Cuphea inaequalifolia Koehne (1877: 286)

Facco, Marlon Garlet & Cavalcanti, Taciana Barbosa, 2023, Taxonomic Revision of Cuphea sect. Trispermum s. l. (Lythraceae), Phytotaxa 588 (1), pp. 1921-1935 : 1921-1935

12. Cuphea inaequalifolia Koehne (1877: 286) .

Type :— BRAZIL. “Habitat in Brasilia occidentali”, Tamberlik s.n. (holotype W [0022510] image!). Figs. 11G–M , 20 .

Subshrubs 30–100 cm tall; stems erect to decumbent, indumentum hirsute and strigose, glandular trichomes 2–4 mm long, vinaceous, and one-armed trichomes, mixed with short eglandular trichomes, <1 mm long, with curved apices; internodes 1–4 cm long; brachyblasts absent. Leaves opposite, rarely 3-verticulate, chartaceous, petioles 1–2 mm long, blades 15–60 × 7–15 mm, narrow-ovate to oblong, apex acute, base obtuse to subcordate, margin subrevolute, glandular-ciliate, indumentum strigose and sparsely hirsute on both surfaces; brochidodromous. Racemes 10–15 cm long, frondose-bracteose, simple to compound, elongated, indistinct; bracts 3–25 × 1.5–6 mm, strongly unequal along the inflorescence, one of the bracts of the pair much smaller in size, elliptic, similar to leaves in indumentum. Flowers alternate, fasciculate on young branches; pedicels 1.5–3 mm long; bracteoles 0.4–0.7 mm long, suborbicular to broadovate; floral tubes 6–7 mm long; spur obtuse, deflexed; outer surface vinaceous on the dorsal region, green ventrally, indumentum pubescent and densely glandular, one-armed appressed trichomes over the sepals; inner surface villous behind the stamens, slightly pilose on the dorsal veins and ovary region; petals 6, light pink, subequal, two dorsal 3.5–4.2 × 1.7–1.8 mm, elliptic to obovate, four ventral 4.8–5.2 × 1.7–2 mm, elliptic to narrow-obovate; stamens free in the upper third or middle third of the floral tube, included to exserted; pistil 3.2–6 mm long; ovary glabrous; style glabrous; ovules 3; nectary ca. 0.8 × 0.8, deflexed. Seeds 2–3, 1.8–2.1 × 1.7–1.9 mm, obovate to broad-obovate, apex obtuse, base slightly acute, margin obtuse.

Phenology: —Collected with flowers and fruits from October to April.

Distribution and habitat: — Brazil, in the states of Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Rondônia, and S ã o Paulo, and Paraguay, in the departments of Amambay and Canindeyú ( Fig. 20 ) ( Lourteig 1987 , Rodas & Briones 2010); “campo limpo”, and cerrado sensu stricto; 110–850 m elev.

Conservation status: — Cuphea inaequalifolia was categorized as Least Concern (LC) due to its wide geographic distribution.

