Biology subjects

Fedorova, A.

Publications and source records attributed to Fedorova, A..

3 recordsLinked to original sources

bioRxiv2026

Anopheles azevedoi (Ribeiro, 1969) in Angola: New geographical records, molecular characterization, and insecticide susceptibility profile of a commonly misidentified species

BACKGROUNDAngola ranks among the five countries with the highest malaria burden globally. The Ministry of Health in Angola has consistently partnered with international donors to sustain entomological surveillance and vector control strategies in a context of high malaria burden. METHODSVector surveillance was carried out in Luanda, Benguela, Namibe and Cuanza Sul provinces from 2016-2022. Collected adult mosquitoes were tested to assess the presence of Plasmodium parasites and determine blood sources. Larvae collections provided live material to test insecticide susceptibility in local Anopheles populations. Taxonomic determination of mosquitoes was based on external morphology and confirmed with molecular assays. The presence of Anopheles azevedoi was confirmed through morphology and genetic sequences, and errors in the original species determination were detected, discussed and corrected. OBJECTIVESThe study aimed to update the geographical range of Anopheles azevedoi in Angola and monitor the species susceptibility to public health insecticides. FINDINGS and MAIN CONCLUSIONSWe report on populations of Anopheles azevedoi occurring along the western coast of Angola, a highly abundant species with anthropophilic behavior in urban areas. Anopheles azevedoi is widely resistant to pyrethroids and DDT but fully susceptible to chlorfenapyr. We contribute with COI and ITS-2 barcoding sequences for future species identification and explain the reasons for which this species has been for long misidentified in Angola.

zoology↗

bioRxiv2024

Hybridogenetic reproduction of Pelophylax water frogs from different R-E hemiclonal population systems from Eastern Ukraine: selective mortality, clonal and ploidy diversity

European water frogs from the Pelophylax esculentus complex include two sexual species, P. ridibundus and P. lessonae, and their hybrids, which usually clonally transmit one of the parental species genomes. This unique reproductive strategy allows hybrids to reproduce with one or both parental species, creating diverse population systems. Unlike most well-studied population systems in Europe, the Siverskyi Donets River basin in Eastern Ukraine features diploid and polyploid hybrids coexisting with P. ridibundus, while P. lessonae is absent (R-E systems). To reveal diverse system compositions, genetic divergence, and tadpole selective mortality, we combined novel data from over a decade of observations with previous research on population systems in the Siverskyi Donets River. Two main types of R-E systems were identified: those with diploid hybrids in northern localities and those with both diploid and triploid hybrids, extending from the mainstream of the Siverskyi Donets River to its tributaries. Additionally, we found higher genetic diversity in R-genomes compared to L-genomes, likely due to the absence of P. lessonae and the ongoing input of recombined R-genomes from P. ridibundus and triploid hybrids. This study highlights the importance of continuous monitoring and research to unravel the dynamics and complexity of water frog population systems.

zoology↗

bioRxiv2023

Formation of hemiclonal reproduction and hybridogenesis in Pelophylax water frogs studied with species-specific cytogenomic probes

Meiosis is a conservative process in all sexual organisms which ensures fertility and is central for producing genetic diversity by recombination and random segregation of parental chromosomes. Yet unexplored mechanisms may disrupt it and cause loss of sex followed by the emergence of clonal modes of reproduction. Interspecific hybridization is the primary trigger for this process, but mechanistic basis of the transition to asexuality remains still unknown for most vertebrate animals. To study these processes in water frogs, we performed reciprocal mating between two sexual species, Pelophylax ridibundus and P. lessonae, and produced vital F1 progeny (P. esculentus). The RepeatExplorer2 analysis of low-coverage genomic data of the two parental species identified the P. lessonae-specific minisatellite marker PlesSat01-48 (44 bp), which hybridized to (peri)centromeric regions of two chromosome pairs in P. lessonae - the acrocentric chromosome 8 and the chromosome 10 (a carrier of nucleolar organizer region; NOR). Chromosomal mapping combining the novel hybridization probe with the previously designed marker for P. ridibundus-specific centromeric satellite DNA showed that the P. esculentus progeny do not reproduce sexually. Instead, the F1 generation of P. esculentus instantly modified its gametogenesis and established asexual reproduction via hybridogenesis. Gametogenic modifications included premeiotic elimination of one of the parental genomes and clonal propagation of the remaining genome via endoreplication followed by standard meiotic division. The origin of DNA elimination and hybridogenesis in laboratory-produced hybrids supports a hypothesis that P. esculentus arises recurrently in nature whenever parental species come into reproductive contact. Based on the observed pattern of DNA elimination in the F1 progeny we discuss the origin and evolution of population systems in water frogs and the applicability of a newly designed chromosomal probe for other Pelophylax taxa.

evolutionary biology↗