taxonID	type	description	language	source
294695109F4AFFB5FCEEFD46FDD5F08E.taxon	description	Hence, there is incongruence between the mitochondrial history and the nuclear and morphological accounts. In some cases, a potentially high degree of genetic variation may only be reflected by recondite morphological traits (according to Kucera and Darling 2002) that are not evident at first sight. Sibling species often have minor morphological differences that are only noticed once species are recognized for other reasons — such as karyological data or molecular evidences. The species that fit this profile are known as pseudo-cryptic (Knowlton 1993), and this may be the case for Corsican and Sardinian D. benazzii populations. Nonetheless, speciation is a continuum. Theoretically, the further we stray from the starting point, the clearer and more evident should be the differences between descendant lineages, but in the first stages of speciation, there can be divisiveness among sources of evidence — i. e. genetic data versus morphological data, nuclear versus mitochondrial DNA — because changes do not accumulate uniformly and at a fixed rate. This interval of speciation is known as the “ gray zone ” (De Queiroz 2007) and could explain why we find differences regarding the Cox 1 sequences between Corsican and Sardinian D. benazzii populations but not in the ITS- 1 or in their morphology. These results point to the need for a revision of the taxonomic status of D. benazzii, based on more data ranging from an increase of the number of nuclear markers and the use of molecular methods for species delimitation to a morphological and karyological revision of the individuals. A similar situation has been resolved in a close relative, D. subtentaculata, by the concurrent use of all these lines of evidence in an integrative way, resulting in the description of three new species that are morphologically cryptic with D. subtentaculata (Leria et al. 2020).	en	Dols-Serrate, Daniel, Leria, Laia, Aguilar, Juan Pablo, Stocchino, Giacinta Angela, Riutort, Marta (2020): Dugesia hepta and Dugesia benazzii (Platyhelminthes: Tricladida): two sympatric species with occasional sex? Organisms Diversity & Evolution (New York, N. Y.) 20 (3): 369-386, DOI: 10.1007/s13127-020-00438-z, URL: http://dx.doi.org/10.1007/s13127-020-00438-z
