The Euphorbia bivonae aggregate (Euphorbiaceae) in the Central Mediterranean area: First report of Euphorbia papillaris from Tunisia Author Mokni, Ridha El 0000-0003-3849-1039 Monastir University, Laboratory of Botany, Cryptogamy and Plant Biology, Faculty of Pharmacy of Monastir, Avenue Avicenna, 5000 - Monastir, Tunisia. & Carthage University, IRESA, Laboratory of Forest Ecology, National Research Institute of Rural Engineering, Water and Forests, 2080 - Ariana, Tunisia. ridha.elmokni@fphm.rnu.tn Author Barone, Giulio 0000-0002-6345-3117 University of Palermo, Department of Agricultural, Food and Forest Sciences, Viale delle Scienze, bldg. 4, 90128 Palermo, Italy. giulio.barone01@unipa.it Author Domina, Gianniantonio 0000-0003-4184-398X University of Palermo, Department of Agricultural, Food and Forest Sciences, Viale delle Scienze, bldg. 4, 90128 Palermo, Italy. gianniantonio.domina@unipa.it text Phytotaxa 2024 2024-10-17 669 1 57 66 https://doi.org/10.11646/phytotaxa.669.1.6 journal article 10.11646/phytotaxa.669.1.6 1179-3163 14519915 Euphorbia tunetana (Murb.) Vierh. ex Buxb. in Verh. Zool.- Bot. Ges. Wien 76: 43 (1927) [«1926»] ≡ Euphorbia bivonae subsp. tunetana Murb. in Acta Univ. Lund. 35(3): 17 (1899) , basion. Type ( lectotype designated by Simon & Vicens 1999: 586 ):— TUNISIA . “Université d’Alger, Herbier de l’Afrique du Nord, Euphorbia bivonae , ssp. tunetana Murbeck , Tunisie: Bou-Hedma, 26 April 1884 , Doumet s.n. ” (MPU008008!). Notes :—The protologue of E. tunetana reports several localities from Tunisia and one from Algeria ( Domina & El Mokni 2019 ). Simon & Vicens (1999) designated as Lectotype a specimen from southern Tunisia. The large part of current contributions ( POWO 2024 ) considers this taxon a subspecies of E. bivonae . According to the variability observed among the other species of this group we judge more opportune to consider this taxon at species rank in accordance with the treatment reserved for the other taxa of this group. We believe, however, that further morphological and/or molecular studies are appropriate to better clarify the taxonomic relationships between those taxa. FIGURE 1. Revised localities of Euphorbia bivonae (green dots), E. tunetana (yellow dots), E. melitensis (light blue dots), and E. papillaris (red dots). Phenology :—Flowering and fruiting plants were observed from the end of February to late April(–May). Distribution :—This species occurs in Algeria , Tunisia and Libya ( Figure 1 ). Habitat and ecology in Tunisia :— Euphorbia tunetana is a chasmophytic suffrutex that grows on calcareous rocky slopes ( Figure 3 ), mainly with Ferula vesceritensis Batt. (endemic to the same chorological area), Teucrium alopecurus de Noé (endemic to Tunisia), T. ramosissimum Desf. (Moroccan-Algerian-Tunisian endemic), Galium petraeum Coss. (Algerian-Tunisian endemic), Centaurea microcarpa Batt. (Algerian-Tunisian endemic), Oreobliton thesioides Durieu & Moq. (Algerian-Tunisian endemic), Reseda alphonsi Müll. Arg. (Algerian-Tunisian endemic), Sedum rubens L., S. sediforme (Jacq.) Pau , Senecio flavus (Decne.) Sch. Bip.