Intraspecific Genetic Variation Research Articles

Intraspecific genetic variation in host vigour, viral load and disease tolerance during Drosophila C virus infection.

Genetic variation for resistance and disease tolerance has been described in a range of species. In Drosophila melanogaster, genetic variation in mortality following systemic Drosophila C virus (DCV) infection is driven by large-effect polymorphisms in the restriction factor pastrel (pst). However, it is unclear if pst contributes to disease tolerance. We investigated systemic DCV challenges spanning nine orders of magnitude, in males and females of 10 Drosophila Genetic Reference Panel lines carrying either a susceptible (S) or resistant (R) pst allele. We find among-line variation in fly survival, viral load and disease tolerance measured both as the ability to maintain survival (mortality tolerance) and reproduction (fecundity tolerance). We further uncover novel effects of pst on host vigour, as flies carrying the R allele exhibited higher survival and fecundity even in the absence of infection. Finally, we found significant genetic variation in the expression of the JAK-STAT ligand upd3 and the epigenetic regulator of JAK-STAT G9a. However, while G9a has been previously shown to mediate tolerance of DCV infection, we found no correlation between the expression of either upd3 or G9a on fly tolerance or resistance. Our work highlights the importance of both resistance and tolerance in viral defence.

Historic and contemporary biogeographic perspectives on range-wide spatial genetic structure in a widespread seagrass.

Historical and contemporary processes drive spatial patterns of genetic diversity. These include climate-driven range shifts and gene flow mediated by biogeographical influences on dispersal. Assessments that integrate these drivers are uncommon, but critical for testing biogeographic hypotheses. Here, we characterize intraspecific genetic diversity and spatial structure across the entire distribution of a temperate seagrass to test marine biogeographic concepts for southern Australia. Predictive modeling was used to contrast the current Posidonia australis distribution to its historical distribution during the Last Glacial Maximum (LGM). Spatial genetic structure was estimated for 44 sampled meadows from across the geographical range of the species using nine microsatellite loci. Historical and contemporary distributions were similar, with the exception of the Bass Strait. Genetic clustering was consistent with the three currently recognized biogeographic provinces and largely consistent with the finer-scale IMCRA bioregions. Discrepancies were found within the Flindersian province and southwest IMCRA bioregion, while two regions of admixture coincided with transitional IMCRA bioregions. Clonal diversity was highly variable but positively associated with latitude. Genetic differentiation among meadows was significantly associated with oceanographic distance. Our approach suggests how shared seascape drivers have influenced the capacity of P. australis to effectively track sea level changes associated with natural climate cycles over millennia, and in particular, the recolonization of meadows across the Continental Shelf following the LGM. Genetic structure associated with IMCRA bioregions reflects the presence of stable biogeographic barriers, such as oceanic upwellings. This study highlights the importance of biogeography to infer the role of historical drivers in shaping extant diversity and structure.

Geographic Variation in Skull Morphology of the Japanese Crocodile Newt, Echinotriton andersoni (Amphibia: Urodela: Salamandridae), Inferred from Geometric Morphometrics

The Anderson's crocodile newt, Echinotriton andersoni, is an endangered species distributed in the islands of Central Ryukyus, Japan. This species is well known to show high intraspecific genetic variation among islands, but its morphological variation has not been explored. We examined the skull variation in this species including enigmatic specimens collected from Taiwan by using geometric morphometrics, and found sexual differences and geographic variation mainly between the Okinawa group (Okinawajima Island) and the Amami Group (Amamioshima and Tokunoshima Islands). We further found close resemblance between the Taiwanese specimens and the female specimens from Amamioshima Island.

