J Syst Evol ›› 2023, Vol. 61 ›› Issue (5): 827-842.DOI: 10.1111/jse.12925

• Research Articles • Previous Articles     Next Articles

An integrative taxonomic study of Santolina (Asteraceae) from southern France and north-eastern Spain reveals new endemic taxa

Antonio Giacò1*, Lucia Varaldo2, Gabriele Casazza2, Daniele De Luca3, Paolo Caputo3, Marco Sarigu4, Gianluigi Bacchetta4, Llorenç Sáez5, and Lorenzo Peruzzi1   

  1. 1 PLANTSEED Lab, Department of Biology, University of Pisa, Via Derna 1, 56126 Pisa, Italy;
    2 Department of DISTAV, University of Genoa, Corso Europa 26, 16132 Genoa, Italy;
    3 Department of Biology, University of Naples"Federico II", via Cupa Nuova Cintia, 21, 80126 Naples, Italy;
    4 Department of Life and Environmental Sciences, University of Cagliari, V. le S. Ignazio da Laconi 11-13, Cagliari, Italy;
    5 Department BABVE(Systematics and Evolution of Vascular Plants, associate unit to CSIC), Faculty of Biosciences, Autonomous University of Barcelona, 08193 Bellaterra Barcelona, Spain
    *Author for correspondence. E-mail:antonio.giaco@phd.unipi.it
  • Received:2022-07-29 Accepted:2022-10-21 Online:2022-10-31 Published:2023-09-01

Abstract: Santolina is a clear example of a genus lying in an alpha-taxonomic status, with species accepted only based on qualitative morphological descriptions. In particular, taxonomic issues still need to be resolved for Santolina populations from southern France and north-eastern Spain, and so, we carried out an integrative taxonomic study involving morphometrics, cypsela morphometrics, niche overlap, and phylogenetic analysis based on six plastid markers (trnH-psbA, trnL-trnF, trnQ-rps16, rps15-ycf1, psbM-trnD, and trnS-trnG). Our results revealed that the current taxonomic circumscription is not adequate. In particular, the Santolina populations at the foothills of eastern Pyrenees, previously included in the variability of Santolina benthamiana, have to be considered as a distinct species, namely, Santolina intricata. In addition, despite their high phylogenetic relatedness, S. benthamiana s.str. and Santolina ericoides can still be considered as distinct species due to clear morphological and ecological differentiation. Finally, we demonstrated that three different subspecies can be recognized in Santolina decumbens, a species endemic to Provence. For one of these subspecies, due to its extremely restricted distribution range, conservation issues are pointed out.

Key words: Anthemideae, image analysis, Mediterranean Basin, molecular systematics, morphometrics, niche overlap