Hiraea tepuiensis Steyerm.

Authority

Maguire, Bassett. 1978. The botany of the Guayana Highland--part XI. Mem. New York Bot. Gard. 32: 1-391.

Family

Malpighiaceae

Scientific Name

Hiraea tepuiensis Steyerm.

Description

Species Description - Woody vine (or small tree? cf discussion); stems sericeous to eventually glabrescent. Lamina of the larger leaves 6-15 cm long, 3-6(-7) cm wide, ovate or elliptical or occasionally obovate, cuneate or rounded at the base, acuminate at the apex, loosely sericeous or subtomentose to glabrescent on both sides except persistently sericeous on the midrib especially below at base, eglandular, the veins about as prominulous above as below; petiole 6-15 mm long, sericeous, biglandular on distal half; stipules 0.5-1 mm long, borne at or above the middle of the petiole. Inflorescence an unbranched axillary umbel (1-5 per axil) of 4 flowers borne on a bibracteate peduncle 5-15 mm long, the umbel without a prominent cushion between the bracteoles or rarely with a glandular knob up to 0.7 mm in diameter, the bracts and bracteoles of the umbel 0.7-1.5 mm long, triangular, abaxially sericeous. Pedicel 8-15 mm long, reddish- or brown-sericeous. Sepals triangular, abaxially sericeous, eglandular or the 4 lateral sepals bearing 8 circular or elliptical glands 1.5-2 mm long. Petals eglandular, laciniate, the laterals yellow, with the claw 1.5-2.5 mm long, the limb 4-5 mm long, 4.5-5 mm wide, ± concave; posterior petal "salmon," with the claw 2.5-3 mm long, the limb 3 mm long, 3.5-4 mm wide, flat or crumpled. Filaments 2.5-3.5 mm long opposite the sepals, 1.5-2.5 mm long opposite the petals, basally connate, straight or slightly sinuous; anthers 0.7-1 mm long, with an apically glandular connective. Ovary ca 1 mm high, hirsute; styles 2.8-3.5 mm long, glabrous or with scattered hairs, the anterior shorter and nearly straight, the posterior 2 arcuate, with a short rounded dorsal hook at the apex. Samara with the lateral wings 6-10 mm wide, 13-18 mm high, reddish (immature), subcircular or elliptical or trapezoidal, sinuate at the margin, loosely sericeous; dorsal wing 0.5-1.5 mm wide, 2-2.5 mm high, triangular; nut ca 2 mm in diameter, loosely sericeous, the ventral areole ca 0.5 mm in diameter.

Discussion

Type. Pinkus 90, SW slopes of Mt. Roraima, vicinity of Arabupu, Mt. Roraima District, Bolivar, Venezuela, elev 1380 m, 28 Dec 1939 (holotype F!, isotypes GH! NY!). This is one of the few truly upland species of Hiraea in Guayana, most of the collections having come from above 1000 m. In most cases the plant is described as a liana, but four collections are said to have come from trees (small tree: Cowan & Wurdack 31408, Lasser 1769; tree 8 m: Wurdack 34029; tree 12 m: Steyermark 60790). It seems unlikely that all of these experienced collectors were mistaken, but it would also be very suprising if a high-climbing species of Hiraea could also occur as a tree. Resolution of this problem must await further observations in the field.

Distribution

Distribution. Mountains of southern Venezuela, usually above 900 m. VENEZUELA. Bolívar: margen de la selva, Kavanayen, elev 1300 m, Lasser 1769 (F, NY, VEN); type, qv; Ptari-tepui, SE-facing slopes, elev 1585-1600 m, Steyermark 60039 (VEN); lower portion of Quebrada O-paru-ma, tributary of Rio Pacairao, below Santa Teresita de Kavanayen, elev 915-1065 m, Steyermark 60568 (NY); Ptari-tepui, dense forest at base of cerro along Río Karuai, elev 1220 m, Steyermark 60636 (NY); along Rio Karuai, at

Venezuela South America|