Assessing Intraspecific Genetic Variability in Cannabis sativa Populations of Punjab Pakistan Using RAPD and DNA Barcode Markers

Cannabis sativa possess substantial amount of omega-3 fatty acids and several medicinal benefits with potential secondary metabolites. This study employed rbcL, matK, and trnH-psbA barcode markers and RAPD marker to explore genetic diversity in C. sativa populations in Punjab, Pakistan. In population genetic study using DNA barcode markers, cladogram showed investigated samples were genetically similar; however, demonstrated significant genetic diversity with the available DNA sequences of this plant from other regions and countries. The nucleotide sequence variation (% divergence) indicated high intraspecific variation in plants of different geographical zones. However, the RAPD marker analysis displayed genetic diversity among collected Cannabis sativa samples. The principal component analysis reinforced these findings by providing a spatial representation of genetic distances among the samples that revealed a considerable genetic diversity among the collected material and significant intraspecific variation was observed, indicating diverse genetic profiles across geographical regions. This research highlights the potential of molecular markers in germplasm selection for breeding programs.

Genetic relationships of Arachis (Fabaceae) accessions based on microsatellite markers

The genus Arachis is endemic to South America and contains 83 described species assembled into nine taxonomical sections. The section Arachis is of particular interest because it includes the cultivated peanut (A. hypogaea) and its closely related wild species. In this study, we used 26 microsatellite markers to analyze the genetic variability and relationships of some recently collected germplasm accessions of species in the Arachis section, with emphasis on the B genome species. The knowledge of the genetic relationships among species and accessions is necessary for a more efficient management of germplasm collections and use of wild species for crop improvement. This is especially important for the B genome species, as only one accession of A. ipaënsis, the B genome donor to the allotetraploid A. hypogaea (AABB), is available in germplasm collections worldwide. The results shed more light on the genetic relationships between accessions of A. ipaënsis, A. gregoryi, A. magna, A. valida and A. williamsii, what expands the number of accessions for incorporation of useful genes from the species associated with the peanut B genome. The analyses also showed a generally high level of intraspecific genetic variability, but usually grouped the accessions according to their genome types and species. However, accessions of some species did not group as expected, and these results suggest the need of further taxonomic revision of a few taxa, especially some accessions of A. gregoryi, A. magna and A. kuhlmannii and the circumscriptions of sections Erectoides and Procumbentes.

Syntenic Cell Wall QTLs as Versatile Breeding Tools: Intraspecific Allelic Variability and Predictability of Biomass Quality Loci in Target Plant Species

Syntenic cell wall QTLs (SQTLs) can identify genetic determinants of biomass traits in understudied species based on results from model crops. However, their effective use in plant breeding requires SQTLs to display intraspecific allelic variability and to predict causative loci in other populations/species than the ones used for SQTLs identification. In this study, genome assemblies from different accessions of Arabidopsis, rapeseed, tomato, rice, Brachypodium and maize were used to evaluate the intraspecific variability of SQTLs. In parallel, a genome-wide association study (GWAS) on cell wall quality traits was performed in miscanthus to verify the colocalization between GWAS loci and miscanthus SQTLs. Finally, an analogous approach was applied on a set of switchgrass cell wall QTLs retrieved from the literature. These analyses revealed large SQTLs intraspecific genetic variability, ranging from presence-absence gene variation to SNPs/INDELs and changes in coded proteins. Cell wall genes displaying gene dosage regulation, such as PAL and CAD, displayed presence-absence variation in Brachypodium and rapeseed, while protein INDELs were detected for the Brachypodium homologs of the rice brittle culm-like 8 locus, which may likely impact cell wall quality. Furthermore, SQTLs significantly colocalized with the miscanthus and switchgrass QTLs, with relevant cell wall genes being retained in colocalizing regions. Overall, SQTLs are useful tools to screen germplasm for relevant genes and alleles to improve biomass quality and can increase the efficiency of plant breeding in understudied biomass crops.

