In the Croatian fauna, horseflies (Tabanidae) are represented by 78 species belonging to two subfamilies, five tribes, and 10 genera. Identification of these species is based on morphological ...characteristics. In this study, 43 species of horseflies were analyzed. The highest number of species (19) belongs to the genus
, followed by the genera
with seven species,
with six species,
with four species,
and
with two species each, and the genera
,
, and
with one species each. The standard DNA barcoding region of the mitochondrial cytochrome c oxidase gene, subunit I (COI), was sequenced and compared to the Barcode of Life Database (BOLD). Our analyses confirmed our morphological identifications and added 16 new Barcode Index Numbers (BINs) for Tabanidae to BOLD. Potential problems in the systematics and taxonomy of this family are highlighted.
Although freshwater habitats, especially springs, are widely recognized as top-priority habitats for monitoring and conservation procedures, their fauna, especially water beetles, are still poorly ...studied in the southeastern part of Europe. Thus, the dominant water beetle in these habitats, E. bosnica (Zaitzev, 1908) (Insecta: Coleoptera: Elmidae), has been completely ignored and misidentified. This study represents the first review of its taxonomy and its population and ecological traits. Both published and unpublished data are presented and discussed, as well as the results of field sampling in 46 springs and other waterbodies conducted in this region from 2004 to 2019. The identification characters of the male genitalia and the first DNA barcode of the species are presented. The results confirm the close phylogenetic relationship of E. bosnica with E. aenea (Müller, 1806) and E. rioloides (Kuwert, 1890). The species proved to be a useful environmental descriptor and can easily be used as a biological indicator due to its easy identification. The species shows remarkable sensitivity to environmental conditions and inhabits sites that are potentially under increased anthropogenic pressure and could disappear at an alarming rate. Thus, karstic habitats should be included in future conservation and monitoring procedures in this part of Europe.
A very common intertidal alga, Corallina officinalis, serves as a refuge for numerous invertebrates within its settlements. The composition and structure of invertebrates may differ in relation to ...different natural or human-induced stress, and this study examined the effects of anthropogenic impact on the abundance and diversity of mollusks residing within C. officinalis settlements. Sampling was conducted during two seasons (Season 1 = algae’s maximum vegetation growth and Season 2 = algae’s minimum vegetation growth). Gastropods and bivalves made up 50% of all invertebrates identified, with a total of 47 species of gastropods, 25 species of bivalves, and one polyplacophoran species recorded. Considering the overall count of individuals, 4562 gastropods, 21,738 bivalves, and 260 polyplacophorans were collected from all available Corallina samples. The results indicated that locations under human impact showed a reduced number of the most abundant gastropod and bivalve species and a reduced average number of individuals.
Available research on invertebrates in Corallina officinalis settlements shows a high level of biodiversity due to a complex habitat structure. Our aim was to examine seasonal changes in the ...invertebrate population, considering the algae’s growth patterns. Nine locations with over 90% algal coverage were selected in southern Istria, where quantitative sampling was performed using six replicates of 5 × 5 cm quadrats in each location. Results showed that 29,711 invertebrates were found during winter (maximum algae growth) and 22,292 during summer (minimum algae growth), with an extrapolated average density of 220,000 and 165,200 individuals per square meter, respectively. The total number of individuals showed a linear increase as the algae biomass increased. The highest density, 586,000 individuals, was recorded in the Premantura area during winter. Dominant groups such as amphipods, polychaetes, bivalves and gastropods made up over 80% of the invertebrates. Our study confirms high invertebrate richness in the C. officinalis settlements, with the maximum density being the highest when compared to previously published data.
Molecular data for 19 specimens of Elmis syriaca syriaca and E. s. zoufali from eight countries have been analysed in order to investigate the taxonomic status and the geographical distribution of ...these two subspecies. The nominative subspecies was previously thought to be endemic to the Levant (Israel, Lebanon, Syria), while E. s. zoufali was regarded as being widespread from the Balkans to eastern Anatolia and Afghanistan. The results of our molecular studies using DNA barcoding and nuclear DNA data reveal that the two taxa are in fact distinct species, which separated around 2 Mya. A distinction based on the external morphological characters of 354 specimens was found to be impossible due to the pronounced variability, especially of the pronotal microsculpture, which had hitherto been used as the main distinguishing feature. The two species can only be distinguished by the aedeagal parameres and by the geographical distribution, which deviates considerably from the concept of previous authors. Elmis zoufali is distributed in Romania, the Balkan Peninsula, some Aegean Islands and in western Anatolia, while E. syriaca occurs from the Caucasus region southwards to eastern Turkey, Iran (probably also Afghanistan) and the Levant. Geographically, both species are widely separated by the so-called Anatolian Diagonal. Elmis zoufali resp. E. syriaca are recorded for the first time from Croatia, Romania, Azerbaijan, Georgia, Iran and Turkey. In addition, we examined 13 specimens tentatively identified as Elmis quadricollis (Reitter, 1887), a closely related species from Central Asia; we sequenced one specimen from China, which was revealed to be a sister to E. zoufali and E. syriaca.
