Phenology of Zamia boliviana (Zamiaceae), a threatened species from a seasonally dry biodiversity hotspot in South America

Abstract

Dioecy, a character common to all cycads, requires obligatory outcrossing. The absence of potential reproductive mates of the opposite sex renders individuals effectively sterile. Therefore, reproductive synchrony is essential for the reproductive success of cycads. Here, we describe the reproductive phenology, morphology, and lifespan of strobili of Zamia boliviana (Cycadales, Zamiaceae), an endemic

Temporal shifts in reproductive phenology of cycads: a comparative study in Ceratozamia

“…Although the number of pollen strobili decreases during the year, some individuals continue to complete their ontogenetic development until reaching the OP phase. This disparity has been described in other cycad species (Martínez-Domínguez et al 2018a;Segalla et al 2021), which could be related to dynamics involving insect pollinators. We have observed individuals of Pharaxonotha tenuis (Santiago-Jiménez, 2019) in the last polliniferous strobili of a population in July, and up to four generations of insect pollinators during a year in populations of C. tenuis.…”

“…This observed pattern in Ceratozamia differs from that recorded in species of other cycad genera -e.g., Zamia boliviana (Brongn.) A.DC., in which R and OP occur between August and November and maturation of seeds was recorded during the dry season (Segalla et al 2021). Our results revealed that, in addition to precipitation, the temperature is also more constant during the months of the seed development in ovulate strobili.…”

“…Because cycads are long-lived and have reproductive structures with long-lifespan, their phenology has been little explored (Stevenson 1981;Clark and Clark 1987;Tang 1990;Ornduff 1991). Recently, phenological data have been used for describing lifespans, analyzing patterns from a phylogenetic context, and synchrony among events (Lopez-Gallego and O'Neil 2010;Martínez-Domínguez et al 2018aSegalla et al 2021). Living collections and herbarium specimens have been used as a resource for the systematic study of phenology (Calonje et al 2011;Griffith et al 2012;Clugston et al 2016).…”

“…Recently, cycad phenology has been approached from phylogenetic and taxonomic perspectives (Clugston et al 2016;Martínez-Domínguez et al 2018a;Segalla et al 2021). In Mexico, these types of studies are promising due to the occurrence of three genera --namely, Zamia L., Dioon Lindl., and Ceratozamia Brongn.…”