80 years of research on planarians (Platyhelminthes, Tricladida) from Sardinia, Italy: an annotated checklist Author Stocchino, Giacinta Angela text Zootaxa 2018 2018-12-20 4532 4 539 552 journal article 27733 10.11646/zootaxa.4532.4.5 38d5db9a-4c71-408d-84d2-5b98fd8afa0d 1175-5326 2615649 807B317B-D883-439F-97B9-B0C0F09D9666 Dugesia sicula Lepori, 1948 Dugesia sicula was first reported for Sardinia on the basis of fissiparous populations, in which a certain percentage of individuals underwent a sexualization process, from 12 Sardinian localities, including 2 small nearby islets (spring and wells on the Tavolara Island Protected Area and watercourses on the S. Antioco Island) (Pala et al ., 1995) ( Fig. 1 ). After several years other fissiparous populations were found in two other watercourses, one in the northwestern Asinara Island National Park (Rio d’Auteri reservoir) ( Stocchino, 2003 ) and another in southeastern Sardinia (Fiume Quirra) (M. Pala, pers. comm.) ( Fig. 1 ). All Sardinian populations showed a coastal distribution with a high degree of tolerance to variations in environmental factors, especially temperature and watercourses hydrological regime e.g. temporary water (Pala et al ., 1995; G.A. Stocchino, pers. obs.). Dugesia sicula has a pan-Mediterranean geographic range where it is mostly represented by fissiparous populations with only a few sexual populations being present in Mallorca, Algeria , Tunisia and Israel . Two mixed populations, including both sexual and fissiparous individuals, were reported from Sicily (Stocchino & Manconi 2013 and references therein). A recent reassessment of the taxonomic status of D. biblica Benazzi & Banchetti, 1973 from Israel and Turkey , based on morphological and molecular studies, considered this species to be a junior synonym of D. sicula ( Solà et al ., 2015 ) . As for karyology, numerous studies confirmed a diploid condition for sexual populations with a chromosome complement of 2n = 18; n = 9, and a triploid condition for fissiparous populations with a chromosome complement of 3n = 27; n = 9 + 1-5 B-chromosomes (see Stocchino et al ., 2012 and references therein). Among Dugesia species, the haploid complement of nine chromosomes of D. sicula is shared with only five other species: D. maghrebiana Stocchino et al ., 2009 , from North Africa; D. arabica Harrath & Sluys, 2013 from Yemen ; D. aethiopica Stocchino et al ., 2002 and D. afromontana Stocchino & Sluys, 2012 from the Afrotropical region; D. bifida Stocchino & Sluys, 2014 from Madagascar ( Stocchino et al ., 2002 , 2004 , 2009, 2012, 2014; Harrath et al ., 2013 ). Although D. sicula is extremely widespread, a molecular analyses on many fissiparous populations from its entire distributional range revealed a remarkable pattern of low interpopulation genetic variability, which was interpreted as the result of recent anthropochore colonizations after triploidization of sexual diploid populations ( Lazaro et al ., 2009 ).