaca, Municipiality of Tepelmeme Villa de Morelos, paraje Loma Amarilla , 2075 m, 17°52’54”N, 97°20’40”W, pastizal de Aristida , 9 July 2022, Y. Mora et al. X976 (holotype UAMIZ!; isotypes: FCME!, MEXU!) .

Nova varietas ab originali varietate differt in illis quae tepalis internis (petalis) similibus in forma et magnitudine tepalis externis (sepalis) vs. tepalis internis multo minora quam externis.

Herbs 15–40 cm high. Bulbs ovoid to subglobose, 1–2.3 cm long, 9–18 mm diameter, covered by numerous dark brown cataphylls, sometimes extending upwards to form a 2–2.5 cm long collar at the base of the plant; basal leaves 2–5, green, linear, 10–20 cm long, 0.25–1 mm broad, acerose at the apex, old leaf bases remaining on plant, fibrous in appearance. Inflorescence one per plant; peduncle 13–22 cm long, ca. 1 mm diameter, cylindrical, glabrous, with a single linear-filiform bract at the base of spathes, 5–9 cm long; spathes sessile, 2–4.5 cm long, lanceolate, equal to subequal, convolute, the outer one longer than the inner one; rhipidium with 2–3 flowers, pedicels shorter than the spathes, filiform, glabrous. Flowers actinomorphic; perigonium 2.8–4 cm diameter; outer tepals white, elliptic to obovate, 1.4–2 cm long, 9–12.5 mm wide, rounded at the apex; inner tepals white with two basal lateral yellow spots and small and scattered dark spots, elliptic, similar in size to outer tepals, rounded at the apex; filaments yellow, 3–4 mm long, base slightly broad, anthers yellow, oblong, 6–7 mm long, ca. 1 mm wide, dehiscent by a narrow lateral fissure, circinnate after anthesis, connective yellow-orange; ovary green, oblong to clavate, 2–3 mm long, ca. 1.2 mm diameter, style yellowish, long obconic, to 12.8 mm long, 1.6–1.7 mm diameter at the apex, stylar branches yellow 2.6–3 mm long, bifid, spreading, moderately thickened, secondary branches subulate with apical stigmatic areas. Capsule not seen.

Ecological data:—Populations of Ainea conzattii var. macropetala are located only ± 75 km (straight line) NNW from those of the typical type variety ( Figure 1 ). The plants grow at elevations close to 2000 m a.s.l., on calcareous hills and bloom during the months of June and July. The climate in the region is semi-arid with an average temperature of 15.5°C, and an annual rainfall of 474.8 mm that is concentrated between May and October ( Servicio Meteorológico Nacional 2023). Vegetation corresponds to natural grasslands dominated by the genus Aristida Linnaeus (1753: 82) ( Cruz-Cisneros and Rzedowski 1980).

Conservation status:—The area where this variety grows is seriously threatened by the expansion of extensive pine afforestation under which the native grassland cannot develop. Assuming that this new variety is restricted to the calcareous temperate grasslands of northern Oaxaca, which cover about 50 km 2, and based on the rapid and extensive afforestation observed at the area ( Martorell et al. 2022), this new variety must be considered as Endangered according to IUCN’s criterion B2b (a shrinking area of occupancy <500 km 2, IUCN Standards and Petitions Committee 2022).

Etymology:—The name of the proposed new variety alludes to the inner tepals, which are similar in size and also in shape to the outer tepals.

Specimens examined of Ainea conzattii var. conzattii :— MEXICO. Oaxaca: DISTRICT of ETLA, Municipality of Santiago Tenango: a 1 km sobre la desviación a Santiago Tenango, carretera Oaxaca-Huajuapan, A. García-Mendoza & E. Martínez 4272 (MEXU), 1 km al N de la Carbonera, camino a Tenango, A. García-Mendoza et al. 7153 (MEXU, MO), 3 km al N de la Carbonera, camino a Tenango, A. García-Mendoza et al. 7157 (MEXU), 0.8 a 1.6 km de la brecha Carboneras-Santiago Tenango, A. Rodríguez 2948 (MEXU, UAMIZ); Municipality of San Juan del Estado, 10 km north of San Juan del Estado on the road towards San Miguel Aloapam, E. Norman 38 (ENCB). DISTRICT of JUXTLAHUACA, Municipality of San Juan Mixtepec, Yúu tzáan (Cañada de las Cazuelas), 5 km al SW de San Juan Mixtepec, A. García Mendoza and J. Reyes Santiago 5046 (MEXU), barrio Loma a 1.5 km al W de San Juan Mixtepec, J. Reyes Santiago 444 (MEXU (×2)), Yucu Shúun (Monte del Tesoro), a 16 km al S de San Juan Mixtepec, J. Reyes Santiago 882 (MEXU), Tres Cruces, a 16 km al NE de San Juan Mixtepec, J. Reyes Santiago 1653 (MEXU(×2), Yúu tzáan (Cañada de las Cazuelas), a 9 km al S de San Juan Mixtepec, J. Reyes Santiago 1935 (MEXU).

Figures

FIGURE 1. Map of known distribution of Ainea conzattii var. conzattii and Ainea conzattii var. macropetala.

FIGURE 2. A. Flower, front view of Ainea conzattii var. conzattii; B. C. Flower, front view of A. conzattii var. macropetala; D. Flower dorsal view of A. conzattii var. macropetala. Photo credits: A. Guadalupe Munguía; B., C., D. Carlos Martorell.

FIGURE 3. Holotype of Ainea conzattii var. macropetala. Photo credits: Bruno Téllez-Baños.