Solanum arenarium Sendtn.

  • Authority

    Knapp, Sandra D. 2002. section (Solanaceae). Fl. Neotrop. Monogr. 84: 1-404. (Published by NYBG Press)

  • Family

    Solanaceae

  • Scientific Name

    Solanum arenarium Sendtn.

  • Type

    Type. Brazil.  In Brasilia australi, Sellow s.n. (lectotype, BR, here designated).

  • Synonyms

    Solanum chloranthum Spreng., Solanum sprengelii Dunal

  • Description

    Species Description - Shrubs 0.5-2 m tall; young stems and leaves densely pubescent with beige-tan dendritic trichomes 0.25-0.5 mm long, the older stems not glabrate, the young leaves drying dark; bark of older stems reddish-brown. Sympodial units unifoliate, occasionally difoliate, geminate. Leaves elliptic, widest at the middle, with 7-9 pairs of main lateral veins, glabrous and shining adaxially, with a few scattered trichomes along the midrib, densely pubescent abaxially with congested dendritic trichomes, the lamina not visible through the interlocking trichomes, 7-16 x 3-8.5 cm, the apex acute to rounded, the base attenuate; petioles 0.6-1 cm long. Inflorescences leaf-opposed, simple, 0.2-1 cm long, 2-6-flowered, densely pubescent with dendritic trichomes like those of the young stems and leaves; pedicel scars closely spaced, not overlapping. Buds globose, the corolla strongly exserted from the calyx tube. Pedicels at anthesis slender, 0.7-1 cm long, deflexed, densely pubescent with dendritic trichomes ca. 0.25 mm long. Flowers with the calyx tube conical, 1-1.5 mm long, the lobes debate with an apical knob-like projection, 1-1.5 mm long, the lobes pubescent with dendritic trichomes, the midribs densely pubescent, the margins glabrous or sparsely pubescent; corolla greenish-white, 6-9 mm diam., lobed ca. 3/4 of the way to the base, the lobes planar at anthesis, sparsely pubescent on the abaxial surface; anthers 2-2.5 x 1-1.5 mm, poricidal at the tips, the pores teardrop shaped; free portion of the filaments ca. 0.25 mm long, the filament tube ca. 0.25 mm long; ovary glabrous; style 5-7 mm long, glabrous; stigma a minute papillose area at the tip of the style. Fruit a globose, green berry, 1-1.5 cm diam.; fruiting pedicels deflexed, woody, 1.3-1.5 cm long, ca. 1 mm diam. at the base. Seeds pale tan, ovoid-reniform, 4-4.5 x 2.5-3 mm, the surfaces minutely pitted. Chromosome number unknown.

  • Discussion

    Solanum arenarium is probably most closely related to S. gnaphalocarpon, also of SE Brazil. It differs from that species in its strongly discolorous larger leaves, glabrous fruit, and smaller flowers. The trichomes of the lower leaf surface in S. arenarium are so closely packed as to obscure the lamina. Label data indicate that the flowers of S. arenarium are pale green, while those of S. gnaphalocarpon, S. smithii, and S. tunariense are white.

    The epithet Solanum chloranthum Sprengel is the oldest available for this species, and Bitter (1920b) considered it as such. However the material cited by Bitter as type material was cultivated in Berlin after the publication date of the epithet. Thus the identity of Sprengel’s species is in doubt and the name should be considered a nomen dubium.

  • Distribution

    In forest and second growth in southern Brazil from Rio de Janeiro to Rio Grande do Sul, elevation unknown.

    Brazil South America| Rio de Janeiro Brazil South America| Rio Grande do Sul Brazil South America|