Sida oblonga, 2016

Bovini, Massimo G., 2016, Two new species of Sida (Malvaceae: Malvoideae) for Brazil, Phytotaxa 282 (4), pp. 291-295 : 291-293

SIDA OBLONGA Bovini , sp. nov. ( Fig. 1 )

Similar to Sida regnellii , S. oblonga is distinguished by oblong leaves, calyx with relatively long (ca. 1 mm), simple trichomes, and 9–10 mericarps.

Type:— BRAZIL. Minas Gerais: Grão-Mogol, rodovia para Cristália , 22 April 1978, G. Hatschbach et al. 41383 (holotype MBM!) .

Shrubs 1.5–2.5 m tall, erect.Adults branches terete, velutinous, trichomes simple, long (ca. 2 mm), and short fasciculate, scattered. Stipules ca. 3 mm long, linear, pilose, with trichomes simple and long (ca. 2 mm), caducous. Leaves with petioles 1–1.5 cm long, indumentum and trichomes like in the branches; lamina 2–2.5 × 1–1.2 cm, green concolorous, membranaceous, oblong, base truncate to subcordate, apex obtuse, margin serrate; adaxial surface sericeous, trichomes simple, abaxial surface tomentose, trichomes fasciculate. Synflorescence frondose-bracteate, raceme congested, 5–6 cm long; anthopodium ca. 1 cm long, indumentum and trichomes similar to that of the branches. Flowers with pedicel ca. 5 mm long, indumentum and trichomes similar to that of the branches; calyx ca. 6 mm long, ca. half-divided, sepal apex acute, tomentose, trichomes simple, long (ca. 1 mm), and fasciculate; corolla ca. 1.3 cm in diameter, slightly pink; staminal column with few scattered trichomes simple, hyaline, free portion of filaments ca. 2 mm long; ovary 9–10- celled. Schizocarp ca. 5 mm in diameter, puberulous, 9–10 mericarps, ca. 2 × 1 mm, trichomes simple and hyaline, shortly spinose, ca. 1 mm long.

Habitat, distribution, and phenology: — S. oblonga was found in the Espinhaço Mountains, at approximately 900 m. This site is considered a center of diversity for several genera, due to its high degree of endemism determined by its hilly topography. The vegetation is characterized as rocky grassland (campo rupestre), but this species was collected in a secondary growth area. Individuals of this species were found bearing flowers and fruits in April.

Conservation status: — S. oblonga was represented by a single collection. It was found outside the protected area, in an area with livestock and commercial plantations of bean, coffee and maize, which may result in population decline. According to the IUCN (2014), the species can be treated as CR B1a, with an estimated area of occurrence smaller than 100 km ².

Etymology:—The epithet “ oblonga ” refers to its oblong leaves, unique in the section Cordifoliae of the genus Sida .

Taxonomic notes:—This new species is close to S. regnellii R.E. Fries (1908: 33) , a species that occurs in Uruguay and southern Brazil. This species can be distinguished by the following characters:

1. Lamina oval-lanceolate; calyx tomentose, trichomes short fasciculate; 11–13 mericarps............................................. Sida regnellii

- Lamina oblong; calyx tomentose, trichomes simple long (ca. 1 mm), and short fasciculate; 9–10 mericarps.............. Sida oblonga

Figures

FIGURE 1. Sida oblonga. A. Flowering branch. B. Detail of branch. C. Leaf. D. Flower bud with stipules. E. Calyx. F. Mericarp. Scale bars A, B= 2 mm; C= 1 cm; D, E= 5 mm; F= 1 mm. Drawn from the holotype.