Leaf anatomical features and their implications for the systematics of dragon's blood, Croton section Cyclostigma (Euphorbiaceae)

Establishing species limits in clades in Croton using characters from external morphology and common molecular markers has proved cumbersome, especially in Croton section Cyclostigma, a group of 50 Neotropical arborescent species commonly known as dragon's blood. Given this, we explored leaf an...

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Detalles Bibliográficos
Autores: Feio, Ana Carla, Meira, R.M.S.A., Riina, Ricarda
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/248486
Acceso en línea:http://hdl.handle.net/10261/248486
Access Level:acceso abierto
Palabra clave:Colleters
hypodermis
idioblasts
Nectaries
non-articulated laticifers
nonsecretory trichomes.
Descripción
Sumario:Establishing species limits in clades in Croton using characters from external morphology and common molecular markers has proved cumbersome, especially in Croton section Cyclostigma, a group of 50 Neotropical arborescent species commonly known as dragon's blood. Given this, we explored leaf and shoot apex anatomical characters for their utility in distinguishing species or groups of species in this section. We analysed 90 specimens belonging to section Cyclostigma and 14 specimens from related groups (sections Adenophylli, Cupreati and Sampatik), recording and describing 45 qualitative leaf characters. These characters were assembled into a matrix and analysed using statistical clustering methods based on similarity. Our results show that trichomes are one of the most diverse and variable anatomical features among the studied specimens. Novel anatomical features for Croton include the presence of a hypodermis and two previously unreported types of non-glandular trichomes. Although we did not detect a single anatomical character uniting section Cyclostigma, combinations of anatomical characters were useful to establish species limits and taxonomic identities within this section.