Pan-Plastome of Greater Yam (Dioscorea alata) in China: Intraspecific Genetic Variation, Comparative Genomics, and Phylogenetic Analyses

Dioscorea alata L. (Dioscoreaceae), commonly known as greater yam, water yam, or winged yam, is a popular tuber vegetable/food crop worldwide, with nutritional, health, and economical importance. China is an important domestication center of D. alata, and hundreds of cultivars (accessions) have been established. However, genetic variations among Chinese accessions remain ambiguous, and genomic resources currently available for the molecular breeding of this species in China are very scarce. In this study, we generated the first pan-plastome of D. alata, based on 44 Chinese accessions and 8 African accessions, and investigated the genetic variations, plastome evolution, and phylogenetic relationships within D. alata and among members of the section Enantiophyllum. The D. alata pan-plastome encoded 113 unique genes and ranged in size from 153,114 to 153,161 bp. A total of four whole-plastome haplotypes (Haps I-IV) were identified in the Chinese accessions, showing no geographical differentiation, while all eight African accessions shared the same whole-plastome haplotype (Hap I). Comparative genomic analyses revealed that all four whole plastome haplotypes harbored identical GC content, gene content, gene order, and IR/SC boundary structures, which were also highly congruent with other species of Enantiophyllum. In addition, four highly divergent regions, i.e., trnC-petN, trnL-rpl32, ndhD-ccsA, and exon 3 of clpP, were identified as potential DNA barcodes. Phylogenetic analyses clearly separated all the D. alata accessions into four distinct clades corresponding to the four haplotypes, and strongly supported that D. alata was more closely related to D. brevipetiolata and D. glabra than D. cirrhosa, D. japonica, and D. polystachya. Overall, these results not only revealed the genetic variations among Chinese D. alata accessions, but also provided the necessary groundwork for molecular-assisted breeding and industrial utilization of this species.

Spatio-temporal genetic structure of the striped field mouse (Apodemus agrarius) populations inhabiting national parks in South Korea: Implications for conservation and management of protected areas

Population or habitat connectivity is a key component in maintaining species and community-level regional biodiversity as well as intraspecific genetic diversity. Ongoing human activities cause habitat destruction and fragmentation, which exacerbate the connectivity due to restricted animal movements across local habitats, eventually resulting in the loss of biodiversity. The Baekdudaegan Mountain Range (BMR) on the Korean Peninsula represents “biodiversity hotspots” and eight of the 22 Korean national parks are located within the BMR. Given the striped field mouse (Apodemus agrarius) is the most common and ecologically important small mammals in these protected areas, the population genetic assessment of this species will allow for identifying “genetic diversity hotspots” and also “genetic barriers” that may hinder gene flow, and will therefore inform on effective conservation and management efforts for the national park habitats. We collected samples from hair, tail, or buccal swabs for 252A. agrariusindividuals in 2015 and 2019. By using mitochondrial DNA cytochromeb(cyt b) sequences and nine microsatellite loci, we determined levels of genetic diversity, genetic differentiation, and gene flow among eight national park populations ofA. agrariusalong the BMR. We found high levels of genetic diversity but the occurrences of inbreeding for all the nine samples analyzed. Our results also indicated that there was detectable temporal genetic variation between the 2015 and 2019 populations in the Jirisan National Park, which is probably due to a short-term decline in genetic diversity caused by reduced population sizes. We also found a well-admixed shared gene pool among the national park populations. However, a significant positive correlation between geographic and genetic distances was detected only in mtDNA but not microsatellites, which might be attributed to different dispersal patterns between sexes. There was a genetic barrier to animal movements around the Woraksan National Park areas. The poor habitat connectivity surrounding these areas can be improved by establishing an ecological corridor. Our findings of the presence of genetic barriers in some protected areas provide insights into the conservation and management efforts to improve the population or habitat connectivity among the national parks.

Genetic analysis reveals conspecificity of two nominal species of Anaphes fairyflies (Hymenoptera: Mymaridae), egg parasitoids of Oulema leaf beetle (Coleoptera: Chrysomelidae) pests of cereal crops in Europe and of rice in East Asia.