Abstract
Major human alpha satellite DNA repeats are preferentially assembled within (peri)centromeric regions but are also dispersed within euchromatin in the form of clustered or short single ...repeat arrays. To study the evolutionary history of single euchromatic human alpha satellite repeats (ARs), we analyzed their orthologous loci across the primate genomes. The continuous insertion of euchromatic ARs throughout the evolutionary history of primates starting with the ancestors of Simiformes (45–60 Ma) and continuing up to the ancestors of Homo is revealed. Once inserted, the euchromatic ARs were stably transmitted to the descendant species, some exhibiting copy number variation, whereas their sequence divergence followed the species phylogeny. Many euchromatic ARs have sequence characteristics of (peri)centromeric alpha repeats suggesting heterochromatin as a source of dispersed euchromatic ARs. The majority of euchromatic ARs are inserted in the vicinity of other repetitive elements such as L1, Alu, and ERV or are embedded within them. Irrespective of the insertion context, each AR insertion seems to be unique and once inserted, ARs do not seem to be subsequently spread to new genomic locations. In spite of association with (retro)transposable elements, there is no indication that such elements play a role in ARs proliferation. The presence of short duplications at most of ARs insertion sites suggests site-directed recombination between homologous motifs in ARs and in the target genomic sequence, probably mediated by extrachromosomal circular DNA, as a mechanism of spreading within euchromatin.
The Balkan Peninsula is a hot spot for European herpetofaunal biodiversity and endemism. The rock climbing lizards Dalmatolacerta oxycephala and Dinarolacerta mosorensis and the ground‐dwelling ...Dalmatian wall lizard Podarcis melisellensis are endemic to the Western Balkans, and their ranges largely overlap. Here, we present a comparative phylogeographical study of these three species in the area of their codistribution in order to determine the level of concordance in their evolutionary patterns. Phylogenetic analyses were performed based on two mitochondrial genes (cytochrome b and 16S rRNA), and a molecular clock approach was used to date the most important events in their evolutionary histories. We also tested for correlations regarding genetic differentiation among populations and their geographical distances. For all three species, a significant correlation between genetic and geographical distances was found. Within D. oxycephala, two deeply separated clades (‘island’ and ‘mainland clade’), with further subdivision of the ‘mainland clade’ into two subclades (‘south‐eastern’ and ‘north‐western’), were found. High sequence divergences were observed between these groups. From our data, the time of separation of the two main clades of D. oxycephala can be estimated at about 5 mya and at about 0.8 mya for the two subclades of the mainland clade. Within D. mosorensis, coalescence time may be dated at about 1 mya, while D. mosorensis and D. montenegrina separated around 5 mya. The results imply the existence of complex palaeo‐biogeographical and geological factors that probably influenced the observed phylogeographical patterns in these lacertid species, and point to the presence of numerous glacial/interglacial refugia. Furthermore, the observed cryptic genetic diversity within the presently monotypic species D. oxycephala prompts for a revision of its taxonomic and conservation status.
Global climate change and the accompanying rise in temperature could affect the biology and ecology of a number of vectors, including mosquitoes. High altitude areas that were previously unsuitable ...for the spread of mosquito vector populations could become suitable. The aim of this research was to study the distribution of mosquito species in higher altitude regions of Croatia. Samples were collected in three areas: Slavonian Mountains, Gorski Kotar, and Middle Velebit. Specimens were morphologically determined and confirmed by DNA barcoding and other genetic markers and showed the presence of 16 species belonging to six genera. The most abundant species were the Culex pipiens complex with 50% of the collected specimens. Both pipiens (Linnaeus, 1758) and molestus (Forskal, 1775) biotypes and their hybrids were identified within the complex, followed by Culex torrentium (Martini, 1925) (20.2%), Culiseta longiareolata (Macquart, 1838) (8.5%), and the invasive species Aedes japonicus (Theobald, 1901) (7.8% of the total number of collected specimens). The remaining 12 species made up 14.7% of the collected specimens. Intraspecific COI p-distances were within the standard barcoding threshold for OTUs, while interspecific genetic distances were much higher, confirming the existence of barcoding gaps. Mosquito fauna of Croatian mountains showed a moderate variety and made 30.8% of the total number of recorded mosquito species in Croatia thus far.
Satellite DNAs are tandemly repeated sequences clustered within heterochromatin. However, in some cases, such as the major TCAST1 satellite DNA from the beetle
, they are found partially dispersed ...within euchromatin. Such organization together with transcriptional activity enables TCAST1 to modulate the activity of neighboring genes. In order to explore if other
repetitive families have features that could provide them with a possible gene-modulatory role, we compare here the structure, organization, dispersion profiles, and transcription activity of 10 distinct TCAST repetitive families including TCAST1. The genome organization of TCAST families exhibit either satellite-like or transposon-like characteristics. In addition to heterochromatin localization, bioinformatic searches of the assembled genome have revealed dispersion of all families within euchromatin, preferentially in the form of single repeats. Dispersed TCAST repeats are mutually correlated in distribution and are grouped in distinct regions of euchromatin. The repeats are associated with genes, are enriched in introns relative to intergenic regions, and very rarely overlap exons. In spite of the different mechanisms of repeat proliferation, such as transposition and homologous recombination, all TCAST families share a similar frequency of spreading as well as dispersion and gene association profiles. Additionally, TCAST families are transcribed and their transcription is significantly activated by heat stress. A possibility that such common features of TCAST families might be related to their potential gene-modulatory role is discussed.
The complete mitochondrial DNA (mtDNA) genome of the
Eunapius subterraneu
s (Porifera, Demospongiae), a unique stygobitic sponge, was analyzed and compared with previously published mitochondrial ...genomes from this group. The 24,850 bp long mtDNA genome is circular with the same gene composition as found in other metazoans. Intergenic regions (IGRs) comprise 24.7% of mtDNA and are abundant with direct and inverted repeats and palindromic elements as well as with open reading fames (ORFs) whose distribution and homology was compared with other available mt genomes with a special focus on freshwater sponges. Phylogenetic analyses based on concatenated amino acid sequences from 12 mt protein genes placed
E.
subterraneus
in a well-supported monophyletic clade with the freshwater sponges,
Ephydatia muelleri
and
Lubomirskia baicalensis
. Our study showed high homology of mtDNA genomes among freshwater sponges, implying their recent split.
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