Palmarola Bejerano, Alejandro

The population of Leptocereus scopulophilus is small and barely occupies 3.500 m2 in the southeast side of Pan de Matanzas. These unique features may require a flowering strategy different from that of most columnar cacti with larger and widespread populations. In this paper, the production of flowers, the availability of flower buds, flowers and fruits; the volume and concentration of nectar; and the energy output of this Cuban endemic species were study. Additionally, the pollination effectiveness and the likelihood of cross-pollination were estimated. L. scopulophilus starts flowering in the second half of the dry season (February) and runs through the beginning of the rainy season (June) but most flowers are produced from March to May. Most plants open an average of one flower per night. Although, the number of blooming plants increase up to April the intensity of flower production in the population is always less than 50%. Nectar production and concentration do not vary significantly. The flowers may produce up to 0,76 mL of nectar per night and allocate more than 1 kJ in the nectar. The success of the pollination increases along the course of the season up to 45%. In general, the flowering strategy of L. scopulophilus is similar to that of other columnar cacti from dry ecosystems.

The genus Leptocereus comprises about a dozen species endemic to the Caribbean. The majority of these species are endemic to Cuba and all of them are threatened by extinction. In this paper, the flowers of L. scopulophilus are characterized considering the inner diameter of the perianth, the deep of the nectar chamber and the length of the floral tube. Flower development is described taking into account the anthesis, and the production and concentration of nectar. The mating system of this species is determined and flower visitors and pollinators are identified. The diameter inner of perianth is 1,84 cm, the length of floral tube is 2,16 cm and the deep of nectar chamber is 0,62 cm. The anthesis occurs in the afternoon around 18:30, the production of nectar begin among 21:00 and 22:00 and is extend until 10:00 of the next day, while the nectar concentration vary among 19,4 % and 16,2 % of sacarose. L. scopulophilus is exclusively out crossing and self-incompatible species. The flowers have a syndrome of chiropterophillous pollination, however, 14 visiting species have been identified. Only the nocturnal pollination by Monophyllus redmani bat is successful.

Leptocereus wrightii León es quizás la especie de Cactaceae más amenazada de Cuba. Berazaín & al.(2005) la refieren en Peligro Crítico pero ha llegado a considerarse Extinta en la naturaleza (Gutiérrez 2005) o Extinta (Borhidi & Muñiz 1983).

Los representantes del género Magnolia L. (Magnoliaceae) se distribuyen en el sureste de Asia y desde el sureste de América del Norte hasta el sur de Panamá y las Antillas Mayores (Treseder 1978, Callaway 1994). Hasta el momento para Cuba han sido reportadas tres especies de Magnolia con ocho taxones infraespecíficos (Imchanitskaja 1991). Estas especies son endémicas y se distribuyen en Cuba Central y Oriental. Generalmente, las especies cubanas de Magnolia se desarrollan por encima de los 700 msm en bosques pluviales montanos o bosques nublados, sobre suelos ácidos o lateritas (Bisse 1988, Imchanitskaya 1991). En similares condiciones ecológicas viven las magnolias de La Española y Puerto Rico (Alain 1983, 1985) mientras que para Jamaica no se reportan magnolias nativas (Adams 1972).