Heliotropium angiospermum Murray (1770: 217)

Melo, José Iranildo Miranda De, Paulino, Renan Da Cruz, Oliveira, Regina Célia De & Vieira, Diego Daltro, 2018, Flora of Rio Grande do Norte, Brazil: Boraginales, Phytotaxa 357 (4), pp. 235-260 : 251-252

2.1. Heliotropium angiospermum Murray (1770: 217) .

Herbs or erect to decumbent subshrubs, sometimes forming clumps, 10–90 cm tall; stems diffuse, never fistulous, strigose to scabrous, trichomes simple and glandular. Leaves alternate to subopposite; blade 1.8–15.5 × 0.8–9.5 cm, membranaceous, elliptic, ovate to rhombic, apex acute, margin ciliate, base attenuate, adaxially scabrous, abaxially pubescent; venation eucamptodromous; petiole 0.2–2.5 cm long, hirsute to tomentose, not winged. Inflorescences 1–20 cm long, falsely terminal and axillary, lax to congested, without bracts; peduncle 0.6–10 cm long, glabrescent. Flowers 2.5–4 mm long, sessile; calyx 2–3.5 cm long, externally sericeous, internally pubescent to sericeous, lobes 1.8–3 mm long, elliptic to narrowly elliptic, apex acute; corolla 2.8–4 mm long, obcampanulate, white to purplish, villous externally and internally; tube 2–2.3 mm long; lobes 1.3–3.5 × 1.2–2 mm, orbicular, apex acuminate. Stamens subsessile, free; anthers 1–1.3 mm long, oval, apex apiculate, base slightly cordate. Ovary ca. 0.5 mm long, subglobose; stigma 0.5–0.8 mm long, capitate, sessile. Schizocarp 2–3 mm long, ca. 2 mm diam., depressed-globose, verruculose; nutlets 2, calyx persistent with the fruit detached; seeds 1–1.5 mm long, oblong-elliptic.

Notes:— Heliotropium angiospermum may be recognized by strigose to scabrous stems, with simple and glandular trichomes, alternate to subopposite leaves, obcampanulate corolla, capitate stigma, and depressed-globose, verruculose fruit. Illustrations of this species can be found in Melo & Sales (2005a), Melo & Semir (2008) and Vieira et al. (2013, 2015).

Geographic distribution:— Occurs in the Americas, from southern United States (Florida and Texas), Central America , the Antilles, to Argentina ( Frohlich 1981). In Brazil found in all states of the Northeast (except Maranhão), in the Southeast in the states of Minas Gerais and Rio de Janeiro ( Melo & Semir 2008). B2, B3, B6, C4, C5, C7, D2, D4, E2.

Habitat:— Caatinga, littoral.

Phenology:— Collected in flower and fruit in January, from April to August, and in November.

Selected material examined:— BRAZIL. Rio Grande do Norte: Açu, 05º34’36”S, 36º54’31”W, July 1994, fl. fr., M.A. Cosme & P.R. Rêgo 01 (MOSS). Almino Afonso, 06º11’00”S, 37º45’00”W, June 1997, fl. fr., O.F. Oliveira 5085 (MOSS). Carnaúba dos Dantas, April 2004, fl. fr., F.C. Ramalho 838 (EAN). Ceará Mirim, January 2005, fl. fr., M.I.B. Loiola 852 (UFRN). Equador, 06º56’42”S, 36º43’06”W, April 1981, fl. fr., G.F. C. Lima 131 (MOSS). Florânia, 06º07’32,8”S, 36º46’36,7”W, April 2004, fl. fr., J.I.M. Melo & S.R.S. Xavier 446 (MOSS). Ipanguaçu, 05º29’54”S, 36º51’18”W, November 1999, fl. fr., P. Rodrigues 16 (MOSS). Mossoró, 05º05’00”S, 37º27’30”W, August 1972, fl. fr., O.F. Oliveira 138 (MOSS). Pureza, 05º27’30”S, 35º43’30”W, August 1981, fl. fr., O.F. Oliveira et al. 1906 (MOSS). Santana dos Matos, 05º53’00”S, 36º20’00”W, May 1981, fl. fr., O.F. Oliveira et al. 1779 (MOSS). São Tomé, 05º50’00”S, 36º03’30”W, April 1980, fl. fr., O.F. Oliveira et al. 239 (MOSS).