Monographs Details: Rhamnus sharpii L.A.Johnst. & M.C.Johnst.
Authority: Johnston, Marshall C. & Johnston, Laverne A. 1978. Rhamnus. Fl. Neotrop. Monogr. 20: 1-96. (Published by NYBG Press)
Synonyms:Rhamnus capraeifolia var. discolor L.A.Johnst. & M.C.Johnst., Rhamnus discolor (Donn.Sm.) Rose, Rhamnus capraeifolia subsp. discolor (Donn.Sm.) Grubov, Frangula discolor (Donn.Sm.) Grubov
Description:Description - Shrubs or trees 2.0-15.0 m tall, bark usually with prominent lenticels, entire plant moderately to densely beset with hairs and almost always on some part of the plant scattered groups of 2-6 hairs arising from a single point. Bud scales absent. Petioles (5.0-)8.0-15.0(-20.0) mm long. Stipules 1.5-3.0 mm long, subulate, dark and sometimes with a reddish cast, quickly deciduous. Leaf-blades coriaceous or firmly membranaceous with rare exception, 5.0-15.0(-17.0) cm long, (1.3-)2.0-6.0(-8.0) cm wide, usually elliptic (rarely obovate), ca 2-3 times longer than wide; base cuneate to rounded; apex acuminate (rarely acute); margin revolute, serrate, or crenate, usually remotely so, or even entire, teeth occasionally mucronate; above dark or dull green and from moderately to sparsely beset with hairs, sometimes becoming glabrous with age; beneath silvery or hoary, tomentose (hairs short and subappressed) with hairs almost always obscuring the epidermis; midrib above (and occasionally other veins) sulcate and usually pubescent, veins beneath with somewhat denser pubescence than above, prominent, midrib raised and dark-colored or yellowish, secondary veins 6-10(-13) pairs. Inflorescence an axillary umbel with (4-)7-15(-20) flowers; peduncles absent in Costa Rica and Panama collections, otherwise mostly 2.0 mm long but also up to 8.0 mm (Skutch 1720 has sessile buds, short pedunculate flowers and long pedunculate fruits); pedicels 1.0-5.0 mm long; buds spherical and subspherical in Guatemala, Costa Rica, and Panama and angular in Mexico; floral cup 1.0-1.5 mm deep, 1.5-2.25 mm broad, sepals 5, 1.0-1.5 mm long and wide; external floral parts moderately to usually densely hairy; petals 5, ca 0.7-1.0 mm long and broad, margin shallowly scalloped, notch shallow and broad; anthers 5 with short blunt apicules in Mexican and Guatemalan collections which have very short pedunculate or sessile inflorescences, small or no apicules in Guatemalan collections which have peduncles, and well-defined apicules in Costa Rican and Panamanian collections; ovary pubescent usually densely so with long hairs, style 3-lobed at apex and extending only slightly above base of sepals; peduncles in fruit lacking or 2.0-3.5(-8.0) mm long; pedicels 2-6 mm long; fruits 5.0-8.0 mm in diam, beset with sparse to moderately dense amounts of long hairs (rarely glabrous), 3-seeded.

Discussion:Rhamnus sharpii and R. sphaerosperma var mesoamericana are found in approximately the same geographic areas. Because it is difficult with some specimens to distinguish definitely between the two species, it would seem to us that R. sharpii is more closely related to the R. sphaerosperma group than to the R. capraeifolia group with which it was originally linked. Certainly it is nothing like R. capraeifolia var capraeifolia. Its designation by Rose as a distinct species, R. discolor, is much more plausible; but we have changed this name because of the prior use of it for a fossil species.
Distribution:Mexico North America| Chiapas Mexico North America| Guatemala Central America| Huehuetenango Guatemala Central America| Quiché Guatemala Central America| Alta Verapaz Guatemala Central America| Zacapa Guatemala Central America| San Marcos Guatemala Central America| Quezaltenango Guatemala Central America| Guatemala Guatemala Central America| Jalapa Guatemala Central America| Costa Rica South America| Alajuela Costa Rica Central America| Panama Central America| Chiriquí Panamá Central America|

Common Names:Palo liso, duraznillo