Utricularia gibba Linnaeus (1753: 18)

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 : 13

8. Utricularia gibba Linnaeus (1753: 18) ( Fig. 4 : A)

Aquatic submersed herbs, inflorescence up to 15 cm above water surface. Stolons and vegetative parts glabrous. Leaves alternate, divided into capillary segments, with 1–2 primary segments. Traps lateral, with a pair of dorsal appendages, setaceous, branched and eventually with lateral and ventral simple setae. Inflorescence erect, up to 6-flowered, flowers ca. 2 cm distant from each other. Peduncle greenish; lateral spongy floats absent. Sterile bracts 0–2, ca. 1 mm long, basifixed, oblong, apex truncate. Bract up to 1.5 × 1.5 mm, basifixed, elliptic, apex rounded, margin entire. Bracteoles absent. Pedicels ca. 1 cm long, longer than the calyx lobes. Calyx lobes equal, oblong, apex rounded, margin entire, without prominent nerves; upper lobe 3 × 1.5 mm and lower lobe 2.5 × 1.5 mm. Corolla yellow, with a few darker yellow marks on the lower lip; upper lip 5 × 6 mm, ovate to circular, entire to obscurely trilobed; lower lip 5 × 5 mm, circular, entire to obscurely trilobed; spur 4–7 × 1 mm, conical, apex rounded, as long as the lower corolla lip or nearly so, and not forming an angle of 90º with the latter in lateral view. Style and filaments short. Capsule globose to ovate, dehiscing by 2 lateral slits. Seeds lenticular, winged, wings irregular, testa cells tiny and isodiametric (sometimes with conical processes).

Distribution:—We present the first record of Utricularia gibba for Roraima. This species is nearly cosmopolitan ( Taylor 1989) and is recorded in all Brazilian regions ( Miranda et al. 2016). It is found in shallow, still or slow flowing waters, or mud, pools, lakes and river backwaters, bogs, swamps and marshes, often growing among other aquatic species ( Taylor 1989), as in the areas where it occurs in VNP.

Taxonomic notes:— Taylor (1989) highlights the occurrence of cleistogamous flowers at submersed inflorescences in some specimens, but we did not observe this type of flower in the specimens collected in our study area. This species is distinguished from other species by its corolla shape (lower lip of corolla bilobed or entire), by its capsule dehiscing by two lateral slits and the seeds with irregular wings.

Specimens:— BRAZIL. Roraima, Caracaraí, Viruá National Park: “Estrada Perdida”, 25 January 2011, S.M. Costa 895, 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).