Representative specimens examined: —BRAZIL. Goiás: Cachoeira de Goiás, Fazenda Biquinha, estrada Cachoeira de Goiás-Aurilândia, km 5, próximo à vereda da sede, 10 January 1982, Pereira-Silva 4183 (CEN!); Mineiros, Parque das Emas, localizada próxima à sede do parque, 05 January 1995, Viana et al. 2 (CEN!); Paraúna, Serra das Galés, 14 March 1989, Cavalcanti et al. 429 (CEN!). Mato Grosso: Barra do Garças, Serra do Roncador, 15º20’59”S, 52º13’50”W, 04 April 2018, Pereira-Silva et al. 17024 (CEN!); Canarana, BR-158, Água Boa-Ribeir ã o Cascalheira, Km 57, 13º37’11”S, 51º56’52”W, 05 April 2018, Pereira-Silva et al. 17056 (CEN!); Pedra Preta, BR-364, a 42,8 km ao sul de Pedra Preta, Serra da Petrovina, 16º47’58”S, 54º10’17”W, 08 April 2018, Pereira-Silva et al. 17088 (CEN!); Ribeir ã o Cascalheira, Km 262, Xavantina-Cachimbo road, 51º46’00”W, 12º49’00”S, 04 January 1968, Philcox & Ferreira 3877 (IAN!, NY image!). Mato Grosso do Sul: Aquidauana, Serra de Maracaju, Estaç ã o Repetidora da TELEMS, 05 February 1988, Ribas & Pereira 2550 (CEN!); Corumbá, Fazenda Sagrado, pantanal da Nhecolândia, 08 October 1976, Allem 199 (CEN!). Minas Gerais: Uberlândia, Clube Caça e Pesca, Itororó, 05 February 1999, Barbosa & Amaral 1961 (HUFU!). Rondônia: Porto Velho, BR-364, entrada para o transecto Caiçara, módulo 4, 09º28’25”S, 64º46’00”W, 08 February 2012, Pereira-Silva et al. 16025 (CEN!). São Paulo: Botucatu, 18 km north of Botucatu (14 km east of S ã o Manuel), along the S. Manuel-Piracicaba highway, near ex-RR station, 13 de Maio, 22°45’S, 48°25’W, 31 December 1970, Gottsberger 21R-311270 (P image!). PARAGUAY. Canindeyú: Reserva Natural del Bosque Mbaracayú, Ñandurokai (rumbo), 15 March 1997, Jiménez et al. 1840 (BM image!); Reserva Natural del Bosque Mbaracayú, Aguará-Ñú, 05 December 1997, Jiménez & Marín 1998BJ (BM image!).

Cuphea inaequalifolia is recognized by the unequal pairs of bracts along the inflorescence, with one of the bracts of the pair much smaller in size ( Fig. 11H ). It occurs in central and western Brazil, where almost all records are located, and in southeastern Paraguay, in grasslands and “cerrados”.

Cuphea inaequalifolia is the only species of C. sect. Trispermum s.l. that presents populations with variations in the position of the stamens, with filaments free in the upper third of the floral tube, exserted, or in the middle third, included. In the latter case, it can be confused with C. micrantha . Besides the unequal pairs of bracts, C. inaequalifolia differs from C. micrantha by the strigose indumentum on the branches, with one-armed trichomes. It is also morphologically similar to C. antisyphilitica , but in this species the bracts are not reduced. Ongoing molecular phylogenetic analyses confirm C. inaequalifolia as a distinct species (Cavalcanti, pers. comm.).

Koehne (1877) mentioned only the collection “ Tamberlik s.n. ” in the description of C. inaequalifolia . Since no duplicates were found, Lourteig (1987) correctly indicated the specimen deposited in W (0022510) as the “ holotype ”. Years later, C. inaequalifolia was unnecessarily lectotypified under the same specimen by Duré & Molero (2000).

Figures

FIGURE 11. A–F. Cuphea gracilis. A. Habit; B. Detail of branches; C. Floral tube in lateral view, without petals; D. Floral tube in longitudinal-dorsal section, without petals; E. Pistil; F. Seed. G–M. Cuphea inaequalifolia. G. Habit; H. Inflorescence branch; I. Flower in lateral view; J. Floral tube in lateral view, without petals; K. Floral tube in longitudinal-dorsal section, without petals; L. Pistil; M. Seed. A, B, E: Steyermark et al. 131594; C, D, F: Davidse & Miller 26439; G, I: Pereira-Silva et al. 17024; H, J–M: Pereira-Silva et al. 17088. Scale bar.A: 5 cm; C, D, L: 2 mm; E, F, M: 1 mm; J–K: 3 mm.

FIGURE 20. Geographical distribution of Cuphea auriflora, Cuphea inaequalifolia and Cuphea tenuissima.