EPPO Global Database

Alien flora of Rhodes island (Greece)

The alien flora of Greece includes 272 taxa of which 250 are considered established. Here the authors present the alien flora of the Island of Rhodes which is the largest of the Dodecanese islands located in the Southeast Aegean region. Rhodes Island is 1400 km² with a semi-arid Mediterranean climate (short mild wet winter and a long hot dry summer). The alien flora of Rhodes comprises 114 taxa of vascular plants and marine algae representing 55 families. Of the 101 vascular plant taxa 78 are established (naturalised) and 23 are casual. The majority are herbaceous species (59 taxa) with a smaller number of trees (26 taxa) and shrubs (15 taxa). For all alien taxa recorded the majority originate from the Americas. In 1987 a survey of Rhodes Island identified 40 naturalised vascular plant species – whereas this present study has identified 78 which corresponds to a 95 % increase in naturalised vascular plants. As a result of the current study 27 alien flora were recorded for the first time on the island of Rhodes (Table 1). Of these 27 taxa, 14 are new additions to the flora of Greece and one – Phymosia umbellata - is recorded for the first time in Europe. The threat to local biodiversity is particularly high in island ecosystems and the threat to the native flora of Rhodes Island is no exception. Some of the alien flora of Rhodes have been shown to decrease the abundance of native species. Arundo donax, Carpobrotus edulis (EPPO List of Invasive Alien Plants), Ipomoea indica, Lantana camara and Oxalis pes-caprae (EPPO List of Invasive Alien Plants) have all been shown to outcompete native species. Other alien species on the island such as Ailanthus altissima (EPPO List of Invasive Alien Plants) alter the soil chemistry while Agave americana competes indirectly with native plant species for light, nutrients and space. All of the alien taxa presented in the current study should be closely monitored for both their spread on the island and impacts on native species. Management practices should be implemented for the most invasive of these species.

Table 1. First alien flora records for Rhodes Island (Greece). Species names in bold represent the first record of the species in Greece.

Species	Family	Native range	EPPO countries*
Justicia adhatoda	Acanthaceae	S. Asia	CY, GR, MT
Yucca gloriosa	Agavaceae	Americas	GB, GR, ME, PT
Nothoscordum gracile	Alliaceae	N. America	GR, PT
Amaranthus cruentus	Amaranthaceae	Americas	GR, HU, PL, UA
Narcissus papyraceus	Amaryllidaceae	Mediterranean	native EPPO region
Thevetia peruviana	Apocynaceae	S. Africa	CY, GR
Zantedeschia aethiopica	Araceae	S. Africa	FR, GB, GR, IE, IT, PT
Washingtonia filifera	Arecaceae	N. America	CY, IT, GR
Bidens pilosa	Asteraceae	Americas	CY, ES, FR, GR, IT
Senecio angulatus	Asteraceae	S. Africa	ES, FR, GR, IT
Jacaranda mimosifolia	Bignoniaceae	S. America	ES, GR
Austrocylindropuntia subulata	Cactaceae	S. America	IT, ES, GR
Bauhinia variegata	Caesalpiniaceae	SE. Asia	GR, PT
Caesalpinia gilliesii	Caesalpiniaceae	S. America	ES, GR
Erythrina lysistemon	Fabaceae	Africa	GR, PT
Freesia leichtlinii subsp. alba	Iridaceae	S. Africa	GR
Brachychiton populneus	Malvaceae	Australia	ES, GR
Hibiscus rosa-sinensis	Malvaceae	E. Asia	GR, PT
Phymosia umbellata	Malvaceae	C. America	GR
Albizia julibrissin	Mimosaceae	Asia	CY, GR, PT
Ficus microcarpa	Moraceae	Australia	IT, GR
Pittosporum tobira	Pittosporaceae	Asia	GB, GR
Cortaderia selloana	Poaceae	S. America	Widespread
Pyracantha coccinea	Rosaceae	Europe	native EPPO region
Myoporum tenuifolium	Scrophulariaceae	SE Asia	ES, GR, IT, PT
Tropaeolum majus	Tropaeolum	S. America	Widespread
Lantana camara	Verbenaceae	S. America	ES, IT, GR

* Records where the species has been recorded either as a casual or established species. Records of species have been checked in the Q-bank database, as well as the DAISIE, NOBANIS and PQR databases.

Sources

Galanos CJ (2015) The alien flora of terrestrial and marine ecosystems of Rodos island (SE Aegean), Greece. Willdenowia 45(2), 261–278.