Bonamia austinii A.Moreira & Sim.

Moreira, André Luiz Da Costa, Simão-Bianchini, Rosangela & Cavalcanti, Taciana Barbosa, 2018, Two new species of Bonamia (Convolvulaceae) endemic to the Brazilian Cerrado, Phytotaxa 361 (1), pp. 106-114 : 107-112

publication ID	https://doi.org/ 10.11646/phytotaxa.361.1.9
DOI	https://doi.org/10.5281/zenodo.13704499
persistent identifier	https://treatment.plazi.org/id/135987E4-EA47-FFAD-358C-FE7002F45741
treatment provided by	Felipe
scientific name	Bonamia austinii A.Moreira & Sim.
status

Treatment

Bonamia austinii A.Moreira & Sim. View in CoL -Bianch., sp. nov.

Type: Brazil. Distrito Federal: Gama, margem da DF-290, saída para Ponte Alta , 16º01’’S 48º05’W 984 m, 10 June 2001, M.A. Silva et al. 5048. (holotype: IBGE!; isotype: SP!, MO photo!). Figs 1 View FIGURE 1 , 2 View FIGURE 2 .

Bonamia austinii is characterized by the erect to decumbent habit, greenish to ferruginous, sericeous leaves, fewflowered cymes and tomentose sepals. The species is morphologically similar to Bonamia sericea (Griseb.) Hallier f., (1893: 528) but differs by having internodes 1 cm long., the leaves with 3–4 pairs of secondary veins, brown seeds and the style divided nearly in the middle into 2 unequal branches, whereas in B. sericea the internodes are short, 5 mm long, the leaves with 4–6 pairs of secondary veins, styles unequal, bifid above middle and black seeds, glabrous.

Subshrub ca. 60 cm high, stems erect or decumbent, greenish to ferruginous, tomentose, trichomes simple; internodes 1 cm long. Leaves sessile to subsessile, petiole up to 0.3 mm long, lamina 1–4.5 × 0.5–2.5 cm, elliptic to narrowly elliptic, base cuneate to rounded, apex acute to rounded, shortly mucronate, margin entire, eucamptodromous, secondary veins 3–4 pairs, shortly sericeous on both surfaces. Inflorescence composed of axillary cymes with 1–3 flowers; peduncles 0–3 mm long, tomentose; bracteoles ca. 2 mm long, acicular to narrowly oblong, apex acuminate, tomentose, persistent; pedicels 0.2–0.4 mm long, tomentose; outer sepals ca. 0.6 × 0.3–0.4 mm, lanceolate, concave, apex acute, tomentose with simple trichomes; inner sepals ca. 0.5 mm long; corolla ca. 2 cm long, infundibuliform, white, mid-petaline bands sericeous with simple trichomes; stamens 5, unequal, white, 3 short, ca. 4 mm long, 2 long, ca. 5.5 mm long, anthers ca. 2 mm long, cream, oblong; pollen 3-colpate, apertural membrane ornamented with small spiny ubisch bodies ( Fig. 2E, F View FIGURE 2 ); ovary comose, style pilose, divided near to the middle into 2 branches of different lengths ( Fig. 2C View FIGURE 2 ), stigmas globose. Capsule 10 × 0.7 mm, ovoid, apiculate, sericeous, trichomes simple; seeds 4 mm long, ellipsoid, glabrous, brown ( Fig. 2 D View FIGURE 2 ).

Additional specimens examined (paratypes): — BRAZIL. Distrito Federal: Brasília, Estação Ecológica de Águas Emendadas, 15°33’17’’S 47°33’36”W, 06 April 2012, Zanatta & Silva 1285 ( UB). Goiás: Luziânia, planta de cerrado seco, sujeito a fogo, 02 February 1947, Heringer 14477 ( IBGE, UB).

Etymology: Named in honor of Dr. Daniel Frank Austin for his valuable contributions to the taxonomy of Convolvulaceae , and especially for his friendship and willingness to share his knowledge.

Distribution and ecology: This species is known from the Distrito Federal and Goiás state in Brazil in areas of altered cerrado subjected to fire. It was collected with flowers in February and May with fruits recorded in May. Fig. 5 View FIGURE 5 .

Conservation Status: Bonamia austinii has an extent of occurrence (EOO) of 1,101.973 km ² and an area of occupancy (AOO) of 12 km ² (GeoCAT 2018). Both values suggest that this taxon is under immediate threat because of its restricted range. This indicates that B. austinii fulfils conservation criteria B1ab (i,ii,iii) + 2ab (i,ii,iii) and its conservation status falls within the (EN) endangered category (IUCN 2012). It is important to note that the records are cited for fully conserved areas, one of the records is in the area Estação Ecológica de Águas Emendadas which is an environmental conservation area.

Notes: Bonamia austinii was treated as an unidentified species of Evolvulus L. in some herbaria, and sometimes identified as Jacquemontia fusca (Meisn.) Hallier f. (1893: 543) in others. However, Bonamia austinii can be easily distinguished from J. fusca by the presence of a pedunculate inflorescence with one to three flowers, sericeous midpetaline bands, apiculate fruits and the style divided in two branches each with a globose stigma ( Figs. 1 View FIGURE 1 , 2 View FIGURE 2 ). In contrast, Jacquemontia fusca has the sessile flowers in a spiciform inflorescence, the corolla with sparsely pilose midpetaline bands, and an entire style with the two linguiform stigmas.