Cuphea praetermissa M.G.Facco & T.B.Cavalcanti, 2023

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

17. Cuphea praetermissa M.G.Facco & T.B.Cavalcanti , sp. nov.

Type:— BRAZIL. Tocantins: Taipas do Tocantins, estrada entre Dianópolis e Taipas , 12°10’03”S, 46°57’26”W, 15 January 2008, Pastore, Harley & Suganuma 2439 (holotype CEN [00069269]!, isotype HUEFS [2 sheets]!) . Figs. 14A–G , 21 .

Diagnosis:— Cuphea praetermissa morphologically resembles C. carajasensis and C. tenuissima , classified in C. sect. Trispermum s.l., but differs mainly by leaves 3–4(–5)-verticillate at midstem, opposite distally (vs. uniformly opposite in C. carajasensis and C. tenuissima ), with margins strongly revolute to the midvein (vs. plane to subrevolute in C. carajasensis ), larger and robust floral tubes, (6–) 7–8 mm long (vs. smaller and slender floral tubes, 4–6.7 mm long, in C. tenuissima ), staminal filaments free in the upper third of the floral tube, five antesepalous exserted, four antepetalous included (vs. staminal filaments free in the middle third of the floral tube and fully included in C. tenuissima ), and ovary slightly pilose to glabrous (vs. dorsal region of the ovary densely villous in C. carajasensis ).

Subshrubs 15–50 cm tall;stems erect, indumentum strigose, one-armed trichomes, sometimes glandular trichomes, 0.5–0.8 mm long, and eglandular trichomes with curved apices present; internodes 0.5–3 cm long; brachyblasts absent. Leaves 3–4(–5)-verticillate at midstem, opposite distally, rarely subalternate or uniformly opposite, sessile to petiolate, petiole ca. 1 mm long, blades 7–40 × 0.5–2 mm, linear, rarely narrow-ovate, apex acute, base obtuse to truncate, margin strongly revolute to the midvein, indumentum strigose on both surfaces, with one-armed trichomes, sometimes glandular trichomes present, rarely glabrescent; hyphodromous, main vein prominent on abaxial face. Racemes 4–15 cm long, bracteose, simple to compound, elongated, distinct; bracts 1.2–13(–34) × 0.3–1.5 mm, subequal pairs, narrowovate to linear, similar to leaves in indumentum. Flowers alternate to opposite; pedicels 2–5(–7) mm long; bracteoles 0.4–0.9 mm long, ovate to broad-ovate; floral tubes (6–) 7–8 mm long; spur obtuse to galeate, deflexed; outer surface vinaceous in dorsal region, green ventrally, indumentum strigose, sometimes erect eglandular and glandular trichomes present; inner surface villous behind stamens, pilose around ovary; petals 6, dark pink to lilac, subequal, two dorsal 3.7–4.6 × 1.2–1.8 mm, narrow-elliptic to narrow-obovate, four ventral 3.3–5 × 1–1.9 mm, narrow-elliptic to narrowobovate; stamens free in the upper third of the floral tube, five antesepalous exserted, four antepetalous included; pistil 3.5–4 mm long; ovary slightly pilose to glabrous; style slightly pilose to glabrous; ovules 3; nectary ca. 1 × 0.8 mm, deflexed. Seeds 2–3, 1.6–2.2 × 1.3–2 mm, obovate, elliptic to suborbicular, apex obtuse to slightly retuse, base acute to obtuse, margin obtuse.

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

Distribution and habitat: — Brazil, in Maranh ã o and Tocantins states ( Fig. 21 ); “campo limpo”, “campo sujo”, “campo úmido”, and “cerrad ã o”; 450–900 m elev.

Conservation status: — Cuphea praetermissa was categorized as Endangered (EN) B2ab(i,ii,iii), presenting EOO of 63,113 km ² and AOO of 44 km ². The region where the species occurs, known as Matopiba (the new agricultural frontier of Brazil; Alencar et al. 2020), has large soybean plantations and other monocultures, with the potential to advance into new areas, reducing the EOO, AOO, and the quality of the habitat.

Etymology: —From the Latin, “ praetermissus ” means neglected, that went unnoticed, in reference to the specimens belonging to C. praetermissa that were identified as C. tenuissima , due to the great morphological similarity.

