Phylogenetic relationships inKerkiaand introgression betweenHauffeniaandKerkia(Caenogastropoda: Hydrobiidae)

Abstract

Freshwater truncatelloidean gastropods include numerous minute cryptic species, displaying simple morphologies, all of which hampers their taxonomic research based on morphology. Phylogenetic relationships among all but one extant species of the genus Kerkia from five localities in Croatia and one in Slovenia were therefore analysed based on one mitochondrial (cytochrome c oxidase subunit I) and three nuclear markers (18S, 28S and H3). Kerkia kusceri (Bole, ), K. jadertina Kuščer, 1933, K. j. sinjana (Kuščer, 1933), and K. kareli Beran, Bodon et Cianfanelli, 2014, were collected from their type localities. Our analysis confirmed their distinctness, recovering two additional clades that may represent yet undescribed species from Croatia. Apart from Kerkia, Hauffenia media Bole, , H. subpiscinalis (Kuščer, 1932) and H. erythropomatia (Hauffen, 1856) from Slovenia were analysed. Their distinctness together with the rejection of the eligibility for separate genus Erythropomatiana for the latter species was proven. Interestingly, its sequence divergence exceeded all previous estimates for species‐level divergence within the Truncatelloidea, implying a species‐level separation both for the COI and for nuclear loci. High p‐distances for the COI/nuclear loci (0.128/0.027, respectively) confirmed also the uniqueness of both genera. A comparison of their COI sequences with the reference sequences of Alzoniella Giusti et Bodon, 1984, Avenionia Nicolas, 1882, Fissuria Boeters, 1981, and Agrafia Szarowska et Falniowski, 2011, has shown that Kerkia and Hauffenia are not sister clades. The most striking, however, was the apparent introgression of the ‘Hauffenia’ mtDNA type from central Slovenia (cave Babja luknja) into two Kerkia clades from central (Ljubač) and southern (Podgrađe) Croatia, that are located 210 km and 360 km away, respectively. The introduced ‘Hauffenia’ mtDNA type and the closest Hauffenia erythropomatia COI differed by 0.8%. Secondary loss of isolating mechanisms between phylogenetically distant organisms and the severe lack of information on distribution of these underground taxa were postulated as possible explanations of this interesting phenomenon.

A new species of Kerkia Radoman, 1978 (Caenogastropoda, Hydrobiidae) from Bosnia and Herzegovina

“…They provided descriptions and illustrations of the shells, protoconchs, radulae, and soft part morphology and anatomy as well for all the three Croatian taxa. Rysiewska et al (2017) demonstrated molecular distinctness of those species of Kerkia.…”

First record of stygobiotic gastropod genus Travunijana Grego & Glöer, 2019 (Mollusca, Hydrobiidae) from Montenegro

“…For the Trebišnjica Basin and the northward areas, the following stygobiotic and crenobiotic genera are typical, viz. Mytilopsis Conrad, 1958;Travunijana Grego & Glöer, 2019;Emmericia Brusina, 1870;Belgrandia Bourguignat, 1869;Hadziella Kuščer, 1932;Kerkia Radoman, 1978;Narentiana Radoman, 1973;Belgrandiella A. J. Wagner, 1928;Dalmatinella Radoman, 1973;Sadleriana Clessin, 1890;Tanousia Servain, 1881 and an undescribed genus represented by "Pseudamnicola" troglobia Bole 1961 (Kuščer 1933, Schütt 2000Bilandžija et al 2013;Beran et al 2014Beran et al , 2016Rysiewska et al 2017;Hirschfelder 2018, Falniowski et al 2021. The above listed genera cannot be found in the Skadar Lake Basin (the Drin River system) and its associated Kotor Bay drainage basin, which have their typical freshwater malacofauna consisting of gastropod genera such as: Bracenica Radoman, 1973;Anagastina Radoman 1978;Stygobium Grego & Glöer, 2019;Karucia Glöer & Pešić, 2013;andZeteana Glöer &Pešić, 2014 (Reischütz andReischütz 2008;Glöer 2012, 2013a, b;Reischütz et al 2013Reischütz et al , 2014Reischütz et al , 2016Glöer and Pešić 2014a, b;Grego et al 2017.…”

Revealing the stygobiotic and crenobiotic molluscan biodiversity hotspot in Caucasus: Part I. The phylogeny of stygobiotic Sadlerianinae Szarowska, 2006 (Mollusca, Gastropoda, Hydrobiidae) from Georgia with descriptions of five new genera and twenty-one new species

“…Chertoprud et al (2016) summarised the species detected during their research in the southeast Caucasus. Nevertheless, it was clear from the above works and from recent studies of the Balkan fauna (Szarowska 2006;Beran et al 2015Beran et al , 2016Rysiewska et al 2017;Grego et al 2018;Hofman et al 2018;Osikowski et al 2018;Grego et al 2019), that the Caucasian species were assigned to respective Balkan genera (Belgrandiella, Paladilhiopsis, Plagigeyeria) based only on the few morphological features of the shell, and it is not likely that they are closely related to the geographically distant morphotypes. Molecular investigations of genus Belgrandiella from Georgia (Grego et al 2017) revealed its close relationship to the genus Agrafia Szarowska & Falniowski, 2011 from Greece.…”