Ipomoea tarijensis O'Donell

Wood, John R. I., Munoz-Rodriguez, Pablo, Williams, Bethany R. M. & Scotland, Robert W., 2020, A foundation monograph of Ipomoea (Convolvulaceae) in the New World, PhytoKeys 143, pp. 1-823 : 1

88. Ipomoea tarijensis O'Donell , Lilloa 30: 53. 1960. ( O’Donell 1960: 53)

Type.

BOLIVIA. Tarija, 1904, K. Fiebrig 2655A (holotype BM000758194, isotypes K, P).

Description.

Trailing herb, stems up to 2 m long, thinly pubescent. Leaves petiolate, 5-11 × 5-11 cm, ovate to suborbicular, narrowly cordate with rounded, overlapping auricles, apex shortly acuminate, adaxially almost glabrous, abaxially bluish-grey with prominent, raised veins, scurfy-pubescent; petioles 3-6 cm, thinly pubescent. Inflorescence of long-pedunculate, 1-3(-5)-flowered, axillary cymes, peduncles 7-15 cm, straight; bracteoles caducous; secondary peduncles 0.5-1.6 cm; pedicels 0.5-2.5 cm, scurfy-pubescent, slightly widened below calyx, often fracturing at summit; sepals subequal, 7-9 × 4-5 mm, broadly oblong, obtuse, thinly scurfy-puberulent, margins scarious, glabrous, inner c. 1 mm longer and broader with broad scarious margins; corolla 4.5-5 cm long, shortly funnel-shaped being flared from just above basal tube, glabrous, pale pink, limb c. 5 cm in diam., distinctly lobed with rounded lobes, stamens held at corolla mouth. Capsules ovoid, 2 cm long, shortly rostrate, glabrous; seeds 6 mm long, densely lanate.

Illustration.

Figures 6G , 56 .

Distribution.

Endemic to Tarija Department in Bolivia, where it grows on open stony banks, in abandoned fields and in scrubby gullies around 2500 m, particularly on and around the Cuesta del Condor.

BOLIVIA. Tarija: Cercado, J.R.I. Wood 15954 (K, LPB); Cuesta del Condor, J.R.I. Wood 27920 (OXF, K, LPB, USZ); O’Connor, S.G. Beck et al. 22202 (LPB, SI).

Note.

O’Donell (1960) compared this species with Ipomoea jujuyensis and I. lilloana . From the latter it is easily distinguished by the glabrous buds; from the former it is less easily distinguished by the trailing habit, oblong rather than elliptic sepals, the overlapping leaf auricles, the short stamens (2.5 cm, not 4-5 cm long) and the long hairs on the seeds.

The stamens of Ipomoea tarijensis are visible at the mouth of the corolla but are unusually short, a character it shares with I. reticulata . Molecular studies suggest these two and I. saopaulista form a single clade.

Figures

Figure 6. Sepals of Ipomoea species. A I. argyreia B I. tricolor C I. argentea D I. syringiifolia E I. eriocalyx F I. procurrens G I. tarijensis H I. regnellii. Photographs of A (Mendoza 4899); C (Mendoza 4705) and F (Mendoza 4900) by Moises Mendoza; B (Wood & Soto 27960) and H (Wood & Soto 27951) by Daniel Soto; D by Hector Keller; E (Wood et al. 27809) by Beth Williams; G (Wood 27920) by John Wood.

Figure 56. Ipomoea tarijensis A habit from apex of stem B adaxial leaf surface C abaxial leaf surface D bud and sepals E corolla opened out to show stamens F fruiting inflorescence G seed. Drawn by Eliana Calzadilla from Wood 27920.