Lycianthes hypoleuca Standl., Trop. Woods 9: 12. 1927

Dean, Ellen, Poore, Jennifer, Anguiano-Constante, Marco Antonio, Nee, Michael H., Kang, Hannah, Starbuck, Thomas, Rodrigues, Annamarie & Conner, Matthew, 2020, The genus Lycianthes (Solanaceae, Capsiceae) in Mexico and Guatemala, PhytoKeys 168, pp. 1-333 : 1

23 Lycianthes hypoleuca Standl., Trop. Woods 9: 12. 1927 Fig. 52

Solanum hypoleucum (Standl.) C.V.Morton, Contr. Univ. Michigan Herb. 4: 27. 1940. Type: Based on Lycianthes hypoleuca Standl.

Type.

Belize. Orange Walk: 10 Oct 1926, H. W. Winzerling V-14 (holotype: US [00027883]; isotypes: F [0072913F, acc. # 573777]), G [G00379122], WIS [00000961MAD]).

Description.

Scandent shrub to twining woody liana, 2.5-5 m tall (or taller, described as climbing high into the tree canopy). Indument white to tan, uniseriate, multicellular, sessile to short-stalked, stellate or multangulate-stellate, eglandular, spreading trichomes 0.1-0.2 mm long, 0.1-0.25 mm in diameter, the rays 3-6 per whorl, straight, not rebranched. Young stems greenish, sparsely to densely pubescent, compressed at the nodes when dried in a plant press, becoming dark reddish brown and woody with age; upper sympodial branching points monochasial and dichasial. Leaves simple, the leaves of the upper sympodia paired or not, the pairs unequal in size, the larger ones with blades 3-11 (12.8) × (1.8) 1.5-5 cm, the smaller ones (often not developing) with blades 2.5-6.2 × 1-3.6 cm, the leaf pairs similar in shape, the blades ovate, elliptic, or obovate, chartaceous, the two sides of the blade very different in color, the adaxial side green, glabrous, the abaxial side pale, densely pubescent with overlapping trichomes, the base cuneate to attenuate, sometimes oblique, the margin entire, usually irregularly undulate, the apex acute to acuminate, the petiole 0.2-2.5 cm long, sometimes absent, the larger leaf blades with 3-6 primary veins on each side of the midvein. Flowers solitary or in groups of 2-3, axillary, oriented horizontally; peduncles absent; pedicels 12-33 mm long and erect to arching in flower, 20-35 mm long (probably longer) and erect in fruit; calyx 2.5-4.5 mm long, 2.5-4 mm in diameter, campanulate, moderately to densely pubescent, the margin truncate, undulate or lobed, the appendages lacking; fruiting calyx enlarged, bowl-shaped to rotate, 2.5-4 mm long, 6-8 mm in diameter; corolla 0.8-1.2 cm long, rotate in orientation, entire to shallowly stellate in outline, divided ca. 1/4 of the way to the base), with abundant interpetalar tissue, white, adaxially sometimes with green markings at the base of the lobes, glabrous, abaxially moderately puberulent near the major veins; stamens equal to slightly unequal, straight, the four short filaments ca. 1 mm long, the one long filament 1-2 mm long, glabrous, the anthers 3-4 mm long, ovate to oblong, the tips narrowed, free from one another, yellow (drying brownish perhaps due to glandular exudate), bumpy in texture, poricidal at the tips, the pores ovate, dehiscing distally, not opening into longitudinal slits; pistil with glabrous ovary, the style 7-9 mm long, linear, straight to curved, glabrous, the stigma capitate, slightly bilobed, decurrent down two sides. Fruit a berry, 6-12 mm long, 8-13 mm in diameter, depressed globose, orange to red when mature, glabrous, lacking sclerotic granules. Seeds 20-40 per fruit, 2.5-3 × 2-2.5 mm, flattened, oval in outline, with slightly thickened margin, yellow-orange to brown, the surface reticulum rough with indistinct serpentine pattern and deep luminae.

Chromosome number.

Unknown.

Distribution and habitat.

Mexico (Campeche, Chiapas, Quintana Roo), Guatemala ( Petén), Belize, and Honduras, in primary or disturbed tropical moist forest and tropical dry forest, on slopes and ridges, in ravines, often on limestone, 0-800 m in elevation (Fig. 53 ).

Common names and uses.

Mexico. Chiapas: tumat zak (Tzeltal) (A. Méndez G. 9067).

Phenology.

Flowering specimens have been collected from May through October; specimens with mature fruits have been collected from June through October. In Belize, corollas open in the early morning (sometimes before sunrise) and close by sunset ( Smith and Knapp 2002).

Preliminary conservation status.

Lycianthes hypoleuca is a species ranging from southern Mexico to Honduras, represented by 33 collections and occurring in four protected areas. The EOO is 78,970.5 km2, and the AOO is 124 km2. Based on the IUCN (2019) criteria, the preliminary assessment category is Least Concern (LC).

Discussion.

Lycianthes hypoleuca is a distinctive species of lowland Caribbean forest. It is easily identified based on its leaves. The whitish, tomentose, stellate pubescence of the underside of the leaf surface makes the underside much paler than the upper side. The pollination of this species was studied in Belize by Smith and Knapp (2002) and they found that a number of different bee species visit the flowers.

Representative specimens examined.

Guatemala. Petén: 2 mi S of entrance of Tikal National Park, [17.2107, -89.6247], 500 ft, 19 Jun 1973, T.B. Croat 24707 (MO). Mexico. Campeche: Mpio. Calakmul, N de Rancho Ek Sacrificio, camino a nuevo centro de población Ejidal Ley de Fomento Agropecuario, 17.9897, -89.3944, 61 m, 5 Aug 1997, E.M. Martínez S. 28113 (NY). Chiapas: al SW de Santo Domingo, [17.0458, -91.4317], 30 Jul 1982, J.M. Quintanilla 14 (MO). Quintana Roo: a 2 km al norte de Estero Franco, sobre la carretera La Unión-Ucum, [17.9512, -88.8769], 20 Aug 1983, E. Cabrera-C. 5444 (MO, NY).

Figures

Figure 52. Image of herbarium specimen of L. hypoleuca, Mendez 9067 (MO). Specimen used with permission from the Missouri Botanical Garden (http: // www. tropicos. org).

Figure 53. Map of geographic distribution of L. hypoleuca based on herbarium specimen data.