Hiraea transiens Nied.

Anderson, C., 2016, Circumscription and nomenclature of Hiraea barclayana, H. reclinata, and H. ternifolia (Malpighiaceae), and of seven species misassigned to them, Blumea 61 (2), pp. 125-146 : 140-143

8. Hiraea transiens Nied. — Fig. 8 ; Map 8

Hiraea transiens Nied. (1906) 8. — Type: Triana s.n. (lecto, designated by W.R. Anderson 2007a: G; isolecto BM, COL, K, NY), Colombia, Chocó, Istmo de San Pablo [= Istmina], 100 m, 1853 ( Dugand 1944).

Woody vine to 1 m or scandent shrub to 2 m; stems sericeous when young, soon glabrous. Leaves opposite. Laminas of the larger leaves 7.5–18 by 5–8 cm, elliptical to broadly obovate, apex mucronate to acuminate-mucronate, base acute to briefly truncate, adaxially sericeous when very young but soon glabrous, abaxially appearing glabrous to the naked eye but sparsely and finely sericeous, eventually patchily glabrescent, oldest laminas glabrous but often hairs retained on and along the costa and secondary veins, the hairs 0.1–0.3(–0.5) mm long, sessile, straight; marginal glands absent or sometimes with scattered glands 0.2 mm or less diam near apex; costa and secondary veins not or slightly impressed adaxially, prominent abaxially. Petioles 8–13.5 by 1.5–1.8 mm, densely sericeous, with a pair of glands at apex or 1–1.5 mm below apex, each gland 0.6–1.2 mm long. Stipules 2–3.5 mm long, borne at middle to distal 1/4 of petiole. Inflorescences 1–2 axillary biternate cymes of 4-flowered umbels; umbel without a central gland; inflorescence axis 2–8 mm long, bracts 1–2 by 1–1.5 mm; central peduncle 3–7.5 mm long; lateral axes to 3 mm long, subtended by bracts 0.5 by 1.5 mm, each lateral axis terminat- ing in three sessile peduncles 2.5–7.5 mm long, bracts 0.5 by 1.5 mm; bracts and bracteoles subtending pedicels 0.5 by 1.5 mm; pedicels 9.5–14 by 0.3 mm; axes, abaxial surface of bracts and bracteoles, and pedicels densely sericeous; sometimes an additional lateral peduncle 2–5.5 mm long inserted below one or both lateral axes. Sepals 1.5–2 mm long and wide, triangular, adaxially glabrous, abaxially sericeous; anterior sepal eglandular, the lateral four biglandular, glands 1.3–1.5 mm long, or all eglandular. Petals yellow, glabrous; lateral petals with the claw 2–2.5 mm long; limb of anterior-lateral petals 5–6.5 mm long and wide, orbicular, margin subentire to irregularly minutely denticulate, limb of posterior-lateral petals 4.5–5.5 mm long and wide, orbicular, margin subentire to irregularly minutely denticulate especially toward apex, teeth to 0.01 mm long; posterior petal with the claw c. 3 mm long and thicker than that of lateral petals, limb 4 –5 mm long and wide, orbicular, margin glandular-dentate-fimbriate, fimbriae to 0.5 mm long. Stamens glabrous, filaments basally connate. Stamen opposite anterior sepal: filament (2.5–) 3.5 mm long, anther (1.1–) 1.5 mm long; stamens opposite anterior-lateral petals: filaments (2.1–) 2.8–3 mm long, anthers (0.8–) 1.1–1.3 mm long; stamens opposite anterior-lateral sepals: filaments (2.5–) 3.3–3.5 mm long, anthers 1–1.3 mm long; stamens opposite posterior-lateral petals: filaments (1.5–) 2.5–2.6 mm long, anthers (0.8–) 1.2 mm long; stamens opposite posterior-lateral sepals: filaments (2.5–) 3.3–3.5 mm long, anthers 0.8–1 mm long; stamen opposite posterior petal: filament 1.5–2.3 mm long, anther 0.5–0.6 mm long. Styles slightly incurved, glabrous, (2.5–)3.5–4 by c. 0.4 mm; apex of anterior style extended into a spur 0.1–0.2 mm long; apex of posterior styles extended into a spur 0.05–0.1 mm long. Ovary 0.8–1 mm long, densely villous. Mature samara not seen; immature samara butterfly-shaped, dorsal wing present.

Distribution — Northern Colombia (Antioquia, Chocó, Norte de Santander) and northern Venezuela (Distrito Federal, Mi- randa).

Habitat & Phenology — In forest, one collection ( Acevedo et al. 6863) from mangrove swamp; sea level to 200 m; collected in flower in February to April, June, September, November; in young fruit in February.

Note — Hiraea transiens is partly sympatric with H. reclinata and is often misidentified as that species (or ‘ H. obovata ’). The abaxial surface of the lamina looks glabrous to the naked eye but is covered with tiny appressed hairs, mostly 0.1–0.2 mm long. The hairs are eventually abraded. The oldest leaves are mostly glabrous, although often some hairs are retained along the costa and secondary veins, especially toward the base. Hiraea transiens also differs from H. reclinata in its biternate inflorescences, which sometimes bear one or two additional pedunculate umbels below the lateral axes ( Fig. 8d ).

Figures

Map 8 Distribution of Hiraea sanctae­marthae C.V.Morton (▲) and Hiraea transiens Nied. (◆).

Fig. 8 Hiraea transiens Nied. a. Large leaf, abaxial view; b. petiole and lamina base, adaxial view, showing a pair of glands and a pair of stipules; c. detail of abaxial leaf surface; d. inflorescence in bud; e. flower, posterior petal uppermost; f. androecium, stamen fifth from right opposite posterior petal; g. gynoecium, anterior style in centre (all from: Acevedo­R. et al. 6863, MICH). — Scale bar: a = 4 cm; b, d = 8 mm; c = 4 mm; e = 5.7 mm; f, g = 2.7 mm. — Drawn by Karin Douthit.