Diplusodon xiphodon T.B. Cavalc., 2015

Cavalcanti, Taciana B., 2015, New species in Diplusodon (Lythraceae) from Brazil, Phytotaxa 226 (2), pp. 144-156 : 155

6. Diplusodon xiphodon T.B. Cavalc. , sp. nov.

Type:— BRAZIL. Bahia: Mucugê, Vale do Medronho, 13º1’ S, 41º21’ W, 2 March 2009 (fl., fr.), Harley & Ribeiro, Jr. 55896 (holotype, HUEFS!). Figure 7 .

Shrubs, foliage lax. Upper branches cylindrical, unwinged, hirtellous, trichomes white, thick and sparse, internodes 1.5–4.5 cm long. Leaves decussate, not imbricate, patent to suberect, coriaceous, petiolate, slightly discolorous, dark brown when dry, acrodromous with supranumerary base to eucamptodromous; petiole 1–2 mm long; blades 10–20 × 7–15 mm, orbicular to ovate, base obtuse to retuse, apex obtuse, margin subrevolute, hirtellous on both surfaces, adaxial surface gray-colored, abaxial surface rust-colored; veins 3 or 4 on each side along the midvein; domatia present, inconspicuous. Synflorescence bracteose, diplobotryum to triplobotryum type, lax; accessory branches absent, principal florescence ca. 9 cm long, paraclades 4–9 cm long, delicate; bracts 4–12 × 3–10 mm, orbicular; flowers subsessile, hypopodium ca. 1 mm long, epipodium 0–0.5 mm long; prophylls ca. 3.5 × 2 mm, reaching the middle of the floral tube, clavate to spathulate, unkeeled, apex obtuse, margin plane, with sparse, white, thick trichomes, strongly ciliate with thick trichomes; floral tube ca. 3.5 mm long, funnel-shaped with an attenuate base, sparsely covered with white, thick trichomes; sepals ca. 2 mm long, triangular, ciliate, slightly caudate, apex deflexed; epicalyx segments ca. 2 mm long, sword shape, flat, spreading, slightly shorter than sepals, glabrous, strongly ciliate with thick trichomes; corolla ca. 1.5 cm in diam., dark rose, petals ca. 6 × 4 mm, elliptic, apex obtuse; stamens 12, free portion of filaments ca. 7 mm long, exserted ca. 2 mm; ovary ca. 2 × 2 mm, slightly rhomboid, glabrous, style 9–10 mm long, ovules ca. 7. Capsules 4.5–5 × 3–3.5 mm, elliptic-fusiform, slightly stipitate, glabrous; seeds 5 or 6, 2.8–3 × 1.8–2 mm.

Distribution and ecology:—Known only from Mucugê, Bahia (Chapada Diamantina), growing in rocky-sandy soil. Flowers and fruits in March.

Etimology:—Specific epithet related to the sword-shaped epicalyx segments.

Paratype:— BRAZIL. Bahia: Rio de Contas, vertente leste, Campo do Queiróz, ao lado leste, 13º32’ S, 41º57’ W, 29 November 1988 (fl., fr.), Harley 26681 ( CEN [2]!, CEPEC!, K!, SPF!).

Comments:— Diplusodon xiphodon is characterized by orbicular to ovate and slightly discolored leaves, delicate bracteose inflorescence with small flowers and orbicular bracts. Is similar to D. bahiensis T. B. Cavalcanti (2011: 30) because of its dark brown leaves when dry, hirtellous leaves and flowers and number leaf veins. The species differ mainly by D. bahiensis having frondose and congested inflorescence, with thick branches, larger flowers (floral tube 5–5.5 mm long) and prophylls longer (6–6.5 mm long), reaching the apex of the floral tube or surpassing it until the base of the epicalyx segments.

Figures

FIGURE 7. Diplusodon xiphodon (A–F from Harley & Ribeiro, Jr. 55896). A, branch with inflorescences. B, leaf, abaxial surface. C, flower with prophyll, without petals. D, prophyll, adaxial surface. E, epicalyx segment. F. capsule.