The connection between Trypanosoma cruzi transmission cycles by Triatoma brasiliensis brasiliensis: A threat to human health in an area susceptible to desertification in the Seridó, Rio Grande do Norte, Brazil

An outbreak of Chagas disease, possibly involving its vector Triatoma brasiliensis brasiliensis, was identified in the state of Rio Grande do Norte (RN). Given the historical significance of this vector in public health, the study aimed to evaluate its role in the transmission dynamics of the protozoan Trypanosoma cruzi in an area undergoing desertification in the Seridó region, RN, Brazil. We captured triatomines in sylvatic and anthropic ecotopes. Natural vector infection was determined using parasitological and molecular methods and we identified discrete typing units (DTUs) of T. cruzi by analyzing the COII gene of mtDNA, 24Sα rDNA, and mini-exon gene. Their blood meals sources were identified by amplification and sequencing of the mtDNA cytochrome b gene. A total of 952 T. b. brasiliensis were captured in peridomestic (69.9%) and sylvatic ecotopes (30.4%). A wide range of natural infection rates were observed in peridomestic (36.0% - 71.1%) and sylvatic populations (28.6% - 100.0%). We observed the circulation of TcI and TcII DTUs with a predominance of Tcl in sylvatic and peridomestic environments. Kerodon rupestris, rocky cavy (13/39), Homo sapiens, human (8/39), and Bos taurus, ox (6/39) were the most frequently detected blood meals sources. Thus, Triatoma b. brasiliensis is invading and colonizing the human dwellings. Furthermore, high levels of natural infection, coupled with the detection of TcI and TcII DTUs, and also the detection of K. rupestris and H. sapiens as blood meals sources of infected T. b. brasiliensis indicate a risk of T. cruzi transmission to human populations in areas undergoing desertification.

Genetic diversity and phylogenetic relationship of higher termite Globitermes sulphureus (Haviland)(Blattodea:Termitidae)

The subterranean higher termite Globitermes sulphureus (Blattodea: Termitidae), is a peridomestic forager and regarded as a significant pest in Southeast Asia. In this study, the populations of G. sulphureus from the USM main campus area were investigated based on partial sequences of the mitochondrial COII gene. The genetic diversity was determined using DnaSP v5 software while the phylogenetic relationship was defined using Neighbor-joining (NJ) and maximum likelihood (ML) methods using Molecular Evolutionary Genetics Analysis (MEGA 7) software. A total of 2 haplotypes were detected among the 5 sample sequences that differed by two variable sites. In addition, both phylogenetic trees gave similar topology and supporting the results from haplotype diversity. Based on the haplotype diversity and molecular phylogeny, it is proposed that geographic isolation and lack of human activities have contributed to the neutral genetic diversity of G. sulphureus.

MORPHOLOGICAL AND GENOTYPIC FEATURES OF THE POPULATIONS OF FLEAS OF THE GENUS XENOPSYLLA GLINKIEWICZ, 1907 (SIPHONAPTERA, PULICIDAE)

The paper presents the results of the study of some morphological and genotypic features of fleas of the genus Xenopsylla: X. gerbilli minax, X. skrjabini, X. hirtipes - the main vectors in the Central Asian natural desert plague focus. In order to identify population characteristics, for the first time we attempted both morphological analysis using the ImageJ computer program and subsequent data processing in a free statistical environment R version 4.0.0 with R Studio graphic shell, as well as genetic analysis of a fragment of a nucleotide sequence of the COII gene of fleas sampled in Pre-Ustyurt, Betpakdala and Pre-Pre-Balkhash autonomous plague foci. As a result of the study of morphometric indices of the main plague vectors in Kazakhstan, independent populations of three species of fleas of the genus Xenopsylla have been identified: the Betpakdala and Pre-Pre-Balkhash populations of X. gerbilli minax and X. hirtipes, as well as the Pre-Pre-Balkhash, Betpakdala and Pre-Usturt populations of X. skrjabini fleas.

