Gonolobinae

Follicles Morphology in Gonolobinae

The fruits of Orinoquia are described here for the first time. They are hirsute follicles bearing simple trichomes, with numerous filiform and soft projections that measure up to 18 mm long. According to Krings et al. (2008) the fruits of Gonolobinae vary externally, being follicles, that are winged or not, smooth, verrucose or with different types of projections. Yet, in the genus Gonolobus , the follicles have a slight curvature at the base, on the region where the peduncle inserts into the follicle ( Krings et al. 2008).

Within Gonolobinae , Anemotrochus Mangelsdorff, Meve & Liede (2016: 452) and Bruceholstia Morillo (2015: 207) , all of them from Mexico to Central America, have ornamented follicles. However, the morphology of the projections on the fruit are very different, as well as the vegetative and floral attributes ( Table 1 View TABLE 1 ). In Rojasia Malme (1905: 10) from Bolivia, Paraguay and Argentina, the follicles have conic projections, but the plants are pubescent with simple and glandular trichomes (vs. simple in Orinoquia ), leafy and calycinal colleters present (vs. absent), corona with five lobes (vs. 15).

In Brazil, Orinoquia shares ornamented follicles with other genera, but differs in the shape of their projections ( Liede-Schumann & Morillo 2019). In Atrostemma Morillo (2015: 198) the follicles have conical to conical-uncinate projections, in Austrochthamalia they are verrucose, and in Cristobalia Morillo, S.A. Cáceres & H.A. Keller (2016: 132) they have conical to unciform projections. In Ibatia Decaisne (1844: 599) , the fruits have tubercles or spines often partially suberized and in Riparoampelos Morillo (2015: 241) they have irregular blunt-tipped projections.

Specimen of Orinoquia yanomamica examined (holotype): VENEZUELA. Territorio Amazonas, Área del río Ocamo, entre los Yanomami , 1980, E. Fuentes 1020 (VEN barcode VEN211148 [digital image]!).

Identification key to the Gonolobinae of Mato Grosso, Brazil

1. Older leaves with elliptic to narrowly elliptic blade ..........................................................................................................................2

-. Older leaves with ovate or ovate-elliptic blade, if elliptic blade so only distally present in flowering branches ..............................4

2. Leaf blade subcordate or cordate at the base................................................................................................. Matelea matogrossensis

-. Leaf blade cuneate at the base............................................................................................................................................................3

3. Leaf blade narrowly elliptic; corolla with ovate lobes; gynostegium sessile, corona widely 5-lobate, apex rounded ........................ .................................................................................................................................................................................... Matelea pedalis

-. Leaf blade elliptic; corolla with lanceolate to oblong lobes; gynostegium stipitate, corona shortly 5-lobate, apex truncate.............. ............................................................................................................................................................................. Matelea stenopetala

4. Colleters absent adaxially at the base of the leaf blade; corolla vinaceous...................................................... Orinoquia brasiliensis

-. Colleters present adaxially on the base of the primary vein of the leaf blade; corolla white, purple or green ..................................5

5. Leaves opposite distichous, the blade truncate at the base...................................................................... Austrochthamalia purpurea

-. Leaves opposite decussate, the blade deeply cordate or auriculate at the base..................................................................................6

6. Corolla infundibuliform-urceolate, white..................................................................................................... Macroscepis grandiflora

-. Corolla rotate to subrotate, purple or green........................................................................................................................................7

7. Corolla purple.....................................................................................................................................................................................8

-. Corolla green ......................................................................................................................................................................................9

8. Branches sparsely pilose................................................................................................................................................... Ibatia friesii

-. Branches densely wooly ................................................................................................................................................. Ibatia lanosa

9. Corolla lobe apex with crisped margins; follicles straight at the base, sulcate, smooth or with small conical projections.............10

-. Corolla lobe apex with entire margins; follicles usually curved at the base, costate or winged ......................................................12

10. Corolla lobes with papillose adaxial surface ........................................................................................................... Fischeria badilloi

-. Corolla lobes with villous adaxial surface........................................................................................................................................11

11. Corolla lobes 3–4 mm long, narrowly ovate; gynostegium 1–1.5 mm long ......................................................... Fischeria polytrica

-. Corolla lobes 7–8 mm long, ovate to widely ovate; gynostegium 2.5–4 mm long.................................................. Fischeria stellata

12. Corolla up to 9 mm diam., lobes up to 5 mm long.......................................................................................... Gonolobus parviflorus

-. Corolla exceeding 15 mm diam., lobes ≥ 10 mm long.....................................................................................................................13

13. Corolla lobes oblong, not reticulate, apex acuminate.......................................................................................... Gonolobus rostratus

-. Corolla lobes ovate, reticulate, apex acute-emarginate .......................................................................... Chloropetalum denticulatum