Three species of Celastraceae, each represented by many collections from Costa Rica, are compared to near relatives and found to be new: Gymnosporia haberiana Hammel, disjunct from Mexico and Costa Rica; Maytenus recondita Hammel, of Costa Rica and Panama; and Crossopetalum enervium Hammel, of Costa Rica. The South American Gymnosporia magnifolia (Loesener) Lundell is here confirmed as a synonym of G. urbaniana (Loesener) Liesner, and Crossopetalum eucymosum (Loesener & Pitter) Lundell is placed in synonymy under C. parviflorum (Hemsley) Lundell. Keys are provided for all accepted neotropical species of Gymnosporia, and for all Costa Rican species of Crossopetalum and Maytenus. For nearly 20 years collections of two large, cloud forest trees in the family Celastraceae have been accumulating, primarily from the Monteverde region of Costa Rica. Much of this material has been distributed to various herbaria under tentative or approximate names. More recent exploration along the central cordillera has extended the range, within Costa Rica, of these two species and yielded many collections of a third, shrubby species in the genus Crossopetalum, also known from the Monteverde region. The two trees are known almost exclusively from mid-elevations on the Pacific slopes of the northern mountains, while the shrub extends nearly the entire length of the country and is known from numerous collections on both slopes. Although one of the trees has always been known to be a Maytenus presumably related to M. schippii Lundell, generic placement of the other has been more problematic. This species, while having alternate leaves and capsulate fruits with arillate seeds, as in Maytenus, has greener drying, entire leaves, more open and branched inflorescences with 4-merous flowers, and several-seeded, 2-4-lobed fruits. In these respects the Costa Rican (and Mexican) tree can be distinguished from other alternate-leaved Celastraceae and coincides perfectly with two South American species recently described in or transferred to the genus Gymnosporia (Lundell, 1985; Liesner, 1993). Gymnosporia haberiana Hammel, sp. nov. TYPE: Costa Rica. Guanacaste: Cordillera de Tilarin, La Cruz de Abangares, 1400 m, 15 July 1985 (fl), Haber & Bello 2034 (holotype, INB; isotypes, BM, C, CAS, COL, CR, DUKE, F, FLAS, GH, HNMN, K, MEXU, MICH, MO, NY, P, PMA, TEX, US, USJ, W, WIS). Figure 1. A G. gentryi Lundell foliorum nervis lateralibus minus prominentis et latiore divergentibus, ovario et capsula tantum lobato non anguloso, a G. urbaniana floribus majoribus, disco manifesto, ab ambobus sepalis latioribus quam longioribus. Dioecious trees (3-)5-30 m, the inner bark bright yellow; twigs terete; leaves and twigs drying pale to yellowish green, glabrous. Leaves alternate, 7-12(-14) X 3-6(-8) cm, elliptic, the apex acute to acuminate, the base acute to rounded, the margin entire and often curled under, all leaves often folded and curved along the midrib; main lateral veins mostly 4 or 5; petioles 5-10 mm; stipules small, deciduous. Inflorescences 2or 3-branched, ca. 10-20-flowered axillary cymes, the rachis minutely and sparsely farinose-puberulent, the pedicels 2-4 mm. Flowers 4-merous, ca. 4.5-7 mm wide, greenish; sepals ca. 0.4 X 1 mm, broadly rounded; petals imbricate, ca. 0.4 X 1 mm, spatulate or ligulate ca. 0.4 x 1 mm; stamens exceeding the style in staminate (pollen-bearing) plants, shorter than the style and without pollen in pistillate plants, anthers _ cordate, versatile; ovary ? globose, confluent with the conically raised disk, 2-celled with 2 ovules per cell. Fruits ca. 1 X 1-1.5 cm, globose or often wider than long and 2-4-lobed, (1)2-4seeded; seeds dark brown with white aril. Additional specimens examined. COSTA RICA. Alajuela: Cordillera de Guanacaste, P. N. Rinc6n de la Vieja, 10047'50N, 85018'19W, 1500 m, 6 July 1991(fl), Rivera 1423 (CR, F, INB, MICH, MO, USJ, W). Guanacaste: Cordillera de Guanacaste, P. N. Guanacaste, Volcain Cacao, ca. 10055'45N, 85028'15W, 1100-1400 m, 25 Nov. 1989 (fr), Chdvez 7 (CR, F, MO), Dec. 1990 (fr), 478 (CR, F, INB, MO), July 1989 (fl), Hammel 17661 (BM, CAS, COL, CR, F, INB, MEXU, MO, TEX, US), 9 Feb. 1995 (fr), Quir6s 48 (CR, INB, MO); P. N. Rinc6n de La Vieja, sendero al Volcain, 10045'50N, 85019'50W, 820 m, Jan. 1991 (fr), Rivera 974 (CAS, CR, F, INB, MO). PuntarNovoN 7: 147-155. 1997. This content downloaded from 157.55.39.180 on Mon, 25 Apr 2016 06:04:45 UTC All use subject to http://about.jstor.org/terms