title: A new threatened species of Pandanaceae from northwestern Madagascar, Pandanus sermolliana.
abstract: Pandanus sermolliana Callmander & Buerki (Pandanaceae) is described from humid forests in the Galoka mountain chain in northwestern Madagascar. The new species can be easily distinguished from the other members of the genus it most closely resembles, P. insuetus Huynh and P. perrieri Martelli, by several morphological characters including drupes that are incompletely fused, with each of the dome-like carpels separated from the base of the pileus, and stigmas that are sub-vertical or rarely sub-horizontal, slightly spinescent, and raised on an incompletely united base. This distinctive species is rare and is classified as Critically Endangered based on IUCN threat criteria.
authors.affiliation: Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166-0299, USA.; Université de Neuchâtel, Laboratoire de Botanique Evolutive, Rue Emile-Argand 11, Case postale 158, 2009 Neuchâtel, Suisse.
authors.forename: Martin W
authors.initials: MW
authors.lastname: Callmander
authors.forename: Sven
authors.initials: S
authors.lastname: Buerki
authors.forename: Sebastien
authors.initials: S
authors.lastname: Wohlhauser