Dinarippiger gen. nov. (Tettigoniidae: Bradyporinae: Ephippigerini), a new saddle bush-cricket genus for Ephippiger discoidalis Fieber, 1853 from the Dinaric karst

A new genus of the tribe Ephippigerini, Dinarippiger Skejo, Kasalo, Fontana et Tvrtković gen. nov., is described based on the characters of occiput coloration, tegmina coloration, cerci and pronotum shape. The new genus is morphologically intermediate between the genera Ephippiger Berthold, 1827 and Uromenus Bolívar, 1878, and presently includes only Dalmatian Saddle Bush Cricket, Dinarippiger discoidalis (Fieber, 1853) comb. nov., hitherto known as Ephippiger discoidalis Fieber, 1853. The species inhabits NE Italy (mainly Carso Triestino), SW Slovenia, Croatia, Bosnia & Herzegovina, and Montenegro, i.e., islands and karst habitats along the eastern Adriatic coast, with isolated findings in Albania and Italy. Its prominent variation in size and coloration has already produced many synonyms (= limbata Fischer, 1853, = limbata var. major Krauss, 1879, = limbata var. minor Krauss, 1879, = selenophora Fieber, 1853, = sphacophila Krauss, 1879), which may suggest that what is currently regarded as a single species could represent a complex of distinct species with restricted distributions. This study also presents an annotated distribution map and a bioacoustic analysis of D. discoidalis comb. nov. Further research, especially adopting molecular methods, is necessary to assess possible cryptic diversity within the genus Dinarippiger gen. nov. and elucidate its evolutionary history.

Phylogenomics of Anguis and Pseudopus (Squamata, Anguidae) indicates Balkan-Apennine mitochondrial capture associated with the Messinian event

A dated phylogenetic hypothesis on the evolutionary history of the extant taxa of the Western Palearctic lizards Anguis and Pseudopus is revised using genome-wide nuclear DNA and mitogenomes. We found overall concordance between nuclear and mitochondrial DNA phylogenies, with one significant exception - the Apennine A. veronensis. In mitochondrial DNA, this species forms a common clade with the earliest diverging lineage, the southern Balkan endemic A. cephallonica, while it clusters together with A. fragilis in nuclear DNA. The nuclear phylogeny conforms to the morphology, which is relatively similar between A. veronensis and A. fragilis. The most plausible explanation for the mitonuclear discordance is ancient mitochondrial capture from the Balkan ancestor of A. cephallonica to the Apennine population of the A. fragilis-veronensis ancestor. We hypothesize that this capture occurred only in a geographically restricted population. The dating of this presumed mitochondrial introgression and capture coincides with the Messinian event, when the Balkan and Apennine Peninsulas were presumably largely connected. The dated nuclear phylogenomic reconstruction estimated the divergence of A. cephallonica around 12 Mya, while the sister clade representing the A. fragilis species complex consisting of the sister species A. fragilis-A. veronensis and A. colchica-A. graeca further diversified around 7 Mya. The depth of nuclear divergence among the evolutionary lineages of Pseudopus (0.5-1.2 Mya) supports their subspecies status.

Phenotypic differentiation of the slow worm lizards (Squamata: Anguis) across their contact zone in Central Europe

Background

The application of molecular-phylogenetic approaches to taxonomy has had a dramatic effect on our understanding of the diversity of reptiles. These approaches have allowed researchers to reveal previously hidden lineages as well as taxonomic overestimation in morphologically plastic taxa. Slow worms, legless lizards of the genus Anguis (Squamata: Anguidae), were previously considered to comprise either one or two species, and morphology-based intraspecific taxonomy of Anguis fragilis remained controversial throughout the 20th century. After the discovery of deep genetic divergences within the genus, its taxonomy was reconsidered, and as a result, five extant species have been recognized. In order to better understand the patterns of their interspecific differentiation, here we studied phenotypic differences between the two most widespread of them—A. fragilis and A. colchica, and their putative hybrids across the contact zone of both species in Central Europe.

