Amorimia candidae R.F.Almeida, 2016

Almeida, Rafael Felipe De, Berg, Cássio Van Den & Amorim, André Márcio Araujo, 2016, Untangling the Amorimia rigida complex, a puzzling group of lianescent Malpighiaceae from Eastern Brazil, Phytotaxa 284 (1), pp. 1-23 : 8-13

2. Amorimia candidae R.F.Almeida , sp.nov. ( Figs. 2–3 , 11–12 )

Type: — BRAZIL. Bahia: Mun. Itaberaba, margens da Rodovia BR 242, 16 July 2013, fl. fr., R.F. Almeida, M. Alves, L.M.M. Conti, E.C. Chagas & C.F. Hall 594 (Holotype: HUEFS!; isotypes: CEPEC!, MICH!, NY!, P!, RB!, US!).

Differs from Amorimia rigida by its conduplicate leaf blades with mucronate, rounded to retuse apex; leaves associated to the inflorescence elliptic to orbicular; secondary veins 5–7; peduncles shorter; petals golden yellow turning red at post-anthesis; stamens opposite to petals longer than those opposite to sepals; samaras whitish to reddish; dorsal wing of samaras obtrapezoidal with rounded angles.

Woody vines to scandent shrubs; stems sparsely sericeous-velutine to glabrous at age; stipules 0.4–0.5 mm long, triangular, epipetiolar, persistent to deciduous. Leaves decussate, reduced in inflorescences; petioles 2–5 mm long, sparsely sericeous-velutine to glabrous, eglandular at apex; leaf blades 3–7.7 × 1.8–4.4 cm, conduplicate, not bullate, ovate, wide-elliptic to orbicular (frequently when associated to the inflorescence), base cordate to rounded, margin revolute, apex mucronate, rounded to retuse, both sides glabrous, 1–2 pairs of glands near base or up to 3 mm of margins on the distal half, 0.4–0.5 mm diam.; midvein adaxially impressed, abaxially prominent, 5–7 pairs of secondary veins, abaxially reddish, prominent, arching 22–24°, subopposite to alternate, reticulum prominent on both sides. Thyrses (pseudoracemes) or panicles, axillary; main axis 5–24 cm long, striated, sericeous–velutine; cincinni 28–32, 1-flowered, decussate; bracts 3.5–4 × 1.5–2 mm, ovate to elliptic (sometimes leaf-like), sessile, parallel to peduncle, 1 pair of glands at base, sericeous-velutine on both sides; peduncle 1–1.5 × 0.9–1 mm, sericeous-velutine; bracteoles 1.5–2 × 1.4–1.5 mm, elliptic, inserted at the apex of peduncles, parallel to the pedicel, eglandular, both sides sericeous-velutine; pedicels 3.5–4 × 0.9–1 mm, sericeous-velutine. Flowers 9–11 mm diam. at anthesis; floral buds 3.5–4.5 × 3.5–4 mm. Sepals 1.8–2 × 1–1.5 mm, ovate, appressed to the androecium, apex obtuse to rounded, plane at anthesis, both sides sericeous-velutine; glands yellow turning orange to dark-orange at age, 1.8–2 × 0.7–0.8 mm. Petals golden yellow turning red at age, margin sinuate; lateral petals patent at anthesis, anterior-lateral petals overlapping at anthesis, limb 4.5–5 × 3–3.5 mm, elliptic to obovate, truncate at base, adaxially sericeous-velutine distally, abaxially sericeous-velutine, claws 1.4–1.5 × 0.4–0.5 mm, adaxially glabrous, abaxially sericeous-velutine; posterior petal erect at anthesis, limb 4–4.2 × 3.4–3.5 mm, elliptic, truncate at base, 1-pair of red glands at base, adaxially sericeous-velutine distally, abaxially sericeous-velutine, claw 2.3–2.5 × 0.70–0.75 mm, adaxially glabrous, abaxially sericeous-velutine. Stamens 10, those opposite petals longer than those opposite sepals; filaments 2.25–2.5 × 0.25–0.5 mm, connate 0.9–1 mm long at base, glabrous; anthers heteromorphic, those opposite sepals elliptic, those opposite petals obovate, 1–1.25 × 0.5– 0.6 mm, reflexed at anthesis, base, connective and apex pubescent. Ovary 1.3–1.5 × 1.3–1.5 mm, each carpel with primordial lateral and dorsal wings, sericeous-velutine; styles 3, cylindrical at base and apex, parallel at base, diverging at middle, apex truncate with apiculate angle, rarely geniculate, sericeous-velutine at base, anterior style 1.1–1.25 mm long, posterior styles 1.4–1.5 mm long; stigma lateral, discoid. Samaras whitish to reddish in vivo; dorsal wing 6–7 × 3–3.25 mm, obtrapezoidal with rounded angles, margin sinuate, sericeous-velutine on both sides; lateral wings 1.7–2.5 × 1.6–2 cm, flabellate, margin sinuate, upper angle 20°, lower angle 25° from the nut, sparsely sericeous-velutine on both sides; nut ovoid, sericeous-velutine; areole 4.5–5 × 2–2.2 mm, elliptic. Seeds 3.6–4 × 2–2.25 mm, testa rugose; embryo ovoid, cotyledons folded.

