Cuphea vazquezii Padilla-Lepe, 2024

Cuphea vazquezii Padilla-Lepe View in CoL , sp. nov. ( Figs. 1–3 View FIGURE 1 View FIGURE 2 View FIGURE 3 .)

Type:— MÉXICO: Colima, Comala, Cerro Grande , brecha de Campo Cuatro a Lagunitas , 1600 m, on limestone karst topography with tropical dry forest, 12 October 2023 (fl.), J. Antonio Vázquez-García & Jesús Padilla-Lepe 10308 (holotype IBUG!; isotypes: MO!, WIS!, ZEA!) .

Diagnosis:— Cuphea vazquezii shares with C. mimuloides its annual habit, size of the non-bicolored and spurred floral tubes, deflexed nectariferous disks, and stamens included in the floral tubes. However, it differs from the latter in having a habit none-rhizomatous (vs. rhizomatous); leaves and flowers mostly alternate (vs. mostly opposite); leaf blades larger, 11.0–75.0 × 3.0–19.0 mm (vs. 10.0– 15.0 × 3.0–10.0 mm); pedicels shorter, 2.0–3.0 mm (vs. 5.0–9.0 mm); mature floral tubes narrowly tubular, widest at its proximal ¼ and softly constricted below the mouth (vs. bottle-like, widest near the middle and strongly constricted below the mouth); spur present vs. absent; petals 2, yellow (vs. 6, white to pink); nectariferous disc deflexed (vs. non-deflexed); seeds 3 and smaller, 1.75–1.80 × 1.5–1.6 mm (vs. numerous and 0.5 × 0.3 mm). Cuphea vazquezii is also similar to C. michoacana in having a similar annual and none-rhizomatous habit, leaf size, deflexed nectariferous disk, number and color of petals, and stamens included in the floral tubes. However, it differs from the latter in having leaves and flowers mostly alternate (vs. mostly opposite); mature floral tubes narrowly tubular, 4.5–5.5 × 1.2–1.4 mm, widest at its proximal ¼ and softly constricted below the mouth and non-bicolored (vs. conical, 5.6–6.6 × 1.9–2.7 mm, widest at the distal ¼ of its length, unconstricted, slightly narrowing near the mouth and sharply bicolored); seeds 3 and smaller, 1.75–1.80 × 1.5–1.6 mm (vs. 2–3 and 2.0 × 2.0).

Description:—Annual herbs, 10.0–41.0 cm, non-rhizomatous, stems sparsely branched at or near the stem apex, the branches to 20.0 cm long; stems 1.0–2.0 mm, stem and branches brownish red, sparsely to moderately minutely hirsute, the hairs white, curved, antrorsely oriented; glabrescent. Leaves mostly alternate; leaf blades (11.0–)45.0–75.0 × (3.0–19.0) mm, simple, lanceolate, translucid glands throughout, cuneate at the base, acute at the apex, the margin slightly crenate to dentate, yellowish-green on the upper side, lighter on the underside with curved secondary veins with translucent trichomes; pedicel 2.0–3.0 mm. Mature floral tubes 4.5–5.5 × 1.2–1.4 mm at anthesis, narrowly tubular, widest at the proximal ¼ of its length and softly constricted below the mouth; including a conspicuous spur extending 2.0–3.0 mm beyond the attachment of the pedicel, reddish only at the very tip; the neck of the floral tube slightly contracted at anthesis and in fruit, mouth 1.5–2.0 mm wide in lateral view; outer surface greenish throughout (non-bicolored), green at the veins, yellowish green between veins, with trichomes globose, sessile and glandular; glabrous inside the floral tube. Petals 2, narrowly obovate, 2.0–2.1 × 0.8–0.9 mm, bright yellow. Stamens 11, two shorter and inserted deepest, the filaments glabrous, the other 9 gathered toward the ventral side of the tube, the filaments glabrous. Style glabrous, stigma capitate, ovules 3, placenta erect at dehiscence, pale green, with three seeds. Nectary disc at the base of the ovary 0.60–0.62 × 0.25–0.27 mm, deflexed and extended into the spur, narrowly oblong, creamy white. Seeds 3, 1.75–1.80 × 1.5–1.6 mm, suborbicular, starting green, turning brown at maturity.

Distribution, habitat and phenology:—Known only from the type, from the eastern limestone flanks of the karstic Cerro Grande massif in the Sierra de Manantlán Biosphere Reserve, Comala, Colima, Mexico. On tropical dry forest gaps, on calcareous rocks with tropical dry forest with Bursera spp. Flowering from early October to November and fruiting from late October to December.

Eponymy:—The specific epithet honors Dr. José Antonio Vázquez-García from the Botanical Institute at the University of Guadalajara-CUCBA-Zapopan, Jalisco, plant systematist, ecologist and conservationist, co-discoverer of this species, who has devoted over four decades to the study and conservation of the flora and vegetation of the Sierra de Manantlán in Western Mexico, including Cerro Grande where this species was discovered (Vázquez-García 1995, Vázquez-García & Givnish 1998, 2000, Vázquez-García et al. 1995) and contributed to its establishment as a MaB-UNESCO Biosphere Reserve and to the foundation of the ZEA herbarium and the Scientific Station Las Joyas of University of Guadalajara-CUCSUR-Autlán, Jalisco.

Conservation status: —We assessed the new species as critically endangered (CR) based on the criteria B1ab from IUCN (2019). The Extent of Occurrence was 0.6 km 2 and the Area of Occupancy was 0.4 km 2. A population reduction is expected due to deforestation from forest conversion to pasturelands, extensive cattle foraging, firewood extraction, and climate change, which could cause more severe natural disasters and alter the microclimate of this fragile habitat. Also, the species is known from a single population within an area of ca. 0.6 km 2.

Paratypes:— MÉXICO: Colima, Comala, Cerro Grande, brecha de Campo Cuatro a Lagunitas , 1550 m, 8 October 2023 (fl), Vázquez-García & Padilla-Lepe 10292 ( IBUG, CIMI!) ; 1500 m, 12 October 2023 (fl. & fr.), Vázquez-García & Padilla-Lepe 10309 ( IBUG!, IEB!) .