Distribution and population characteristics of the Cucumber Tree ( Dendrosicyos socotranus Balf.f.)
- PDF / 6,076,014 Bytes
- 12 Pages / 595.276 x 790.866 pts Page_size
- 67 Downloads / 150 Views
SOCOTRA BIODIVERSITY RESEARCH AND NATURE CONSERVATION
Distribution and population characteristics of the Cucumber Tree (Dendrosicyos socotranus Balf.f.) Hana Habrová1 · Petr Vahalík2 · Karel Drápela2 · Abdulwahab Saad Saeed Ali3,4 Received: 23 December 2019 / Accepted: 26 June 2020 © Accademia Nazionale dei Lincei 2020
Abstract We conducted a study throughout Socotra Island (Yemen) to investigate the distribution, population structure and regeneration potential of the endemic and threatened tree species Dendrosicyos socotranus, the Cucumber Tree. In total, 163 live trees (excluding seedlings) were found in all (24) investigated locations, covering an area of 96 km2. The height, stem circumference, fertility and coordinates of each tree were measured and data regarding the ecotope, land cover and natural regeneration were recorded. We estimated that there could be more than 6400 Cucumber Tree individuals among the populations on Socotra Island. The majority of the trees occur in the “high Shrubland with succulents” and “wadi” land cover classes. In general, the fertility of the trees is good, and natural regeneration occurred in 77% of the locations with adult trees; it was found that 16% of the individual trees regenerated. Our study, collecting data on the regeneration of the species and estimating the size of local populations for the first time, can be used for local conservation and future monitoring of this important, endangered Socotran endemic. Keywords Socotra · Yemen · Woody Cucurbitaceae · Land cover · Dendrosicyos socotrana · Fertility · Regeneration
1 Introduction Members of the Cucurbitaceae family are usually characterised as perennial herbs, with prostrate or climbing growth habits and bicollateral vascular bundles (Heywood et al. 1993). One exception is the bottle-trunked succulent tree Dendrosicyos socotranus Balf.f., originally described as Dendrosicyos socotrana (Balfour 1888) and recently This paper belongs to a Topical Collection “Twenty years of biodiversity research and nature conservation in the Socotra Archipelago” edited by Fabio Attorre and Kay Van Damme, conceived at the 18th Friends of Socotra Conference, 26–29 September, 2019, Orto Botanico di Palermo, Palermo, Italy”.
renamed to fit the grammatical gender (IPNI 2020; Renner and Schaefer 2016). The tree belongs to a monospecific genus placed in the Cucurbitoidae subfamily and Coniandreae tribe; it is restricted to the Socotra archipelago where it has been estimated to have diverged from its closest relatives some 14 (8–19) million years ago (Renner and Schaefer 2016). The species is characterized by typical swollen waterstoring trunk (Miller 2004), pendulous branches and absent tendrils (Olson 2003). It is monoecious with long yellow flowers forming tubular hypanthium, solitary or in small fascicles, and the male flowers have three stamens. The fruits are ellipsoid, smooth, and green and turn brick-red when ripe (Balfour 1888; Olson 2003).
* Hana Habrová [email protected] Petr Vahalík [email protected] Karel Drápela drap
Data Loading...