Anaphes (Anaphes) flavipes (Foerster), a fairyfly (Hymenoptera: Mymaridae) native of Europe, is an economically important egg parasitoid for the natural control of Oulema spp. leaf beetle (Coleoptera: Chrysomelidae) pests of cereal crops such as barley, oats, rye, and wheat in Europe, and for the classical biological control of the invasive Oulema melanopus (L.) in North America. A morphologically very similar Anaphes (Anaphes) nipponicus Kuwayama, known from mainland China, Japan, Republic of Korea, Far East of Russia and Taiwan, is an egg parasitoid of Oulema oryzae (Kuwayama), a pest of rice mainly in temperate parts of East Asia. The nuclear 28S-D2 and ITS2 and the mitochondrial COI genes were used as markers to compare specimens of A. (Anaphes) flavipes reared from eggs of an Oulema sp. on barley in Germany with those of A. (Anaphes) nipponicus reared from eggs of O. oryzae on rice in Honshu Island, Japan. Because the resulting sequences are practically identical, within an expected intraspecific genetic variability, conspecificity of these two nominal species has been confirmed, and consequently A. (Anaphes) nipponicus Kuwayama, 1932, syn. n. is synonymized with A. (Anaphes) flavipes (Foerster, 1841). Taxonomic notes and illustrations are provided for the specimens of both sexes of A. (Anaphes) flavipes from Japan to facilitate their recognition.

Evolution in the dark: Unexpected genetic diversity and morphological stasis in the blind, aquifer-dwelling catfish Horaglanis

The lateritic aquifers of the southern Indian state of Kerala harbour a unique assemblage of enigmatic stygobitic fishes which are encountered very rarely, only when they surface during the digging and cleaning of homestead wells. Here, we focus on one of the most unusual members of this group, the catfish Horaglanis, a genus of rarely-collected, tiny, blind, pigment less, and strictly aquifer-residing species. A six-year exploratory and citizen-science backed survey supported by molecular phylogenetic analysis reveals novel insights into the diversity, distribution and population structure of Horaglanis. The genus is characterized by high levels of intraspecific and interspecific genetic divergence, with phylogenetically distinct species recovered above a 7.0% genetic-distance threshold in the mitochondrial cytochrome oxidase subunit 1 gene. Contrasting with this deep genetic divergence, however, is a remarkable stasis in external morphology. We identify and describe a new cryptic species, Horaglanis populi, a lineage that is the sister group of all currently known species. All four species are represented by multiple haplotypes. Mismatch distribution reveals that populations have not experienced recent expansions.

The InBIO barcoding initiative database: DNA barcodes of Iberian Trichoptera, documenting biodiversity for freshwater biomonitoring in a Mediterranean hotspot.

The Trichoptera are an important component of freshwater ecosystems. In the Iberian Peninsula, 380 taxa of caddisflies are known, with nearly 1/3 of the total species being endemic in the region. A reference collection of morphologically identified Trichoptera specimens, representing 142 Iberian taxa, was constructed. The InBIO Barcoding Initiative (IBI) Trichoptera 01 dataset contains records of 438 sequenced specimens. The species of this dataset correspond to about 37% of Iberian Trichoptera species diversity. Specimens were collected between 1975 and 2018 and are deposited in the IBI collection at the CIBIO (Research Center in Biodiversity and Genetic Resources, Portugal) or in the collection Marcos A. González at the University of Santiago de Compostela (Spain). Twenty-nine species, from nine different families, were new additions to the Barcode of Life Data System (BOLD). A success identification rate of over 80% was achieved when comparing morphological identifications and DNA barcodes for the species analysed. This encouraging step advances incorporation of informed Environmental DNA tools in biomonitoring schemes, given the shortcomings of morphological identifications of larvae and adult Caddisflies in such studies. DNA barcoding was not successful in identifying species in six Trichoptera genera: Hydropsyche (Hydropsychidae), Athripsodes (Leptoceridae), Wormaldia (Philopotamidae), Polycentropus (Polycentropodidae) Rhyacophila (Rhyacophilidae) and Sericostoma (Sericostomatidae). The high levels of intraspecific genetic variability found, combined with a lack of a barcode gap and a challenging morphological identification, rendered these species as needing additional studies to resolve their taxonomy.

Predictors of genomic diversity within North American squamates.

