Spiders act as one of the major predators among arthropods in agroecosystems and are crucial to the control of pest densities. As they are almost exclusively predators, they have developed a number ...of hunting strategies, which have consequently impacted their complex trophic interactions. The development of molecular biology methods for environmental DNA analysis has made it easier to analyze such complex trophic networks. In order to ascertain the trophic interactions of spiders, a sampling of spider species was carried out in two olive groves in Zadar County, Croatia, under integrated and ecological pest management. To construct the trophic networks of spiders, we performed DNA metabarcoding. The combined general and spider-excluding primers were able to recognize prey from 12 distinct orders in the guts of the 57 spiders. According to our results, spiders have a complex trophic network that exhibits seasonal and site-specific variations. The results obtained from both sites having different pest management also confirmed that spiders consumed phytophagous insects in the highest ratio, including some important pests, in comparison to other prey and that management and guild type had an impact on the predation of phytophagous insects.
The Mediterranean region has a high but unevenly studied level of invertebrate diversity. Genetic-based methods, such as DNA barcoding and metabarcoding, are proposed for biodiversity assessment; ...however, their application is not always straightforward. The current state of data available in genetic databases limits species identification, especially in the case of certain invertebrate groups. The aim of the study was (1) to assess the diversity of seven invertebrate groups, which are potential prey for predatory arthropods, in order to facilitate the analysis of the metabarcoding of trophic interactions and, thus, expand our knowledge on biocontrol potential, and (2) to estimate the representation of local species in BOLD and NCBI GenBank databases. The DNA barcoding results consisting of sequences for 269 specimens, collected in Zadar County, within Mediterranean part of Croatia, were used for species identification and species richness assessment through the comparison of our data with the data available in BOLD and NCBI databases, and by applying species delimitation methods. Previous barcode records enabled Lepidopteran, Hemipteran, Dipteran, and Hymenopteran species identification, while Collembolan and Oligochaetes species numbers were assessed using species delimitation. Our results showed that a high number of species were unique to the study area, especially in the case of Collembolans and Oligochaetes. We confirmed that the studied area is under-researched, which was particularly evident in taxonomically demanding groups, such as Collembolans and Oligochaetes, which are rich in rare endemic species.
Orthohantaviruses are mainly carried and transmitted by wild rodents, although during the last decade, they have also been identified in multiple species of shrews and moles. Orthohantavirus,
(Seewis ...virus, SWSV), first detected in Switzerland in a single
(Eurasian common shrew) specimen, has been further described in several European countries, including Croatia's neighboring Slovenia and Hungary. Croatia is a well-known endemic region for several zoonotic agents including three different orthohantaviruses:
(PUUV),
(DOBV), and
(TULV). In this study, nine shrews were tested and SWSV RNA was detected in liver, lung, and kidney belonging to two shrews (22.22%), one collected on Medvednica mountain in Zagreb County, and the other in the Stara Gradiška area in lowland Croatia. The phylogenetic analysis of the complete S segment's open reading frame (ORF) and partial L-segment revealed that the Croatian sequences, when compared to sequences from the adjacent geographic regions, form a specific genetic lineage. Two SWSV-positive shrew species-
and
(Mediterranean water shrew)-were identified using barcode-based sequence analysis. Therefore, the SWSV detection in
throughout the course of this study is seen as a rare find in this shrew species. To our knowledge, this is the first molecular and phylogenetic analysis of SWSV in Croatia.
Croatian ichthyofauna is one of the most diverse and rich in freshwater and endemic fish species in the European continent. However, to date, the distribution and phylogenetic relationships of ...certain freshwater fish species in Croatia is still not well known. In this study, we present a phylogenetic analysis of the North Italian roach (
Leucos aula
, Bonaparte, 1841) belonging to Croatian and Italian populations using nucleotide sequences of mitochondrial genes for cytochrome oxidase subunit I (
COI
mtDNA). The results confirmed the occurrence of
L. aula
on Pag Island and showed its close phylogenetic relationship with Coratian populations of the species from Ravni kotari (Baštica and Jaruga streams, Zadar County), Pazinčica River (Istria), and Zrmanja River, and with samples from three different locations in Italy (Po, Arno, and Sardinia rivers). Our study contributed to a precise understanding of the distribution of
L. aula
in the Zadar County (Croatia) and confirmed the conspecificity of Croatian and Italian populations.
The Mediterranean is characterised by high biodiversity and numerous endemic species. These species are not only present in natural habitats, but also inhabit areas under human influence, such as ...agricultural lands. In the biodiversity assessment of Mediterranean vineyards and olive orchards within Zadar County, in Croatia, we identified eight endemic species with Mediterranean distribution, six with a Balkan Peninsula distribution, four with Dinaric Alps distribution and three species rare and endangered in Europe. Alongside these species, we have recorded five new species for Croatian fauna, many of those identified by combining morphological characteristics and the DNA barcoding tool. Araneae and Coleoptera contributed the highest number of endemic species and groups with new record were the following: Coleoptera, Diptera and Araneae. Compared to other sites, an olive orchard with ecological pest management (EPM), surrounded by natural ecosystems, had the highest ratio of endemic and rare species. Our findings emphasise that agricultural lands in the Mediterranean can be habitats for endemic and rare species and that future biodiversity research of these habitats is highly important, to monitor potential biodiversity changes and motivate future species and ecosystem conservation.
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