Frangula discolor var. mesoamericana (L. A. Johnst. & M. C. Johnst.) A. Pool, ined.; Rhamnus sphaerosperma var. mesoamericana L. A. Johnst. & M. C. Johnst.

 

Small to large tree or shrubs, 0.3--10 m, young branches dense (rarely sparse) tomentose (sometimes pilose), with golden or reddish golden trichomes, sometimes pale (rarely off-white), sometimes with additional spreading trichomes. Leaves with blades (2.2) 5.5—17 x (1.4-- ) 2—7.5 cm, elliptic, or less frequently, oblanceolate, membranaceous to subcoriaceous, unicolored or less frequently bicolored with the abaxial surface drying light gray, 7--11 pairs of lateral veins, lateral veins at 45–75 degree angle to midrib, adaxial surface sparse to dense, tomentose or pilose with trichomes in tufts of 2—4 from one point or sometimes with trichomes solitary and appressed to ascending or spreading or stellate-sessile trichomes with arms tortulose, trichomes sometimes restricted to venation, abaxial surface with various densities of sessile-stellate tightly appressed trichomes, infrequently matted and totally covering surface, rarely just restricted to leaf margins, venation often tomentose with small-tufted trichomes and/or with spreading long-tufted trichomes, or sometimes trichomes solitary, the long-tufted and solitary trichomes sometimes tortulose or sometimes more or less straight and extending laterally from sides of midrib and often lateral veins, and then sometimes macroscopically conspicuously concentrated along sides of midrib and/or in angles of lateral veins, base cuneate, obtuse, truncate or rounded, sometime inequilateral, margin usually recurved, sometimes flat, when recurved teeth difficult to observe, with 2--7 teeth/cm, often only apical gland apparent or serrulate (rarely serrate), apex acuminate, less frequently obtuse then cuspidate, or acute, tip often mucronate; stipules very early caducous, 1.5—4.5 mm; petiole 5--28 mm. Inflorescence a sessile fascicle or a pedunculate and umbelliform cyme, umbelliform cluster or fascicle with (1--) 3--25 flowers, peduncle 0--17 mm, 1/5 to slightly longer than subtending petiole (similar in fruit). Flowers on pedicels 1.5--7 mm, 1/6--4/5th length of peduncle when present, 1/6 to equaling length of subtending petiole (2.5—14 mm long in fruit, 1/5^th to 2 times length of peduncle, when present, 1/6 to equaling to rarely slightly longer than subtending petiole); flower (1.7--) 2—3 (--3.25) mm, hypanthium more or less tubular, 0.9—2 x 1.25—2.5 (3) mm, hypanthium width (rarely 2/3rds) ca. equal flower length, densely tomentose, circumscissile. Sepals, petals and stamens lost early with upper portion of hypanthium. Sepals 0.7—1.3 mm long and wide, slightly shorter than hypanthium in length, erect to slightly spreading. Petals 0.75—1.2 mm long and wide, broadly apically bi-lobed, abaxially pubescent on midrib, slightly exserted; stamens with filaments 0.5—0.9 mm, anthers 0.5—0.6 mm, infrequently visible free from petals. Ovary or glabrous, style 0.6--0.75 (1.25) mm, stigma 3-lobed. Young fruits 1—5 (7) fascicled, glabrous, globose or obovoid, 3 lines not observable to more or less conspicuous; all sepals, petals and stamen filaments rapidly lost, hypanthium remnant 0.5—1 (1.5) x 2—3 (3.5) mm, not angled to weakly angled; stones 3, ca. 5--6 x 4--5 mm.

 

Rare, bosque húmedo, elfin forest, Estelí, Jinotega and Atlántico Norte; 1180—1350 m; fl abr, immature fruit abr, may, sep; Moreno 17490, Sandino 4319; Mexico (Chiapas) to Nicaragua. This variety was originally described within the species Rhamnus sphaerosperma Sw. (= Frangula sphaerosperma (Sw.) Kartesz & Gandhi,endemic to Jamaica and Cuba) which differs in retained stipules (vs. early caducous), often smaller pedicels, 1.5—3 mm in flower and 1.5—4 mm in fruit (vs. 1.5--7 mm and 2.5—14 mm), hypanthium campanulate (vs. more or less tubular), and petals and anthers well exserted (vs. rarely slightly exserted apically) and the lack of the appressed, sessile stellate trichomes (found on the abaxial leaf surfaces of F. discolor). Frangula discolor var. mesoamericana is questionably separated from the typical variety of F. discolor by the lack of trichomes on the ovary and fruit. In the published Flora de Nicaragua Frangula discolor var. mesoamericana (as Rhamnus sphaerosperma var. mesoamericana) was treated as expected. The specimens cited above were treated as a very variable and wide- spread R. sphaerosperma var. polymorpha (Reissek) M. C. Johnst. Also included within this taxon by Johnston & Johnston (1978) (as R. sphaerosperma var. pubescens (Reissek) M.C. Johnst.) were specimens pertaining to Frangula pendula A. Pool, in press, a species endemic to Costa Rica and Panama that might possibly be found in Nicaragua. It can be recognized by its flowers, 2.75—4 (4.5) mm long with a narrow-tubular hypanthium (hypanthium width/flower length ½--3/4 (4/5)) and erect sepals. It also always has glabrous ovaries and fruits, the leaves never have any appressed, sessile stellate trichomes and the inflorescences and infructescences are always pedunculate cymes which are almost always compound with the first branch strongly divaricate.