Comparisons of intraspecific genetic diversity across species can reveal the roles of geography, ecology, and life history in shaping biodiversity. The wide availability of mitochondrial DNA (mtDNA) sequences in open-access databases makes this marker practical for conducting analyses across several species in a common framework, but patterns may not be representative of overall species diversity. Here, we gather new and existing mtDNA sequences and genome-wide nuclear data (genotyping-by-sequencing; GBS) for 30 North American squamate species sampled in the Southeastern and Southwestern United States. We estimated mtDNA nucleotide diversity for 2 mtDNA genes, COI (22 species alignments; average 16 sequences) and cytb (22 species; average 58 sequences), as well as nuclear heterozygosity and nucleotide diversity from GBS data for 118 individuals (30 species; 4 individuals and 6,820 to 44,309 loci per species). We showed that nuclear genomic diversity estimates were highly consistent across individuals for some species, while other species showed large differences depending on the locality sampled. Range size was positively correlated with both cytb diversity (phylogenetically independent contrasts: R2 = 0.31, P = 0.007) and GBS diversity (R2 = 0.21; P = 0.006), while other predictors differed across the top models for each dataset. Mitochondrial and nuclear diversity estimates were not correlated within species, although sampling differences in the data available made these datasets difficult to compare. Further study of mtDNA and nuclear diversity sampled across species' ranges is needed to evaluate the roles of geography and life history in structuring diversity across a variety of taxonomic groups.

Transposable elements are associated with genome-specific gene expression in bread wheat.

Recent studies in wheat emphasized the importance of TEs, which occupy ~85% of the wheat genome, as a major source of intraspecific genetic variation due to their recent activity and involvement in genomic rearrangements. The contribution of TEs to structural and functional variations in bread wheat genes is not fully understood. Here, publicly available RNA-Seq databases of bread wheat were integrated to identify TE insertions within gene bodies (exons\ introns) and assess the impact of TE insertions on gene expression variations of homoeologs gene groups. Overall, 70,818 homoeologs genes were analyzed: 55,170 genes appeared in each one of the three subgenomes (termed ABD), named triads; 12,640 genes appeared in two of the three subgenomes (in A and B only, termed AB; or in A and D only, termed AD; or in B and D only, termed BD);, named dyads; and 3,008 genes underwent duplication in one of the three subgenomes (two copies in: subgenome A, termed AABD; subgenome B, termed ABBD; or subgenome D, termed ABDD), named tetrads. To this end, we found that ~36% of the 70,818 genes contained at least one TE insertion within the gene body, mostly in triads. Analysis of 14,258 triads revealed that the presence of TE insertion in at least one of the triad genes (7,439 triads) was associated with balanced expression (similar expression levels) between the homoeolog genes. TE insertions within the exon or in the untranslated regions (UTRs) of one or more of the homoeologs in a triad were significantly associated with homoeolog expression bias. Furthermore, we found a statistically significant correlation between the presence\absence of TEs insertions belonging to six TE superfamilies and 17 TE subfamilies and the suppression of a single homoeolog gene. A significant association was observed between the presence of TE insertions from specific superfamilies and the expression of genes that are associated with biotic and abiotic stress responses. Our data strongly indicate that TEs might play a prominent role in controlling gene expression in a genome-specific manner in bread wheat.

Evidence of the association between the Q2 mitochondrial group of Bemisia tabaci MED species (Hemiptera: Aleyrodidae) and low competitive displacement capability.

The whitefly, Bemisia tabaci (Gennadius), is one of the most serious agricultural pests worldwide. Bemisia tabaci is a cryptic species complex of more than 40 species among which the invasive MEAM1 and MED species are the most widespread and economically important. Both MEAM1 and MED present intraspecific genetic variability and some haplotypes are reported to be more invasive than others. MED can be further deconstructed into different genetic groups, including MED-Q1 and MED-Q2. However, distinct biological phenotypes discerning the different MED mitochondrial haplotypes are yet to be characterized. Competitive displacement and life-history trials were carried out between MED-Q2 and MEAM1 populations collected in Florida, USA. In addition, a phylogenetic analysis was carried out including populations from previous whitefly competitive displacement studies for identification and comparison of the MED mitochondrial groups. In contrast to other studies with MED-Q1, the MED-Q2 population from Florida is less likely to displace MEAM1 on pepper. In addition, both pepper and watermelon were a more favorable host to MEAM1 compared to MED-Q2 according to the life history trials.

