Rouya polygama

Family: Apiaceae
Scientific name: Rouya polygama (Desf.) Coincy
Synonym: Thapsia polygama Desf.
Common name: Firrastrina bianca
English name: -
Brief description: This herbaceous perennial plant is 15-30(50) cm high. Stems are generally ascendant and willowy. The lower leaves are bipinnate, with the second-order segments generally tridid or pinnatipartite. The flowers, in umbrella-like clusters, have white petals, and the fruit is an achene about 8-9-mm long, with undulated wings about 2 mm long (Pignatti, 1982; Bacchetta, 2001; Gamisans & Jeanmonod, 2007).
Biology and ecology:

Rouya polygama flowers in June and July and bears fruit in September and October (Tutin 1968; Pignatti, 1982; Bacchetta, 2001).

Dispersion takes place via winged achenes, suitable for wind dispersion; there is as yet no information on the vitality and germination capacity of diaspores (Santo et al., 2013).

It is a psammophilous, sun-loving species, typical of coastal dunes, especially in retro-dunal depressions on consolidated sands. Rarely, along Sardinia’s east-central coast, it can be found on semi-stable dunes and rocky seaside slopes. (Bacchetta, 2001).

Global distribution:

Rouya polygama is found in the south-western Mediterranean in Sardinia, Corsica (Paradis & Géhu, 1992; Pozzo di Borgo & Paradis, 2000), Algeria (Quezel & Santa, 1963) and Tunisia (Pozzo di Borgo & Paradis, 2000). In Italy this species is found only in Sardinia (Santo et al., 2013).

Habitat in Sardinia:

The plant communities in which this species is found are those of the Crucianellion maritimae alliance, which include the habitat of community interest “Crucianellion maritimae fixed beach dunes” (2210) and secondarily, the priority habitat “Coastal dunes with Juniperus ssp. (2250*)”, pursuant to Dir. 43/92/CEE “Habitat”.

General notes:

Rouya polygama is a species of great systematic, phyto-geographic, and ecological interest; it is listed as globally endangered (EN) according to IUCN criteria (Santo et al., 2013) and is included in the Washington Convention (CITES), Annex I of the Bern Convention, and Annex II of the “Habitat” Directive (92/43/EEC).

It is present in 4 Sites of Community Importance (SCI) in Sardinia and in 3 of Sardinia’s International Plant Areas (IPAs) (Blasi et al., 2010; Santo et al., 2013).

Species factsheet by Stefania Pisanu and Rossella Filigheddu UNISS

Main references:

• Bacchetta G., 2001 – Rouya polygama (Desf.) Coincy. In: Pignatti S., Menegoni P., Giacanelli V. (Eds.), Liste Rosse e Blu della Flora Italiana. Anpa, Roma.

• Blasi C., Marignani M., Copiz R., Fipaldini M., Del Vico E. (Eds.), 2010 – Le Aree Importanti per le Piante nelle Regioni d’Italia: il presente e il futuro della conservazione del nostro patrimonio botanico. Progetto Artiser, Roma.

• Filigheddu R., Farris E., Pisanu S., Navone A., 2011 – Analisi geobotaniche nell’Area Marina Protetta di Tavolara-Punta Coda Cavallo (Sardegna NE) a supporto della gestione della biodiversità. Studi Trent. Sci. Nat., 89: 113-135.

• Gamisans J., Jeanmonod D., 2007 - Flora Corsica. Edisud, Aix-en-Provence.

• Pignatti S., 1982 – Flora D’italia, Vol. II. Edagricole, Bologna.

• Pozzo Di Borgo M.L., Paradis G., 2000 – Inventaire des stations naturelles et comptage du nombre d’individus de l’espéce rare et protégée Rouya polygama (Apiaceae) en Corse. Bull. Soc. Bot. Cent. Ouest, Nouvelle Série, 31: 3-20.

• Quezel P., Santa S., 1963 – Nouvelles Flores de l’Algerie et des régions désertiques méridionales. Cnrs Ed., Paris.

• Santo A., Fenu G., Bacchetta G., 2013. Rouya polygama (Desf.) Coincy. Schede per una Lista Rossa della Flora vascolare e crittogamica Italiana. Informatore Botanico Italiano, 45 (1): 115-193.

• Tutin T.G., 1968 – Rouya Coincy. In: Tutin T.G., Burges N.A., Chater A.O., Edmondson J.R., Heywood V.H., Moore D.M., Valentine D.H., Walters S.M., Webb D.A. (Eds), Flora Europaea. Vol. 2: 370. Second Edition, Cambridge, University Press. 151 Pp.