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| Leptocereus velozianus Clase, Y.Encarn., Peguero & Majure, in Majure, Encarnación, Clase, Peguero, Ho & Barrios, 2021. Photos taken by L.C. Majure. |
Abstract
The Antillean genus Leptocereus represents an in-situ radiation among the Greater and Lesser Antilles of 19 currently recognized species. Extensive fieldwork carried out in the Dominican Republic over recent years has revealed that the species limits of Leptocereus of Hispaniola are more complex than previously thought. There are four currently recognized species that occur on the island, L. demissus, L. paniculatus, L. undulosus and L. weingartianus. We evaluate species limits in this group based on DNA sequence data and phylogenetic analysis, morphological characters and a survey of herbarium specimens from across Hispaniola. Based on our analyses, it is clear that at least five species occur on the island of Hispaniola, with the new species from Sierra de Bahoruco, L. velozianus, described here. We provide an identification key, distribution maps and photographic plates for all species on Hispaniola based on our own fieldwork and the study of herbarium specimens. The description of yet another species of Leptocereus on Hispaniola reiterates the importance of the poorly studied, but yet biodiverse, seasonally dry tropical forest in the Antilles.
Keywords: Biodiversity, Greater Antilles, plastome phylogeny, Seasonally Dry Tropical Forest
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| Leptocereus velozianus Clase, Y.Encarn., Peguero & Majure. A–C stems showing crenate margins D, E cross sections showing 4-5 ribbed stems, also showing large crystals in the parenchyma F day old flower showing rounded external tepal apices and spiny pericarpel, and G immature fruit showing spiny pericarpel and remnant floral tube. A from Majure 7842, and B–F from Majure 7843. |
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| Leptocereus velozianus Clase, Y.Encarn., Peguero & Majure. A small tree habit of L. velozianus alongside T. Clase for scale B, C arching branches and spine color D trunk and bark E growing stem showing white spines as they mature F spiny, immature fruit G colliculate-pitted seed, and H stems with immature fruit, showing crenate rib margins. A, D, F, G from Majure 7851 B, C, H from Majure 7843, and E from Majure 7842. Photos taken by L.C. Majure. |
Leptocereus velozianus Clase, Y.Encarn., Peguero & Majure, sp. nov.
Diagnosis: Differing from both L. weingartianus and L. demissus by the white young spines (vs. yellowish spines) and larger stem diameter (up to 3.7 cm in diameter in L. velozianus). Differing from L. demissus by the erect, primary trunk rather than the sprawling growth form, and oblong hypanthium in L. velozianus rather than obconic hypanthium as in L. demissus.
Etymology: The specific epithet, “velozianus” is given honoring the Dominican botanist Alberto Veloz, who is the Head and Curator of the Herbarium JBSD of the “Dr. Rafael M. Moscoso” National Botanical Garden of Dominican Republic. For 27 years, Veloz has dedicated his life to the study of the Hispaniolan flora and has conducted extensive fieldwork across the island, with many collections from the Sierra de Bahoruco, where this new species was found. Together with other botanists he has collected over 10,000 specimens and has published several papers on the flora in national and international journals. His publications have included different approaches, such as floristics, taxonomy, ecology and conservation. Veloz has also contributed to the formation of young botanists by involving students as part of the staff in the herbarium JBSD and through fieldwork.
Lucas C. Majure, Yuley Encarnación, Teodoro Clase, Brígido Peguero, Kelly Ho and Duniel Barrios. 2021. Phylogenetics of Leptocereus (Cactaceae) on Hispaniola: Clarifying Species Limits in the L. weingartianus complex and A New Species from the Sierra de Bahoruco. PhytoKeys. 172: 17-37. DOI: 10.3897/phytokeys.172.59497