Inconsistency between morphological diversity and genetic structuring: proposal for one species of Undaria in Japan

Abstract Genetic structure analyses have yielded some examples of inconsistencies between genetic and morphological information. Here, eleven nuclear microsatellite markers and mitochondrial haplotypes were used to examine the genetic structure and gene flow among Japanese Undaria pinnatifida populations and the congeneric species U. undarioides and U. peterseniana. Undaria pinnatifida was subdivided into four “Groups” of populations based on Bayesian clustering analysis, Neighbor-net analysis and Principal coordinate analysis (PCoA). Undaria undarioides samples formed a unique Group. In contrast, U. peterseniana samples either grouped with a mixture of U. pinnatifida and U. undarioides clusters or were included within one of the U. pinnatifida clusters. More significantly, Groups of populations shared alleles with geographically adjacent Groups even between different morphospecies. No clear differences between the inter-and intra-specific genetic divergence were observed in either nuclear or mitochondrial markers. As a result, U. undarioides and U. peterseniana were synonymized with U. pinnatifida. Isolation-by-distance suggested the significance of geographical isolation for maintaining the observed divergence.

Molecular and morphological characterization of Andracantha gravida (Alegret, 1941) (Acanthocephala: Polymorphidae) in piscivorous birds from the Gulf of Mexico.

Adult specimens of Andracantha gravida (Alegret, 1941) were recorded from the intestines of the double-crested cormorant Nannopterum auritus (Lesson) (type host) and brown pelican Pelecanus occidentalis L. in two localities from Mexico: Celestún, Yucatan (south-eastern) and Punta Piedra, Tamaulipas (north-eastern). The specimens of A. gravida are morphologically characterized by having a pipe-shaped body without swellings, the absence of small trunk spines between the two fields of spines on the foretrunk and a cylindrical proboscis with 14-16 rows of 10-12 hooks per row. Newly generated partial sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were generated from adult isolates of A. gravida from Mexico and compared with one sequence of A. gravida and with sequences of other polymorphid acanthocephalans available in GenBank. Phylogenetic analyses based on maximum likelihood and Bayesian inference methods of the cox1 dataset placed all the species of Andracantha in a single clade, with weak support. The analyses of the cox1 dataset placed Andracantha sigma Presswell, García-Varela & Smales, , as sister to the clade formed by A. gravida, Andracantha phalacrocoracis (Yamaguti, 1939), Andracantha leucocarboi Presswell, García-Varela & Smales, and an unidentified species of Andracantha from Japan. The newly generated cox1 sequences of A. gravida from piscivorous birds of Mexico formed a strongly supported clade with the published sequence of A. gravida from the double-crested cormorant from the south-eastern coast of Mexico. The intraspecific genetic divergence among isolates identified as A. gravida ranged from 0.0% to 2.2%. A cox1 haplotype network inferred with 14 sequences revealed the presence of nine haplotypes, two of which were shared between the populations of piscivorous birds from the north-eastern and south-eastern coasts of Mexico and seven of which were unique. The fixation index between the populations from north-eastern and south-eastern Mexico was low (0.06949), which suggests genetic flow. This can be explained by the migration patterns of the brown pelican and the double-crested cormorant along the coasts of the Gulf of Mexico.

Diversity of helminths with zoonotic potential and molecular characterization of Toxocara canis infecting domestic dogs from locations of Amazon and Atlantic Forest Brazilian biomes.