Paratypes: —BRAZIL. Maranhão: Balsas, Projeto Geral de Balsas, 07º35’00”S, 46º05’00”W, 21 March 1997, Oliveira et al. 715 (CEN!, FURB!, HEPH!). Tocantins: Almas, rodovia entre Almas e Natividade, estrada de terra com entrada em frente à 1ª entrada para a cidade de Almas, estrada para a fazenda Diamantina, pé da Serra Negra, 11º24’37”S, 47º08’17”W, 16 January 2008, Pastore et al. 2455 (CEN!); Dianópolis, ca. de 4 km da cidade na estrada para Almas, 11 February 1987, Pirani et al. 1913 (CEN!, K image!, SPF!); Dianópolis, rodovia Almas-Dianópolis, a 4 km antes de Dianópolis, 11º36’08”S, 46º51’27”W, 08 April 1997, Cavalcanti et al. 2241 (CEN!); Dianópolis, TO-040 entre Novo Jardim e Dianópolis, à cerca de 8 km de Dianópolis, 11º39’40”S, 46º45’22”W, 28 January 2003, Cavalcanti et al. 3145 (CEN!); Dianópolis, estrada da divisa BA/TO para Dianópolis, à cerca de 9 km da entrada da cidade de Dianópolis, 11º37’45”S, 46º46’51”W, 28 January 2014, Walter et al. 6669 (CEN!, UB!); Natividade, rodovia BR-010, caminho para Natividade, 12º01’53”S, 47º29’28”W, 26 March 2011, Bringel-Jr. & Moreira 709 (CEN!, UB!); Natividade, estrada Natividade-Almas, estradinha de terra à direita, à cerca de 17.5 km de Natividade, 11º41’41”S, 47º38’53”W, 29 January 2014, Walter et al. 6690 (CEN!, UB!); Paraíso do Tocantins, north side of city of Paraíso do Norte de Goiás, 10º10’00”S, 48º53’00”W, 28 December 1969, Eiten & Eiten 10080 (K image!, NY image!); Paran ã, estrada Palmeirópolis-Alvorada de Goiás, à 25 km de Palmeirópolis, 12º54’46”S, 48º33’42”W, 06 April 1997, Cavalcanti et al. 2231 (CEN!); Pindorama [do Tocantins], 01 January 1966, Belém 2035 (CEPEC!, P image!, UB!); Ponte Alta do Tocantins, estrada Ponte Alta do Tocantins-Rio da Conceiç ã o, próximo à fazenda do Sr. Luis Piriquito, 10º59’08”S, 47º11’04”W, 29 January 2015, Antar et al. 708 (CEN!, SPF!); Taguatinga, na subida da Serra que faz divisa com a Bahia, a 10 km do entroncamento para Dianápolis, Espig ã o Mestre, 12º20’43”S, 46º20’16”W, 09 April 1997, Cavalcanti et al. 2338 (CEN!).

Cuphea praetermissa is identified by the linear leaves, 3–4(–5)-verticillate at midstem, opposite distally, hyphodromous ( Fig. 14B ), with margins strongly revolute to the midvein ( Fig. 14C ), and by the distinct, bracteose racemes ( Fig. 14A ). It is a species restricted to the Brazilian Cerrado, occurring in southern Maranh ã o state and southeastern Tocantins.

Cuphea praetermissa is morphologically similar to C. tenuissima , which can be distinguished by the uniformly opposite leaves, the smaller and slender floral tubes, 4–6.7 mm long, with staminal filaments free in the middle third of the floral tube, fully included ( Fig. 16E ). In C. praetermissa , the leaves are 3–4(–5)-verticillate at midstem, the floral tubes are larger and more robust, (6–) 7–8 mm long, and the staminal filaments are free in the upper third of the floral tube, five antesepalous exserted, four antepetalous included ( Fig. 14E ). Cuphea praetermissa is also similar to C. carajasensis , endemic to the Pará state. However, this species has uniformly opposite leaves, with a plane to subrevolute margin, and the dorsal region of the ovary is densely villous.

Cuphea praetermissa presents the remarkable characteristics of this section, such as the deflexed nectary at the base of the ovary ( Fig. 14F ), 3 ovules, obtuse margin seeds ( Fig. 14G ), and pollen grains with thickened exine between the pores. Ongoing molecular phylogenetic analyses confirm C. praetermissa as a distinct species belonging to C. sect. Trispermum (Facco, unpublished data).

Figures

FIGURE 14. A–G. Cuphea praetermissa. A. Habit; B. Detail of 3-verticillate leaves; C. Abaxial surface of the leaf, margin strongly revolute to the midvein; D. Floral tube in lateral view, without petals; E. Floral tube in longitudinal-dorsal section, without petals; F. Pistil; G. Seed. H–N. Cuphea pulchra var. pulchra. H. Habit; I. Detail of a branch; J. Contracted raceme at the apex of the branch; K. Floral tube in lateral view; L. Floral tube in longitudinal-dorsal section; M. Pistil; N. Seed.A–D, G: Pastore et al. 2455; E: Bringel-Jr. & Moreira 709; F: Pastore et al. 2439; H–J, L–N: Facco et al. 487; K: Miranda & Conceição 682. Scale bar. A: 5 cm; B: 5 mm; C: 0.5 mm; D–F, N: 2 mm; G: 1 mm; K: 3 mm; L–M: 6 mm.

FIGURE 16. A–G. Cuphea tenuissima. A. Branches with flowers; B.Abaxial surface of the leaf, margin strongly revolute to the midvein; C. Detail of raceme; D. Floral tube in lateral view, without petals; E. Floral tube in longitudinal-dorsal section, without petals; F. Pistil; G. Seed.A, C: Simon et al. 2699; B: Silva et al. 28; D–E: Cavalcanti et al. 2263; F: Pereira-Silva & Moreira 14958; G: Lima et al. 66. Scale bar. B, F, G: 1 mm; D–E: 2 mm. Photos. A, C: Marcelo Simon.

FIGURE 21. Geographical distribution of Cuphea bahiensis, Cuphea cunninghamiifolia, Cuphea laricoides and Cuphea praetermissa.