Two major lineages of beetles inhabit cycad cones in the New World: weevils (Curculionoidea) in the subtribe Allocorynina, including the genera Notorhopalotria Tang and O'Brien, Parallocorynus Voss, Protocorynus O'Brien and Tang and Rhopalotria Chevrolat, and beetles in the family Erotylidae, including the genus Pharaxonotha Reitter. Analysis of the 16S ribosomal RNA (rRNA) mitochondrial gene as well as cladistic analysis of morphological characters of the weevils indicate four major radiations, with a probable origin on the cycad genus Dioon Lindl. and comparatively recent host shifts onto Zamia L. Analysis of the 16S rRNA gene for erotylid beetles indicates that an undescribed genus restricted to New World Ceratozamia Brongn. is the most early-diverging clade, and this lineage is sister to a large radiation of the genus Pharaxonotha onto Zamia, with apparent host shifts onto Dioon and Ceratozamia. Analysis of beetles are in accord with current models of continental drift in the Caribbean basin, support some proposed species groupings of cycads, but not others, and suggest that pollinator type may impact population genetic structure in their host cycads.

Variation in plant reproductive success is affected by ecological conditions including the proximity of potential mates. We address the hypothesis that spatial distribution of sexes affects female reproductive success (RS) in the dioecious cycad, Zamia portoricensis. Are the frequencies of males, operational sex ratios, and distances to the nearest mate associated with RS in females? We studied the spatial distribution of sexes in two populations in Puerto Rico and compared RS of target females with the number of males and operational sex ratios. Population structure suggests regular successful recruitment. Adults, males, and females were randomly distributed with respect to one another. Reproductive success of females was highly variable, but was higher in neighborhoods with more males than females and generally decreased with increasing distance to the nearest male, becoming statistically significant beyond 190 cm. This possible mate-finding Allee effect indicates that pollinator movement among plants may be limited for this mutually dependent plant-pollinator interaction. Yet being close to male plants is a matter of chance, perhaps a factor generating the high intra-population genetic diversity in Z. portoricensis.

This is the first report of the occurrence of wild Zamia pumila L. Zamiaceae populations on various volcanic substrates in the piedmont area of south central Puerto Rico. Data acquisition and its field confirmation were possible after the identification of toponymic names in old and current maps, and historic documents of the island in which one of the indigenous names for the genus (marunguey [marungüey] or marungueyes) has been used for naming some localities. These preliminary data have deep implications for paleo- and neoethnobotanical research, and for population ecology of the species in Puerto Rico, because they expand the traditionally accepted range for the species on the island. Zamia has been described as one of the main food plants among pre- and post-Columbian inhabitants in two islands of the Greater Antilles, Hispaniola and Puerto Rico, where the most sophisticated pre-Columbian society of the Antilles, the Taínos, emerged. Our findings suggest that Zamia might have been more available to humans, as a food source, than previously thought.

Antilles has been registered for Cuba (González-Géigel 2003). In Puerto Rico, three Zamia species have been recognized (Acevedo and Strong 2005; Axelrod 2011; Meerow et al. 2012). Zamia erosa Cook and Collins Zamiaceae is widely distributed across the northern limestone region, where its abundance ranges from rare to locally dominant. The other two species (Z. pumila and Z. portoricensis Urb Zamiaccae) are distributed along interrupted, metamorphosed limestone (marble), and serpentine areas of south-central and southwestern Puerto Rico. They are geographically separated from Z. erosa by the metamorphic volcanic rock of the Cordillera Central (Figure 1). During the last 8 years, archaeological findings in Puerto Rico (including Vieques island), Dominican Republic, Cuba, Saba, Trinidad and Aruba have consistently revealed the importance of Zamia for the pre-Columbian inhabitants of these islands