Diplusodon bahiensis T.B.Cavalcanti, 2011

Cavalcanti, Taciana B., 2011, New taxa in Diplusodon (Lythraceae) from Brazil, Phytotaxa 38, pp. 29-35 : 30-32

Diplusodon bahiensis T.B.Cavalcanti , sp. nov. ( Fig. 1 ).

Haec species nova Diplusodon hirsutus indumento et forma foliorum similis sed foliis et floribus maioribus, prophyllis longis, ultra apicem tubi floralis, epicalycum segmentis 2.5–3.0 mm longis et erectis differt.

Type:— BRAZIL. Bahia: Morro do Chapéu , 11º35’26” S, 41º12’26” W, 2 March 1997, Lughadha et al. 5955 (holotype CEN!, isotypes ALCB!, CETEC!, HUEFS!, K!, SPF!) .

Shrubs 1.0– 1.5 m tall, foliage congested. Upper branches cylindrical to subquadrangular, non-winged, hirtellous to rarely pubescent, trichomes white, thick and sparse, concentrated on the veins, internodes 1.0– 1.5 cm long. Petioles 1–3 mm long; leaf blades 10–22 × 5–13 mm, elliptic to ovate, base obtuse, apex obtuse, dark brown when dry, decussate, not imbricate, suberect, membranaceous, petiolate, not discolorous, eucamptodromous, margin revolute to subrevolute, sparse trichomes on both surfaces; secondary veins 3–5 on each side of midvein; acaro domatia type present. Inflorescence a compound raceme, frondose, congested; accessory branches absent, lateral branches 4–7 cm long; bracts similar to the vegetative leaves, smaller; flowers subsessile, hypopodium 1–2 mm long, epipodium 0.0– 0.5 mm long; prophylls 6.0–6.5 × 3–4 mm, reaching to the sinus between the sepals or to the apex of the sepal elliptic to narrow elliptic, unkeeled, apex obtuse, margin plane, white and sparse trichomes concentrated on the central vein and margin; floral tube 5.0– 5.5 mm long, light green when fresh, funnel-shaped, sparsely covered with white trichomes; sepals 2.5–3.0 mm long, narrowly triangular, ciliate, not caudate, not deflexed; epicalyx segments 2.5–3.0 mm long, lanceolate, flat, erect, shorter than sepals, ciliate; corolla 3.0– 3.5 cm in diam., lilac to rose-magenta, petals 12– 15 × 8.5–10.0 mm, oblong to elliptic, apex obtuse; stamens 12, free portion of the filaments 4.5–5.0 mm long, not exserted, pale yellow to lilac; ovary 2.0–2.1 × 1.9–2.0 mm, rhombic, glabrous, style 12.0– 12.5 mm long, rose, stigma green, ovules 17–26. Immature capsule 4.0–4.5 × 3–4 mm, oblong, glabrous; seeds not seen.

Distribution and ecology:— Known only from the state of Bahia (Chapada Diamantina), Brazil. Endemic to the vicinity of Morro do Chapéu, forming small populations along the roadsides in dry sandy soils of rocky outcrops and open fields at 1,000 –1,151 m. It flowers from January to May; immature fruits were collected from February to June.

Etymology:—Refers to the locality of all known collections of this species.

IUCN Red List category:— The species is known only in the vicinity of Morro do Chapéu. The conservation status of IUCN Red List is estimated as “VUD2” based on species that are vulnerable because of their very small populations or very restricted occupancy (typically less than 20 km ²) or number of locations (typically five or fewer), such that they are prone to the effects of human activities (microendemic species).

Paratypes:— BRAZIL. Bahia: Morro do Chapéu, BR-052, vizinhanças da ponte sobre o Rio Ferro Doido , ca. 18 km E de Morro do Chapéu, 17 June 1981 (fr), Mori & Boom 14509 (K) ; proximidades da Cachoeira do Ferro Doido , 11º37’31” S, 40º59’38” W, 20 April 2001 (fl, fr), Melo et al. 3342 ( CEN, HUEFS) ; 4 km de Morro do Chapéu, na estrada para Utinga , 11º34’45” S, 41º9’56” W, 26 March 1996 (fl), Stannard et al. 2561 ( HUEFS) ; 8 km SE da cidade de Morro do Chapéu , para o oeste da estrada para Utinga, 11 o 35' S, 41 o 12' W, 2 June 1980 (fr), Harley 23017 ( CEPEC) ; ca. 18 km E de Morro do Chapéu , 19 February 1971 (fl, fr), Irwin et al. 32618 ( NY) ; Morro das Pedras Duas Irmãs , 11º33’25” S, 41º17’50” W, 2 May 1999 (fl), França et al. 2845 ( CEN, HUEFS) ; 11º33’7” S, 41º17’17” W, 30 January 2003 (fl), França et al. 4131 ( HUEFS) ; estrada Morro do Chapéu-Bonito , km 12, 11º37’ S, 41º15’ W, 1 March 1989 (fl), Cavalcanti et al. 359 ( CEN) ; Torre Telebahia , ca. 6 km S de Morro do Chapéu, 16 June 1981 (fr), Mori & Boom 14453 (K, NY) ; Morrão, em torno da estação retransmissora da Telebahia, a ca. 6 km W da BA-046, entrando a ca. 1 km do entroncamento com a BA-052 ( Estrada do Feijão ), 14 March 1995 (fl), Queiroz & Nascimento 4258 ( CEPEC, K, HUEFS) ; 19,5 km SE da cidade de Morro do Chapéu , na estrada BA-052, 11 o 38' S, 41 o 2' W, 2 March 1977 (fl, fr), Harley 19230 (K n.v., CEPEC) ; 16 km NW de Lagoinha 4 March 1974 (fl, fr) Harley 16697 ( CEPEC, NY n.v.) ; 16 km NW de Lagoinha, 5,5 km SW de Delfino, na estrada para Minas do Mimoso , 10 o 22' S, 41 o 20' W, 8 March 1974 (fl, fr), Harley et al. 17006 ( CEPEC, MO, NY, SPF) ; Umburanas, Serra do Curral Feio ( Serra da Empreitada ), entrando ca. 20 km S de Delfino, 41º19’ S, 10º22’ W, 9 April 1999 (fl, fr), Queiróz et al. 5197 ( HUEFS) .

Discussion:— Diplusodon bahiensis is similar to the vegetatively variable and widespread D. hirsutus . However, D. hirsutus is well defined by its short (2.5–4.0 mm long), obovate, keeled prophylls, floral tube 2.0– 2.5 mm long, and epicalyx segments 0.5–3.0 mm long, that are spreading to slightly deflexed. This new species has larger flowers, with floral tube 5.0– 5.5 mm long, long-acuminate sepals (2.5–3.0 mm long), erect and longer epicalyx segments (2.5–3.0 mm long), and prophylls reaching or surpassing the floral tube apex. The flowers have sparse trichomes and are not hirsute as in D. hirsutus .

Figures

FIGURE 1. Diplusodon bahiensis. A. branch with inflorescences. B. leaf, abaxial surface. C. prophyll, adaxial surface. D. flower with prophyll, without petals and stamens. (A from Lughadha et al. 5955; B from Cavalcanti et al. 359; C, D from Queiróz et al. 5197). Illustrated and inked by Taciana Cavalcanti.