Cryptic diversity within endemic Italian barbels: revalidation and description of new Barbus species (Teleostei: Cyprinidae)

Abstract

Two fluviolacustrine lineages (SI1 Barbus and SI2 Barbus) of the Barbus genus have been recently detected in the Apulia-Campania ichthyogeographic district (southern Italy). The aim of this study was to determine the taxonomic status of these lineages by comparing them with the two already-established Italian fluviolacustrine species Barbus plebejus and Barbus tyberinus through a more in-depth molecular and morphological investigation. Genetic analyses were performed on both mitochondrial (cytochrome b) and nuclear (growth hormone paralog 2) DNA markers, and morphological analyses were carried out on specific age classes and purebred populations. Molecular analyses detected four evolutionary lineages at the mitochondrial level, whereas the nuclear data set highlighted the strict evolutionary relation between B. plebejus sensu stricto and the new lineages, converged in the B. plebejus complex clade. The morphological analyses allowed us to discriminate SI1 Barbus and SI2 Barbus from both B. plebejus and B. tyberinus. The new taxa could be discriminated by the greatest maximum body height and the longest pre-orbital distance, respectively. Both the new lineages have longer ventral and pectoral fins than B. plebejus and B. tyberinus, a larger caudal fin than B. tyberinus and a lower number of scales along the lateral line than B. plebejus. Both molecular and morphological results suggested the two southern Italian lineages could be considered as distinct endemic species: the formal description of the new species Barbus samniticus sp. nov. (i.e., SI1 Barbus) and the revalidation of Barbus fucini Costa, 1853 (i.e., SI2 Barbus) were thus proposed, and, for both species, molecular and morphological diagnosis were provided.

New data on the distribution of the Volturno spined loach Cobitis zanandreai (Teleostei: Cobitidae )

“…The range of C. zanandreai falls into the area that has been proposed as the Apulo-Campanian ichthyo-geographical district (Bianco, 2014;Ketmaier et al, 2009) which is characterized by the presence of other endemic fishes: Barbus fucini, a species of barbel recently revalidated by Lorenzoni et al (2021), Alburnus albidus, and the southern clade of Telestes muticellus (Buj et al, 2017), considered as a separate species by Bianco (2014). Considering the articulated tectonic setting established in the earliest Pliocene (Cardello et al, 2021) of faulting and volcanic eruptions, such as the emergence of the Roccamonfina volcano about 650,000 years BP (Radicati di Brozolo et al, 1988;Rouchon et al, 2008) and the disappearance of the Lirino Lake about 346,000 years BP (Devoto, 1965;Marra et al, 2021).…”

Phylogeography of Aphanius fasciatus (Osteichthyes: Aphaniidae) in the Mediterranean Sea, with a focus on its conservation in Cyprus

“…A break between the Aegean Sea (including any population in the Black Sea) and the remaining Mediterranean Sea has been identified in some demersal species (Suzuki et al, 2004;Domingues et al, 2005), but in these cases the degree of genetic divergence is much lower than that identified between A. fasciatus and A. almiriensis, suggesting a less pronounced effect of the Southern Aegean as a phylogeographical barrier. Conversely, although A. fasciatus might thrive in internal water bodies, its ability to inhabit coastal environments and to occasionally use marine environments for dispersal (Torchio, 1967;Ç oker & Akyol, 2014) makes its phylogeographical pattern completely different from those identified in exclusive freshwater species, that are often restricted to a single river drainage (Perea & Doadrio, 2015;Lorenzoni et al, 2021), and usually show the occurrence of several inland glacial refugia (Costedoat & Gilles, 2009). A comparison with fish species typically associated to brackish-water environments, and with an apparently similar ecology, provides more suitable comparisons.…”

Phylogeography of Sarmarutilus rubilio (Cypriniformes: Leuciscidae): Complex Genetic Structure, Clues to a New Cryptic Species and Further Insights into Roaches Phylogeny

“…Despite this, the current distribution of Sarmarutilus haplogroups only partially matches the currently recognized ichthyogeographic Italian districts, which are characterized by different hydrogeological histories and evolution and are inhabited by different species [ 21 , 97 ]. See details on each haplogroup below.…”