Additional specimens analyzed (paratypes): — BRAZIL. Bahia: Mun. Ibiquera, January 1980, fr., Pinto 05-1980 (CEPEC, FLOR, HRB); Mun. Itaberaba, pastagem, S12°28’ W40°18’, 15 October. 2002, fl., Moura 3 (HUEFS); loc. cit., Fazenda Morro da Pedra, 15 July 1982, fl., Bastos 266 (CEPEC, HUEFS, IPA); loc. cit. Fazenda Itaberaba, morro de Itaberaba, sítio com pinturas, S12°29’57’’ W40°04’56’’, 5 June 2005, fr., Melo 3936 (CEPEC, HUEFS); loc. cit., margens do Paraguaçu, June 1973, fl., Pinto s.n. (ALCB1929); Mun. Milagres, caatinga arbustiva, September 2009, fl., Brito 23 (HUEFS); loc. cit., caatinga arbustiva, December 2009, fl., Brito 28 (HUEFS); loc. cit., BR-116, embaixo da ponte, 19 August 2015, fr., Aona 4208 (HUEFS, HURB); Mun. Rafael Jambeiro, Fazenda Coqueiro Rosarinho, km 29 road BR-242, 2 July 2002, fl., Santos s.n. (CEPEC, HUEFS64423); Mun. Santa Terezinha, Serra da Jibóia, S12°47’46’’ W39°31’37’’, 303 m, 9 October. 2010, fl., Melo 8557 (HUEFS). loc. cit., S12°47’46’’ W39°31’37’’, 303 m, 9 October 2010, fl., Melo 8563 (HUEFS); loc. cit., May 1999, fl., Pinto s.n. (ALCB17936); loc. cit., Serra do Leão, Fazenda Limeira, 12 February 2016, fr., Costa 1630 (HURB);

Distribution, habitat and phenology: — Amorimia candidae is known only from SDTF within Caatinga vegetation in Bahia state, Brazil ( Fig. 12 ), flowering from May to July, and fruiting from January to February and August.

Conservation status: — Amorimia candidae is represented by only few records, restricted to five municipalities, within an area of occurrence of approximately 20.000 km ² in anthropomorphically modified Caatinga vegetation. Thus, this species should be regarded as Endangered (categories B1a and B1b), due to its range of distribution being less than 100 km ² and continually declining habitat quality.

Etymology: —The epithet honors the Brazilian botanist Dr. Maria Candida Henrique Mamede (b. 1956), colleague, former advisor, and longtime contributor in the studies of Brazilian Malpighiaceae .

Taxonomy notes: — Amorimia candidae resembles A. rigida on indumenta type, inflorescence morphology, sepal shape, position of petals at anthesis, anthers indumenta and shape of the apex of style, but differs on position and shape of the leaves, petal morphology, size of the filaments and shape of the dorsal wings of the samaras.A list of informative characters to differentiate them is presented on Table 1.

Figures

FIGURE 2. Amorimia candidae R.F.Almeida: A. flowering branch; B. conduplicate leaf; C. mature inflorescence showing a detail of a bract (arrow); D. floral bud in side view; E. floral bud in frontal view; F. flower in frontal view; G. detail of dorsal wing of samaras (arrow); H. samara in dorsal view; I. Seasonally Dry Forest in Central Bahia state (photographs by R.F. Almeida).

FIGURE 3. Amorimia andersonii R.F.Almeida (based on L.C. Marinho 654): A. abaxial side of a leaf showing vein pattern; B. posterior petal in adaxial view; C. posterior-lateral petal in adaxial view; D. anterior-lateral petal in abaxial view; E. androecium, the first stamen on the left is opposite the anterior sepal; F. stamen showing hairy anther; G. gynoecium showing the anterior style at center. Amorimia candidae R.F.Almeida (based on R.F. Almeida 594): H. abaxial side of a leaf showing vein pattern; I. posterior petal in adaxial view; J. posterior-lateral petal in adaxial view; K. anterior-lateral petal in abaxial view; L. androecium, the first stamen on the right opposite the anterior sepal; M. stamen showing hairy anther; N. gynoecium showing anterior style at center (drawings by Klei Sousa).

FIGURE 11. Illustration plate comparing flowers and fruits from species of the Amorimia rigida complex: Amorimia rigida, A. flower in frontal view, G. samara in dorsal view; Amorimia candidae, B. flower in frontal view, H. samara in dorsal view; Amorimia coriacea, C. flower in frontal view, I. samara in dorsal view; Amorimia pellegrinii, D. flower in frontal view, J. samara in dorsal view; Amorimia andersonii, E. flower in frontal view, K. mature samara unknown; Amorimia velutina, F. flower in frontal view, L. samara in dorsal view (photographs A, B, D, G, H, J—R.F. Almeida, C—M.O.O. Pellegrini, E—F. Michelangeli, I—C.N. Fraga).

FIGURE 12. Distribution map of species from the Amorimia rigida complex in eastern Brazil: white circle—A. andersonii, black circle— A. candidae, white square—A. coriacea, gray triangle—A. pellegrinii, black triangle—A. rigida, dark star—A. velutina. White area— Caatinga domain, light gray area—Atlantic Forest domain, dark gray area—Cerrado domain, dark area—Amazon Forest domain.