New Species of Cyclanthera (Cucurbitaceae) from Mexico and Central America C. Eugene JonesDepartment of Biological Science, California State California 92634, U.S.A. Denis M.Missouri Botanical Garden, P.O. Box 299,ABSTRACT. Five new species of Cyclanthera arehere described: C. cogniauxii from the Central Cor-dillera of Costa Rica; C. dieterleana from Durango,Mexico; C. dioscoreoides with a disjunct distributionin Mexico, Mexico, and Suchitepequez, Guatemala;C. entata from Chiapas, Mexico; and C. heiserifrom Durango, Sinaloa, and Jalisco in Mexico. Cyclanthera Schrader, a distinctive genus of NewWorld cucurbits in the tribe Cyclanthereae, can beeasily recognized either by its single, unfolded hor-izontal ringlike theca or by its oblique, explosivelydehiscent capsular fruits. At dehiscence, the seedsare thrown by a catapult-like placental arm. Similarexplosively dehiscent fruits are found in the closelyrelated Elateriopsis Ernst, Hanburia Seemann,Pseudocyclanthera Martinez Crovetto, and Ryti-dostylis Hooker & Arnott. Cyclanthera is a mod-erate-sized genus as far as the Cucurbitaceae isconcerned, including 35-40 species of small annualherbaceous vines. Study of collections in the courseof preparing a monograph of the genus has broughtto light five new species from Mexico, Guatemala,and Costa Rica, which are here described.Cyclanthera cogniauxii C. E. Jones & Kearns, sp. nov. TYPE: Costa Rica. Cartago: 12 km S of Tapanti, beside bridge over Rio Grande de Orosi, 6 Apr. 1969, 1,500 m, Lent 1573 (ho-lotype, F 1703275). Figure 1. Folia plus minusve 5-7 lobata; glandulae ad basim foliilaminae 2-6 parvulae; inflorescentiae masculae folia su-perantes; pedunculus communis masculus inventus solumad superum /3 florifer; corolla virella. Stem nodes pubescent to tomentose. Petioles gla-brous to puberulent, 10-30 mm long. Leaves broad-ly ovate to orbicular, somewhat 5-or 7-lobed, 4-12 x 5-12 cm, the central lobe triangular, 2-5 x3-7 cm, lateral lobes similar, becoming progres-sively smaller, the margins denticulate to coarselyUniversity, Fullerton,St. Louis, Missouri 63166-0299, U.S.A.dentate; upper surface glabrous, with veins glabrousto puberulent especially at juncture of petiole andbase of leaf; lower surface completely glabrous; glandsat base of leaf blade 2-6, very small. Tendrils bifid.Male inflorescences elongated, few-flowered, ra-cemes or panicles, 6-16 cm long, often longer thanthe leaves, with flowers confined to upper '/ of pe-duncle or less; pedicels glabrous to puberulent, 2-5 mm long; calyx tube 4-4.5 mm wide; calyx teeth5, very small to 1 mm long; corolla greenish white,7-10 mm wide; petals 5, 3-nerved, 2-3 x 2-3mm; anther capitulum 2-3 mm wide; column 2-2.25 mm long; pollen pentacolporate, 75-80 �mdiam. Peduncles of female flowers 6-10 mm long;style 1.5-2 mm long; stigma 1.5-2 mm wide; ovarylanceolate to ovate, 3-4 x 2-2.5 mm, the apexacuminate, with beak 1.5-2 mm; ovules 3-5. Fruit-ing peduncles 2.5-7 cm; fruit 15-20 x 10-15mm, the apex blunt; setae many, over entire fruit,1-6 mm long; placenta 5-7 mm long. Seeds 7-8x 4-5 x 1-1.5 mm. Cyclanthera cogniauxii is found in Costa Ricaalong the Central Cordillera at elevations between1,500 and 2,500 m. It is quite distinct and appearsto be only distantly related to C. steyermarkii Stan-dley and C. monticola Gentry. It can be readilyseparated from the former by the presence of glandsat the base of the leaf blade and by the position ofthe male flowers along the male inflorescence. Itcan be separated from the latter by the much longermale inflorescence, much larger male flowers, andby the presence of glands at the base of the leafblade. Cyclanthera cogniauxii is named for theeminent nineteenth-century authority on the familyCucurbitaceae and former monographer of the genusCyclanthera, Celestin Alfred Cogniaux (1877). Paratypes. COSTA RICA. Alajuela: "La Palma" deSan Ramon, 21-23 Aug. 1927, Brenes 5691 (F); be-tween Finca La Selva y San Rafael de Vara Blanca, Nslope Barva, 1,740 m, 23 June 1963, Jimenez 834 (F); NovoN 4: 373-380. 1994.