Inga ciatiformis J.M. Fernandes & F.C.P. Garcia, 2021

Fernandes, José Martins & Garcia, Flávia Cristina Pinto, 2021, Inga ciatiformis (Leguminosae): A new species from the Atlantic Forest, Brazil, Phytotaxa 505 (2), pp. 213-220 : 214-217

Inga ciatiformis J.M. Fernandes & F.C.P. Garcia , sp. nov. ( Figs. 1–2 ).

Inga ciatiformis is similar to Inga cabelo Pennington (1997: 524) by the presence of cylindrical rachises, elliptic to ovate leaflets, spiciform inflorescences, numerous stamens, and flat fruits with non-expanded margins, but differs by having appressed-sericeous young branches, cyathiform extrafloral nectaries, 1–3 leaflet pairs, and 9–13 mm long, linear, persistent bracts, while I. cabelo has hirsute or hispid young stems, capitate extrafloral nectaries, 2–5 leaflet pairs, and 2 mm long, triangular, caducous bracts.

Type:— BRAZIL. Minas Gerais: Santa Rita do Itueto , Parque Estadual dos Sete Salões, S19º 17’ 24,4” W041º 24’ 06,3”, 11 January 2010, fl., Fernandes J.M. 1178 (Holotype VIC!, Isotypes RB!, BHCB!) .

Trees, 7–8 m tall. Young branches appressed-sericeous, slightly whitish, densely lenticellate. Stipules 1–1.4 mm long, linear or lanceolate, persistent. Leaves pinnate, pulvinus 3–5 mm long; petiole 2.8–3.5 cm long, cylindrical; rachis 3.5– 7.5 cm long, cylindrical, rarely winged in the superior portion of the pair of apical leaflets; terminal appendix 7–12 mm long, linear, caducous; foliar nectary present between all leaflet pairs, stipitate, stipe 0.5 mm long, head cyathiform, 1–1.6 mm diam.; leaflets in 1–3 pairs, 6–17 × 2–7.5 cm, elliptic, rarely ovate, base acute, apex acuminate, adaxial and abaxial surfaces sparsely appressed-sericeous, with glandular trichomes. Inflorescences with spiciform units, isolated or in pairs, ramiflorous, axillary; peduncle 2.5–4.5 cm long; rachis 1.6–2.4 cm long, congested. Bracts 9–13 × 1–1.3 mm, linear, persistent. Flowers sessile, pentamerous; calyx closed in bud, 8.5–9 × 1.5–1.7 mm when open, narrowly infundibuliform, sparsely sericeous, lobes irregular, subulate; corolla 18–20 mm long, infundibuliform, sericeous; androecium with 31–50 stamens, 5–41 mm long, tube 16–17 mm long, included, greenish white; nectary disc absent; gynoecium 1-carpellate; ovary 2.3–2.7 mm long, glabrous, ovules 11–19; style 36–55 mm long, glabrous, stigma crateriform. Fruits nucoid legumes, 7–12 × 2–2.5 cm, narrowly oblong, base obtuse, apex rounded, flat, margins not expanded, with irregular constrictions, sparsely sericeous; seeds not seen.

Additional material examined (Paratype):— BRAZIL. Minas Gerais: Santa Rita do Itueto , Parque Estadual dos Sete Salões, 08 November 2009, fr., Fernandes J.M. 1157 (VIC!) .

Entomology: —The specific epithet refers to the cyathiform extrafloral nectaries that are notable in the material examined.

Flowering and fruiting period: —The species has been collected with flowers in January and fruits in November.

Distribution and habitat: —Two fertile individuals and several young were found in a fragment of semideciduous tropical forest in the municipality of Santa Rita do Itueto, about 717 meters above sea level, in the Estadual dos Sete Salões Park, in Minas Gerais, Brazil. The most common soil type in the park is the eutrophic Red Argisol, and dystrophic Red-Yellow Latosol in its surroundings ( FEAM 2010).

Taxonomic comments:— Inga ciatiformis is similar to Inga cabelo by the presence of cylindrical rachises, elliptic to ovate leaflets, spiciform inflorescences, numerous stamens, and flat fruits with non-expanded margins ( Table 1). It differs by having appressed-sericeous young branches, leaves with 1–3 leaflet pairs, terminal appendix 7–12 mm long, cyathiform extrafloral nectaries, bracts 9–13 mm long, linear, persistent, and a sparsely sericeous calyx, while I. cabelo , according to Pennington (1997) and Garcia (1998), has hirsute-hispid young branches, leaves with 2–5 leaflet pairs, terminal appendix 2.5 mm long, capitate extrafloral nectaries, bracts 2 mm long, triangular, caducous, and a hirsute calyx.

Inga ciatiformis also resembles Inga platyptera Bentham (1845: 602) by the size of the leaf appendices, irregular calyx lobes, spiciform inflorescences, flat fruits, and sometimes the cyathiform extrafloral nectaries and elliptic leaflets ( Pennington 1997, Garcia 1998, Fernandes 2011). However, it differs by the appressed-sericeous young branches, cylindrical rachises, which are rarely winged in the superior portion of the apical leaflet pair, extrafloral nectaries always cyathiform, and linear bracts, while I. platyptera , according to Garcia (1998) and Fernandes (2011), has hispid young branches, winged petioles and rachises, extrafloral nectaries generally cupuliform, and lanceolate to ovate bracts.

* Pennington (1997) and Garcia (1998). ** Pennington (1997), Garcia (1998), Fernandes (2011) and Chagas (2014).

Figures

FIGURE 1. Inga ciatiformis—A. Branch with leaves and inflorescences. B. Stipules. C. Cyathiform extrafloral nectary. D. Floral bract. E. Flower. F. Fruits. A, B, C, D, E based on J.M. Fernandes 1178 (VIC), F based on J.M. Fernandes 1157 (VIC). Illustrated by Reinaldo Pinto.

FIGURE 2. Inga ciatiformis—A. Branches with leaves and inflorescences. B. Inflorescence. C. Floral bracts. Photos: J.M. Fernandes.