Thinouia restingae Ferrucci & Somner

Medeiros, Herison, Acevedo-Rodríguez, Pedro, de Carvalho Lopes, Jenifer & Forzza, Rafaela Campostrini, 2025, Taxonomic revision and phylogenetic relationships of Thinouia (Sapindaceae), a neotropical genus, PhytoKeys 252, pp. 207-273 : 207-273

7. Thinouia restingae Ferrucci & Somner , Brittonia 60 (4): 371. 2008

Figs 15 , 19 A

Type.

Brazil. Rio de Janeiro • Município Saquarema, Reserva Ecológica Estadual de Jacarepiá, próximo à lixeira , 11 May 1994, D. Araújo 10025 (holotype: RB! [724823], isotype: CTES [ CTES 0013570 ] [image!]) .

Description.

Tendrilled liana; stem cylindrical-striate or 4–5 lobed, glabrous or puberulous, lenticels rounded and ferruginous; cross-section simple when young or with neo formations when mature. Leaves trifoliolate; stipules minute, ca. 0.5 m long, puberulous, triangular; petiole 1.5–4 cm long, canaliculate, glabrous, rarely puberulous; leaflets glabrous on both sides; the leaflet secondary venation brochidodromous; secondary veins 8–10 pairs, alternate, spacing irregular; intersecondaries present; tertiary veins irregular reticulate; margins entire, sometimes undulate and rarely with 1 tooth on the base; terminal petiolule 0.1–0.5 cm long, lateral petiolules 0.1–0.2 cm long; terminal leaflet 5–8 × 2.7–3.3 cm, oblong, symmetrical or asymmetrical, apex obtuse, rounded or emarginate, mucronate, base acute to decurrent; lateral leaflet 4.7 × 2.4 cm, oblong or oblong-ovate, asymmetrical, apex obtuse, rounded or emarginate, mucronate, base decurrent or rounded. Thyrses axillary or terminal, umbelliform, 0.8–2.8 cm long, peduncle 1–4.2 cm long, secondary peduncle subsessile 0.1–0.7 cm long, cincinni numerous, peduncle of cincinnus 0.2–0.8 cm long, tomentose to glabrescent. Flower 3–5 mm long, pedicel 1.4–4 mm long, glabrous; sepals ca. 1.3 mm long, deltoid, glabrous or sometimes glabrescent, ciliate; petals ca. 2 mm long, spatulate, erose at apex, clawed, adaxially glandular and with sparse simple trichomes; petal appendages 1–1.5 mm long, shorter than the petals, bifid, sometimes distally branched, villous; nectary disc annular, glabrous. Staminate flowers with stamens 8, ca. 4.8 mm long, filaments villous on lower half, anthers glabrous; pistillode ca. 0.3 mm long, villous. Pistillate flower with staminodes 8, ca. 2 mm long; pistil ca. 3 mm long, ovary adpressed-pubescent along dorsal edges, stigma and style puberulous. Fruits chartaceous, 3.6–4.2 (5.4) × 2.6–3 cm; accrescent pedicel 3–4 mm long; stipe 3–6 mm long; seed locule lenticular; epicarp glabrous; cavity of seed locule densely villous with arachnoid, biseriate, simple or branched trichomes. Seed 6.8–7.3 × 5.2–5.6 mm, obovoid to ellipsoid, glabrous.

Distribution, habitat and phenology.

Thinouia restingae is endemic to tropical and subtropical moist broadleaf forests in SE of Brazil, in restinga vegetation and ombrophilous and semi-deciduous forests in the states of Bahia, Espírito Santo, and Rio de Janeiro (Fig. 19 A ). Flowering from October to December, and fruiting from January to August.

Notes.

Thinouia restingae and T. ventricosa have similar fruit morphology and are the only species with densely arachnoid trichomes on the locule cavity. Thinouia restingae however, is distinguished from T. ventricosa by the entire or rarely basally 1 - toothed margins (vs. dentate-serrate with 2–3 (4) teeth), 8–10 pairs of secondary veins (vs. 3–5 pairs), secondary veins framework brochidodromous (vs. semicraspedodromous), and the absent of domatia (vs. domatia on abaxial side of secondary vein axil).

Conservation status.

Thinouia restingae is represented by records distributed by the Atlantic Coast within an EOO of 95,642.60 km 2 and AOO of 58.00 km 2 in antropically modified restinga vegetation in the states of Rio de Janeiro and Espírito Santo, and less frequent in the semi-deciduous and ombrophilous forests in the states of Bahia, Espírito Santo and Rio de Janeiro. Thus, it should be regarded as Vulnerable [ VU, B 2 ab (ii, iii, iv)], due to its range of distribution being less than 100 km 2 and the number of locations being ≤ 10. Additionally, these species have a continually declining habitat quality, principally in the restinga vegetation where it faces intense pressure from human occupation.

Selecte specimens examined.

Brazil. Bahia • Mun. Jussarí, Rod. Jussarí / Palmira , 11 Feb 2003, Paixão et al. 211 ( CEPEC) . Espírito Santo • Mun. Aracruz, Retiro Serra Peladinha , 14 Dec 2007, Mansano et al. 480 ( RB) • Mun. Nova Venécia, Área de Proteção Ambiental Pedra do Elefante , 18 Feb 2008, Forzza et al. 5089 ( CEPEC, CTES, MBML, RB, UPCB) • Mun. Piúma, Estrada entre Marataízes e Piúma , 29 Nov 2006, Souza et al. 32487 ( RB) • Mun. Sooretama, Reserva Biológica de Sooretama , 12 Feb 2021, Medeiros and Toledo 4475 ( RB) . Rio de Janeiro • Mun. Armação de Búzios, Praia Gorda , 16 Dec 1998, Fernandes et al. 195 ( RB) • Mun. Cabo Frio, Parque Ecológico Municipal do Mico Leão Dourado , 29 May 2003, Fernandes et al. 855 ( RB, RBR) • Mun. Campos dos Goytacazes, Morro do Itaoca , 361 m, 15 Feb 2021, Medeiros and Toledo 4453 ( RB) • Mun. Maricá, Reserva Ecológica de Jacarepiá , 27 Feb 2021, Medeiros and Toledo 4491 ( RB) • Mun. Rio das Flores, Estrada para Rio das Flores , 2 Aug 2006, Marquete et al. 3775 ( RB, UFAPZ) • Mun. Rio das Ostras, Praia Virgem , 5 May 2016, Somner et al. 1826 ( RB, RBR) • Mun. Saquarema, Reserva Ecológica Estadual de Jacarepiá , 28 Sep 1990, Somner et al. 616 ( RB) .

Figures

Figure 15. Thinouia restingae Ferrucci & Somner A fertile branch B leaf C detail of the secondary veins and leaflet margin D lobed stem E cross-section of stem with neo formations F fruiting branch G mature schizocarp [Medeiros 4453 (A – G); photos: A by C. Toledo B – G by H. Medeiros].

Figure 19. Distribution maps of Thinouia species A Thinouia paraguayensis and T. restingae B T. scandens and T. silveirae C T. tomocarpa and T. trifoliolata D T. ternata and T. ventricosa.