Euphorbia papillaris (Boiss.) Raffaelli & Ricceri

Mokni, Ridha El, Barone, Giulio & Domina, Gianniantonio, 2024, The Euphorbia bivonae aggregate (Euphorbiaceae) in the Central Mediterranean area: First report of Euphorbia papillaris from Tunisia, Phytotaxa 669 (1), pp. 57-66 : 59

Euphorbia papillaris (Boiss.) Raffaelli & Ricceri in Webbia 42: 7 (1988)

≡ E. bivonae var. papillaris Boiss. in DC., Prodr. 15(2): 131 (1862), basion.

Type (lectotype designated by Raffaelli & Ricceri 1988: 8):— ITALY. Insula Favignana, prope Sicilia, 1829, Jan 53 (G-DC G00312037) (isotypes: K000911865, K000911865).

Phenology:—Flowering and fruiting plants were observed in Tunisia from late April; in Sicily, from November to April.

Distribution:— Euphorbia papillaris was previously considered endemic to northwestern Sicily (i.e. Zingaro and Mount Erice) and the Egadi Islands (see Bajona & Spadaro 2022). After recent field investigations and herbarium studies, we can state this species also occurs in Tunisia (Cap Bon) and Libya (Tripolitania and Cyrenaica) ( Figure 1 ).

Habitat and ecology in Tunisia:— Euphorbia papillaris in Tunisia is restricted to the eastern coastal of Haouaria (Nabeul governorate,Cap-Bon of Tunisia).It usually grows on limestone slopes,from 30to180 m elevation, accompanied by several thermophilous species of the maquis shrubland and the Mediterranean scrub ( Figure 4 ), such as Ambrosina bassii L., Daphne gnidium subsp. mauritanica (Nieto Fel.) Halda , Festuca coerulescens Desf. , Genista aspalathoides Lam. , Phillyrea latifolia L., Pistacia lentiscus L., Biscutella didyma L. s.l., Cytisus infestus subsp. intermedius (Salzm. ex C.Presl) Cristof. & Troìa , Daucus carota subsp. fontanesii Thell. , Erica arborea L., Erodium botrys (Cav.) Bertol. , Filago gallica L., Galium verrucosum Huds. , Helichrysum stoechas subsp. barrelieri (Ten.) Nyman, Hyoseris radiata L., Hypericum humifusum L., Leontodon tuberosus L., Ononis hispanica subsp. ramosissima (Desf.) Förther & Podl. , Paronychia echinulata Chater , Quercus coccifera L., Q. ilex subsp. ballota (Desf.) Samp. , Ranunculus paludosus Poir. , Rubus ulmifolius Schott , Ruscus hypophyllum L., Schoenus nigricans L., Sedum tuberosum Coss. & Letourn. (Algerian-Tunisian endemic), Simethis mattiazzii (L.) Sacc., Smilax aspera L., Stachys arvensis (L.) L., Thymelaea hirsuta (L.) Endl., Tuberaria guttata (L.) Fourr., T. lipopetala (Murb.) Greuter & Burdet , and Tulipa pumila Moench

Figures

FIGURE 1. Revised localities of Euphorbia bivonae (green dots), E. tunetana (yellow dots), E. melitensis (light blue dots), and E. papillaris (red dots).

FIGURE 4. Euphorbia papillaris in Tunisia. A. Habit and habitat within rocky slopes in Djebel Haouaria; B. Details of juvenile branches and leaves; C–E. Details of inflorescences with typical verrucose capsules. Photographs by R. El Mokni.