The coproparasitological examination of dogs (n=278) from two Brazilian biomes (Amazon [AZ] and Atlantic Forest [AF]) by centrifugal flotation demonstrated positivity values of 54.2% (AF) and 48.5% (AZ). The most prevalent parasites in AF were hookworms (81.0% - 47/58), Toxocara sp. (17.3% - 10/58) and Trichuris vulpis (12.1% - 7/58); while in AZ they were hookworms (86.7% - 72/83), Toxocara sp. (18.1% - 15/83), Dipylidium caninum (13.3% - 11/83) and T. vulpis (10.8% - 9/83). PCR was performed using the partial mitochondrial genes cytochrome c oxidase subunit 1 (pcox1) and NADH dehydrogenase 1 (pnad1) in 25 fecal samples positive for Toxocara sp. eggs and found one sample positive for pcox1 and six positives for pnad1. The sequencing of these samples was unsuccessful due to the difficulties inherent in copro-PCR+sequencing. The sequencing of 14 samples of T. canis adult helminths retrieved 11 sequences of 414 bp for pcox1 and nine sequences of 358 bp for pnad1. The phylogenetic trees of these sequences confirmed the species T. canis. Intraspecific genetic variation was only observed for pnad1. This is the second study involving molecular analysis of T. canis in dogs from Brazil and adds new information through the use of pnad1.

GENETIC FEATURES OF TARPAN-LIKE HORSES OF THE POLISH PRIMITIVE (THE KONIK) BREED AND ESTABLISHMENT OF PHYLOGENETIC OF ANCIENT EGUIDS USING THE ISSR-PCR MARK

In the development of human society, the horse, compared to other domestic animals, played a central role. It became an integral part of the economic and intellectual development of ancient human settlements, a symbol of the transformation of subsequent great epochs. The last wild horse that survived in Ukraine until the end of the XIX century, according to many paleontologists, was the tarpan. However, this statement is still questioned. In the books and documents of old chroniclers and researchers we find descriptions of wild horses called tarpans, which could be found in the wooded areas of Poland, Lithuania and Prussia in the XVIII century. Emphasizing the forest existence of these horses, they received the Latin name Equii silvestris (forest horses). According to historical records, tarpans survived the longest in the wild in the vicinity of Bialowieza Forest, more or less until 1780, when they were finally caught and transferred to the Zoo of the Counts of Zamoyski (an influential Polish count) in the town of Zwierzyniec near the town of Bilhora in Lublin Voivodeship in eastern Poland. Around 1806, the zoo ceased to exist, and the horses were distributed to local peasants. Thus, we can assume that this is the last case of domestication of wild horses in Poland. The World Wide Fund for Nature (WWF) has launched a program to return the tarpan-like Polish horse to nature. Therefore, tarpan-like horses were brought to the Belarusian part of Belovezhskaya Pushcha and to the south-west of Latvia (1999) [11]. In 2009, with the consent of the Ministry of Environment of Ukraine and the Ministry of Nature Protection of Poland, horses of the descendants of the wild tarpan horse were brought to the territory of Yavoriv National Nature Park from Roztochansky National Park to preserve and reproduce the gene pool of these horses. However, the origin of the domestic horse and the history of most modern breeds remains unclear to this day. This is due to the fact that the bones of wild and domesticated horses are almost identical. The lack of diagnostic, anatomical and biometric criteria does not allow to determine the archaeozoological remains of the horse. To solve these problems molecular genetic analysis of horse DNA is used. With the use of molecular markers in research, there are new opportunities to study genetic diversity, as well as the definition of phylogenetic relationships at both intra- and interspecific levels. One of the types of genetic polymorphism research is ISSR-PCR - amplification of intermicrosatellite DNA fragments, the purpose of which is to conduct genetic monitoring in rocks in order to preserve the allelofund of a few rocks. (3) The aim of the work was to identify intraspecific genetic variability of tarpan-like horses of the Polish konik breed and to establish phylogenetic links between ancient equids (Pleistocene horse, real tarpan) using ISSR - fingerprinting. The material for the assessment of intraspecific and interspecific genetic variability and the establishment of phylogenetic relationships between modern horses and fossil remains of ancient horses were horses of the Polish konik breed (10 heads) of the Yavoriv National Nature Park of the Lviv Region. and fossil bones of horses of the Pleistocene period (about 10 thousand years BC), metacarpal bone (os. tarsicentral). The bone was found in Novgorod-Siversky, Chernihiv region during quarry construction work. The excavations were carried out by PI Borisovsky in 1935. A tooth found in the village of Tarpan was used to study a wild tarpan horse (4.5 thousand years BC). Skibnytsia, Trostyanets district, Vinnytsia region. Excavations were conducted in 1959 by VM Danylenko. The paleontological material that was studied was provided by the Kyiv National Museum of Natural History of the National Academy of Sciences of Ukraine, Department of Paleontology. It was found that the species-specific spectra of PCR products obtained by ISSR-PCR for species E.caballus are fragments of 380-400 np and 500-520 np. The breed-specific fragments of the DNA molecule inherent in horses of the Polish konik breed include spectra of amplification products with a size of 680-710 np. It was found that the genetic distances between the amplicons of ISSR-PCR markers of Polish horses and fossil remains of a Pleistocene horse were 0.0881 and between the remains of a real tarpan - 0.0845. The low value of the share of polymorphic loci (P) and the index of polymorphic information content (PIC) was revealed, which indicates a high degree of genetic consolidation of horses of the Polish konik breed and possible reproductive isolation of the population. It was established that the spectra of amplification products of horses of the Polish horse and fossil remains of Pleistocene horse and real tarpan by 97% on the universal scale of dimension of ISSR fragments in np belonged to "light" (A-35 - A-25) and "medium" -25 - A-13), which is a specific characteristic of E. caballus species.