Methods

We used multivariate and univariate statistics and analyzed ten metric, eleven meristic, and six categorical phenotypic variables in material comprising a total of 326 individuals. We also genotyped individuals from the contact zone for one mitochondrial and two nuclear DNA fragments in order to delineate the distribution of individuals of hybrid and non-hybrid origin. The clines in morphological traits were studied using HZAR.

Results

We show that the two species are morphologically differentiated. Anguis fragilis has a less robust head, fewer scales covering the body, lower frequency of the external ear opening presence, lower frequency of separated prefrontal scales, higher frequency of prefrontal scales in contact with each other, and body coloration more similar to the juvenile coloration than A. colchica. Slow worms from the contact/hybrid zone are characterized by an intermediate morphology, with more similarities to A. fragilis than to A. colchica.

Discussion

None of the analyzed characters alone proved to be fully diagnostic, although more than 90% of all individuals could be successfully assigned to one or another species based on numbers of scales around the body. Our results indicate concordant, coincident, and steep clines in character states change. We present several hypotheses on the origin and evolutionary maintenance of the morphological divergence between both species and suggest that different evolutionary histories of the taxa rather than recently acting selection explain the observed morphological variation.

Embryonic development and perinatal skeleton in a limbless, viviparous lizard, Anguis fragilis (Squamata: Anguimorpha)

Despite the long history of embryological studies of squamates, many groups of this huge clade have received only limited attention. One such understudied group is the anguimorphs, a clade comprising morphologically and ecologically very diverse lizards. We describe several stages of embryonic development of Anguis fragilis, a limbless, viviparous anguimorph. Interestingly, in several clutches we observe high morphological variation in characters traditionally important in classifying embryos into developmental stages. The causes of this variation remain unknown but environmental factors do not seem to be very important. Additionally, we describe the state of ossification in several perinatal specimens of A. fragilis. The cranial skeleton is relatively poorly ossified around the time of birth, with all of the bones constituting the braincase unfused. On the other hand, the vertebral column is well ossified, with the neurocentral sutures closed and the neural arches fused in all postatlantal vertebrae. Such an advanced state of ossification may be related to the greater importance of the vertebral column in locomotion in limbless species than in ones with fully-developed limbs. Numerous factors seem to affect the state of ossification at the time of hatching or birth in squamates, including phylogenetic position, mode of reproduction and, potentially, limblessness. However, data from a greater number of species are needed to reach firmer conclusions about the relative importance of these variables in certain clades.

Diversity of helminths in polish reptiles: a review

The purpose of this review was to summarise the current species richness of helminths in the reptiles from Poland and to provide a host-parasite list along with studied localities. Between 1926 and 2018 the occurrence of at least 37 taxa of helminths were observed; of these, 19 belong to Trematoda, 14 to Nematoda, two to Cestoda, and two to Acanthocephala. In total, reports of 642 specimens of reptiles from 15 locations were included in this review, namely: 166 Natrix natrix (10 locations), 159 Vipera berus (6), 155 Lacerta agilis (6), 107 Zootoca vivipara (5), 52 Anguis fragilis sensu lato (4), and 3 Zamenis longissimus (1). The highest species richness of internal parasites was observed in N. natrix (at least 26 helminth taxa) and V. berus (20). Two out of nine species of reptiles, Coronella austriaca and Emys orbicularis, have not yet formed part of any helminthological surveys in Poland. To date, research conducted on helminths infecting reptiles has primarily been throughout eastern Poland. Over 60% of studied reptiles were caught in the Bieszczady Mts. or in Warsaw and its surroundings. Based on the current review, future research should focus on host species for which intestinal parasite data are poorly known i.e. E. orbicularis, Z. longissimus, C. austriaca. In general surveys should also expand into the western part of the country. Additionally, interspecies differences between two cryptic species of slow worms, Anguis fragilis and A. colchica, would provide interesting data on parasite host specificity.