Hiraea sanctae-marthae C.V.Morton

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 : 135-137

5. Hiraea sanctae-marthae C.V.Morton — Fig. 5 ; Map 8

Hiraea sanctae­marthae C.V.Morton (1933) 87. — Type: Walker 1211 (holo US; iso MO, WIS), Colombia, Magdalena, Río Frío, Quebrada Rodríguez , Santa Marta , 15 Mar. 1925.

Woody vine to 8 m or shrub to 3 m; stems densely sericeous when young, becoming glabrous. Leaves opposite. Laminas of the larger leaves 6.5–20 by 3–8.5 cm, elliptical to obovate, apex mucronate, base slightly cordate, adaxially sericeous when very young, soon glabrous, abaxially densely silvery sericeous and the epidermis hidden, hairs 0.3–1.2 mm long, sessile or subsessile, straight or wavy, with age the vesture thinning and older laminas becoming thinly sericeous and eventually glabrate; margin without glands or sometimes with a few scattered glands c. 0.2 mm diam near apex; costa and secondary veins not or slightly impressed adaxially, prominent abaxially. Petioles 3–8 by c. 2 mm, densely sericeous, with a pair of glands at apex, each gland 0.7–1.2 mm long. Stipules 1.5–3 mm long, borne at base of petiole. Inflorescences solitary axillary ternate cymes of 4-flowered umbels; umbel without a gland in the centre; inflorescence axis 0–1.5 mm long, bracts 0.8–1.7 and wide; central peduncle 1–6 mm long; lateral axis 0–0.5 mm long, subtended by bracts 1.2–2 mm long and wide; lateral peduncles 0.5–7.5 mm long; bracts and bracteoles subtending pedicels 1–2 mm and wide, triangular; pedicels 11–25 by c. 0.3 mm; axes, abaxial surface of bracts and bracteoles, and pedicels densely sericeous. Sepals 1.8–2.2 by 1–1.5 mm, triangular, adaxially glabrous, abaxially sericeous; anterior sepal eglandular, the lateral four biglandular, glands c. 1.5 mm long, prominent, or all sepals eglandular, or all sepals glandular. Petals yellow, glabrous; lateral petals with the claw 2–2.5 mm long, limb of anterior-lateral petals 5.5–6.5 mm long and wide, orbicular, margin subentire, limb of posterior-lateral petals 5–5.5 mm long and wide, orbicular, margin minutely and irregularly denticulate, especially distally, sometimes subentire; posterior petal with the claw c. 2.5 mm long and thicker than that of lateral petals, limb c. 5 mm long and wide, orbicular, margin irregularly dentate-fimbriate, teeth/fimbriae 0.2–0.3(–0.5) mm long. Stamens glabrous, filaments basally connate. Stamen opposite anterior sepal: filament 3.5–5 mm long, anther 1.1–1.3 mm long; stamens opposite anterior-lateral petals: filaments 3–4 mm long, anthers 0.8–1 mm long; stamens opposite anterior-lateral sepals: filaments 3.5–4 mm long, anthers 1–1.3 mm long; stamens opposite posterior-lateral petals: filaments 2.5– 3 mm long, anthers (0.5–) 0.8 mm long; stamens opposite posterior-lateral sepals: filaments 3–4 mm long, anthers 0.8–1 mm long; stamen opposite posterior petal: filament 2–2.5 mm long, anther 0.5–0.6 mm long. Styles incurved, glabrous, 3–3.5 by 0.4–0.5 mm; apex of anterior style extended into a spur c. 0.3 mm long; apex of posterior styles extended into a spur 0.1–0.2 mm long. Ovary 1–1.5 mm long, densely villous. Mature samara not seen; immature samara butterfly-shaped, dorsal wing present.

Distribution — Northern Colombia (Atlántico, Cesar, Magdalena).

Habitat & Phenology — In dry forest and thickets; sea level to 200 m; collected in flower in April and October, in young fruit in May.

Notes — Flowering and fruiting specimens of H. sanctae­marthae are easily distinguished from all other species here discussed by the silvery appressed vesture on the abaxial surface of the laminas, which is so dense that the epidermis is hidden. Yet, this distinctive vesture eventually thins. Old leaves become abaxially thinly sericeous to eventually glabrate; they may appear glabrous to the unaided eye and lead to confusion with H. reclinata . The retained hairs are generally aligned and parallel, unlike in H. reclinata , where the retained hairs are scattered. Also, in H. sanctae­marthae the stipules are at the base of the petiole. Three collections by Gentry and collaborators from Cesar are sterile and show the transition of the abaxial indumentum. This change is especially well shown in Gentry et al. 60742 (MO), which consists of two branches, one of which terminates in a young internode with a smaller leaf that shows the typical dense vesture; the other leaves show the gradual thinning. Such an abrupt change in abaxial vesture from very dense to glabrescent or glabrous is also observed in some other species of Hiraea , e.g., H. idroboana Cuatrec. , H. buntingii W.R.Anderson , and other Malpighiaceae , e.g., Stigmaphyllon crenatum C.E.Anderson (C. Anderson 1997) . Collections of H. sanctae­marthae with the dense abaxial vesture evident have been misidentified as H. velutina , and those in which the vesture was not obvious as H. hookeriana or H. reclinata .

The holotype and WIS isotype are numbered ‘1211’, but the MO duplicate is numbered ‘11’. All other data agree, and the specimens appear to be from the same gathering .

Figures

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

Fig. 5 Hiraea sanctae­marthae C.V.Morton a. Branch bearing inflorescences and at apex a flush of new leaves; b. large leaf, abaxial view; c. detail showing dense abaxial vesture of lamina and a pair of glands at apex of petiole; d. detail showing stipules borne at base of petioles; e. inflorescence; f. posterior petal; g. posterior-lateral petal; h. anterior-lateral petal; i. androecium, stamen second from left opposite posterior petal; j. gynoecium, anterior style in centre (from: a. Haught 3743, US; b–h. Smith 1514, GH; i–j. Walker 1211, US). — Scale bar: a–b = 4 cm; c–d = 8 mm; e = 1 cm; f–h = 4 mm; i–j = 2.7 mm. — Drawn by Karin Douthit.