Cupressaceae

Juniperus navicularis Gand.

A small shrub to 2m that is restricted to coastal dune systems in southwestern Portugal and a small area of Spain. Tourism development, agricultural and forestry activities are the main threats.

Description

Taxonomic notes

This taxon is currently listed on the IUCN's Redlist under the name of Juniperus oxycedrus ssp transtagana. Recent range wide morphological and genetic studies indicate that it should be recognised as a distinct species that is more closely related to J. brevifolius from the Azores than to J. oxycedrus

Distribution

Southwestern Portugal and Spain. In Portugal it is mainly found around the Sado Estuary and the Setubal Peninsular with a few other isolated localities such as Alentejo and Algrave. In Spain it is found in Huelva and near Cadiz where there is a population estimated to consist of about 5000 individuals. The Huelva population is estimated to be about 500 individuals in two localities. The total area of occupancy is estimated to be less than 150km², based on recent observations and recent herbarium records. Its extent of occurrence in Protuagl is less than 8000km²; inclusion of the Spanish populations increases the EOO to more than 30000km².

Habitat and Ecology

Restricted to stable coastal dune systems in both Spain and Portugal at altitudes ranging from 5 to 220m a.s.l. Naturally associated species include Quercus lusitanica, Daphne gnidium, Arum neglectum and Chamaerops humilis. Many stands have been afforested with Eucalyptus and Pinus pinea.

Human Uses

No specific uses have been recorded although like other junipers, it produces essential oils in its leaves that may have pharmacological value.

Conservation Status

Global Status and Rationale

Currently this taxon is listed by the IUCN under the name J. oxycedrus var transtagana as Near Threatened. Although its Area of Occupancy is less than that required for Endangered, there has been some uncertainy about the extent of any ongoing decline due to urbanisation and other threats. The assessment needs to be revised and incorporate data published since 2011.

Global Threats

Urbanisation, tourist development, conversion of habitat for agriculture and/ or forestry have all impacted this species. While individuals may persist undr Pine or Eucalypt plantations, regeneration is poor and seed viability is low.

Conservation Actions

The coastal Juniper communities are are one of the priorities of the EU's Habitat Directive and Natura 2000. Additionally some stands are protected within regional parks. In Spain, J. navicularis is listed as Critically Endangered on the Spanish Redlist.

References and further reading

  1. Boratynski, A., W. Wachowiak, M. Dering, K. Boratynska, K. Sekiewicz, K. Sobierajska, A. Jasinska, M. Klimko, J. Montserrat, A. Romo, T. Ok, Y. Didukh (2014) The biogeography and genetic relationships of Juniperus oxycedrus and related taxa from the Mediterranean and Macaronesian regions. Botanical Journal of the Linnean Society 174:637-653.
  2. Castro MR, Ferreira Belo A, Afonso A & MA Zavattieri (2011) Micropropagation of Juniperus navicularis, an endemic and rare species from Portugal SW coast. Plant Growth Regul. 65:223–230
  3. Diez-Garretas, B., J. Perena & A. Asensi (2016) Morphological analysis, chorology and ecology of Juniperus navicularis Gand. in the Iberian Peninsula. Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology:DOI:10.1080/11263504.2016.1149118.
  4. Farjon, A. (2013) Juniperus oxycedrus var. transtagana. The IUCN Red List of Threatened Species 2013: e.T16348802A16348883. http://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T16348802A16348883.en. Downloaded on 19 July 2016.
  5. Franco. (1986) Cupressaceae. In: S. Castroviejo (ed.), Flora Iberica: plantas vasculares de la Peninsula Iberica e Islas Baleares. Vol.I: Lycopodiaceae - Papaveraceae, Real Jardin Botanico : Consejo Superior de Investigaciones Cientificas, Madrid.
  6. Moreno JC. (2008) Lista Roja 2008 de la flora vascular española [2008 Red list of Spanish vascular flora]. Madrid: Dirección General de Medio Natural y Política Forestal.
  7. Picchi S. (2008) Management of Natura 2000 habitats. 2250 *Coastal dunes with Juniperus spp. EuropeanCommission