Integrative taxonomy of Serrasentis gibsoni n. sp. (Acanthocephala: Isthmosacanthidae) from flatfishes in the Gulf of Mexico

Abstract The Isthmosacanthidae acanthocephalan species of the genus Serrasentis are parasites of marine teleosts and an elasmobranch. In this study, Serrasentis gibsoni n. sp. is described from the intestines of four flatfish species (Paralichthyidae), namely Ancyclopsetta quadrocellata, Cyclopsetta chittendeni, Syacium gunteri, and S. papillosum from 10 oceanic sites in the Gulf of Mexico (GoM). Twenty sequences of the ‘barcoding’ region of cytochrome C oxidase subunit I gene were obtained from 20 adults of Serrasentis gibsoni n. sp. Additionally, five sequences of the barcoding region were obtained from five adults of rhadinorhynchid Gorgorhynchus lepidus from C. chittendeni, S. papillosum and one species of Haemulidae, Haemulom aurolineatum, from five oceanic sites from the GoM. Two phylogenetic approaches were followed: Bayesian inference and maximum likelihood. In both phylogenetic reconstructions, the sequences of Serrasentis gibsoni n. sp. were recovered as a monophyletic group within the genus Serrasentis and placed as a sister group to G. lepidus. However, due to the lack of molecular data for species of the Isthmosacanthidae and Rhadinorhynchidea, these phylogenetic inferences must be taken with caution. Serrasentis gibsoni n. sp. is the first species of Serrasentis described from Paralichthyidae flatfish species from marine waters of the Americas and from the GoM. Based on the barcoding data set analyzed, Serrasentis gibsoni n. sp. appears to have high intraspecific genetic variation; thus, it is necessary to continue exploring the genetic diversity of this species to infer its intraspecific evolutionary patterns.

Phylogeography of cliff racer (Platyceps rhodorachis Jan, 1865) from Punjab, Pakistan.

The present study reports the existence of cliff racer, Platyceps rhodorachis from the plains of Punjab, Pakistan. A total of 10 specimens were captured during the field surveys from June to September, 2018 from different sites of Punjab. Platyceps rhodorachis was identify on the basis of morphology and confirmed through COI gene sequences. The obtained DNA sequences have shown reliable and exact species identification. Newly produced DNA sequences of Platyceps rhodorachis were submitted to GenBank and accession numbers were obtained (MK936174.1, MK941839.1 and MT790210.1). N-J tree based on COI sequences of Platyceps rhodorachis clearly separated as out-group with other members of family Colubridae based on p-distance. The intra-specific genetic variation ranges from 12% to 18%. The DNA sequences of Platyceps rhodorachis kashmirensis, Platyceps rhodorachis ladacensis, Platyceps ventromaculatus, Platyceps ventromaculatus bengalensis and Platyceps ventromaculatus indusai are not available at NCBI to validate their taxonomic positions. In our recommendations, a large scale molecular based identification of Pakistan's herpetofauna is required to report more new or subspecies from country.