Utricularia juncea Vahl (1804: 202)

Costa, Suzana M., Bittrich, Volker & Do Amaral, Maria Do Carmo E., 2016, Lentibulariaceae from the Viruá National Park in the northern Amazon, Roraima, Brazil, Phytotaxa 258 (1), pp. 1-25 : 15-16

12. Utricularia juncea Vahl (1804: 202) ( Fig. 4 : J–L)

Marsh herbs, up to 30 cm tall. Stolons and vegetative parts glabrous. Leaves nearly 0.3 mm wide, filiform. Traps lateral, without appendages. Inflorescence erect, up to 10-flowered, flowers up to 1.2 cm distant from each other. Peduncle greenish, lateral spongy floats absent. Sterile bracts up to 2 mm long, basifixed, lanceolate, apex acute, equally distributed. Pedicels 2 mm long, shorter than the calyx lobes. Bract up to 1 × ca. 1 mm, basifixed, ovate, apex acute, margin entire, 1 or 3 prominent nerves. Bracteoles up to 1 × ca. 0.3 mm, basifixed, filiform, apex acute, margin entire, one prominent nerve. Calyx lobes unequal, margin entire, 7 or 8 prominent nerves, green; upper lobe 4 × 2.5 mm, lanceolate, apex acute and curved; lower lobe 3 × 2 mm, lanceolate, apex acute, bifid or trifid. Corolla yellow; upper lip 3 × 3 mm, obovate; lower lip 5 × 6 mm, orbicular, apex obscurely bilobed; spur 5 × 1 mm, cylindrical, apex acute, as long as the lower lip of corolla and forming an angle of ca. 90° with the latter in lateral view. Style and filaments short. Capsule globose to elliptic, dehiscing by a longitudinal ventral slit. Seeds numerous, ovoid, surface reticulate, testa cells tiny, elliptic to circular.

Distribution:—This species occurs in North and Central America and in northern South America ( Taylor 1989) and tropical Africa ( Dörrstock et al. 1996). In Brazil U. juncea occurs in the northern and northeastern regions ( Miranda et al. 2016). It is found in humid savannas, marshes, lakes and pools, and frequent in shallow waters ( Taylor 1989). In the VNP the species grows in areas of grassy white-sand savannas with saturated soils.

Taxonomic notes:— Utricularia juncea is characterized by its height of up to 30 cm, by the visible nerves on the calyx lobes and the angle formed by the spur and lower lip of the corolla (∀= 90°).

Specimens:— BRAZIL. Roraima, Caracaraí, Viruá National Park : PPBio grid L1 - L2 / N2 - N3, 15 September 2010, S. M. Costa et al. 746 ( INPA!, UEC!) ; “ Estrada Perdida ”, 16 September 2010, S. M. Costa 760, F. N. Cabral ( INPA!, UEC!) ; “ Estrada Perdida ”, 19 January 2011, S. M. Costa et al. 826 ( INPA!, UEC!) ; PPBio grid N3 / L1 - L2 , 24 January 2011, S. M. Costa 868, K. G. Cangani ( INPA!, UEC!) ; “ Estrada Perdida ”, 25 January 2011, S. M. Costa 874, K. G. Cangani ( INPA!, UEC!) .

Figures

FIGURE 4. Utricularia gibba L. A. habit. Utricularia guyanensis A.DC.—B. inflorescence (detail). C. flower (lateral view, white line— position of stamens). Utricularia hispida Lam.—D–F. flower (front, posterior and lateral views).G. immature fruit. Utricularia hydrocarpa Vahl—H. inflorescence. I. flower (front view). Utricularia juncea Vahl—J. leaves. K. inflorescence (detail). L. flower (lateral view).