Genetic diversity of indigenous catfish from Indonesia based on mitochondrial Cytochrome Oxidase Subunit II gene

Budiariati V, Susmiati T, Waroh S, Putri RCA, Widayanti R. 2021. Genetic diversity of indigenous catfish from Indonesia based on mitochondrial Cytochrome Oxidase Subunit II gene. Biodiversitas 22: 593-600. Catfish is one of the most demanding fish in Indonesia and served in a variety of traditional culinary. Due to their identical morphology and close relation between species in the order of Siluriformes, it is quite tricky to distinguish the species. This can be a threat to develop catfish production in Indonesia since there is a wide variety of catfish species in this mega biodiversity country. The study aimed to analyze the genetic diversity of Indonesian indigenous catfish especially those known as Baung fish by local people based on COII gene. The study also aimed to determine the phylogenetic relationship between the samples and compare them with the GenBank data. A total of 24 samples used in this study from 8 different rivers from 3 different islands and two samples were collected from coastal areas. The study results showed that there is genetic diversity of the Indonesian indigenous catfish based on COII gene. The sequences among 24 samples showed that from 691 nucleotides of COII gene, there were very subtle nucleotides differences of samples that originated from Bojonegoro, Magelang, and samples collected from Baru Beach, Yogyakarta. Based on COII amino acid sequences, 6 polymorphic amino acid sites were on-site number 64, 115, 123, 129, 144, and 165. The samples encoded LLB1 and LPB1 from Baru Beach, Yogyakarta, showed highest different amino acids in the six sites. Samples from the river of Central Java, Sumatra, and Kalimantan belonged to Bagridae family and consist of two different species Hemibagrus sp. and Mystus sp while samples from East Java belonged to Pangasiidae family. The Samples from coastal belonged to Ariidae family.

Chironomus calligraphus Goeldi, 1905 and C. hawaiiensis Grimshaw, 1901 are sibling species

Although Spies et al.’s (2002) thorough analysis of a small sample of the then available specimens of Chironomus calligraphus Goeldi,1905 suggested two distinctly different haplotypes in the mitochondrial COII gene, the corresponding morphological and cytological evidence kept the authors from concluding that there were two species involved. Further obstacles were unusual aspects of the molecular data and the occurrence of both these haplotypes in samples from the Brazilian type locality by Fittkau (1965) from which he had fixed a neotype. This neotype is slide mounted and can no longer yield molecular data. The present author’s analysis of additional material, including the available BARCODE sequences, has confirmed the existence of two forms, perhaps consistent with those found in the COII analysis, and with largely overlapping geographic distributions. One of these forms occurs in Hawaii where it is morphologically indistinguishable from C. hawaiiensis Grimshaw, 1901. It is recommended to apply this name, which takes nomenclatural precedence to the form found in Hawaii, and the name C. calligraphus to the form found to be more common in Fittkau’s type-locality samples.

Polymorphism of the СоІІ gene of honey bees in the western regions of Ukraine

Due to active human intervention in natural genetic and population processes, survival and distribution areas of honey bees have been negatively affected. Preservation of the gene pool of aboriginal bees that are well adapted to local environmental conditions is an urgent problem that cannot be solved without the use of molecular methods to monitor the genetic composition of local populations. This type of research requires the use of state-of-the-art approaches based on application of molecular markers. In the molecular taxonomy of insects, mitochondrial cytochrome oxidase genes are widely used to identify closely related forms. The peculiarity of mtDNA is that it is maternally inherited, and the mitochondrial molecular markers are not separated by recombination. The СоІІ gene encoding the second subunit of cytochrome oxidase is widely used to descriminate the subspecies of honey bee. Therefore, to assess the distribution of different subspecies / breeds of Apis mellifera in Ukraine, the 5′-region of the СоІІ gene was sequenced and compared for bees from different geographical regions. In the CoII gene, base substitutions were found, which makes it possible to distinguish between honey bees of the Carpathian and Ukrainian steppe breeds, which are widespread in Ukraine. It has been revealed that the distribution of these breeds does not always correspond to the official zoning. The widespread practice in Ukraine of transporting the genetic material of Apis mellifera from different regions leads to uncontrolled hybridization and poses a threat to the preservation of aboriginal breeds of honey bees.

Mitochondrial DNA Variation of Feral Honey Bees (Apis mellifera L.) from Utah (USA)

A study was conducted on the mitochondrial DNA genetic diversity of feral colonies and swarms of Apis mellifera from ten counties in Utah by sequencing the intergenic region of the cytochrome oxidase (COI-COII) gene region. A total of 20 haplotypes were found from 174 honey bee colony samples collected from 2008 to 2017. Samples belonged to the A (African) (48%); C (Eastern Europe) (43%); M (Western Europe) (4%); and O (Oriental) lineages (5%). Ten African A lineage haplotypes were observed with two unique to Utah among A lineage haplotypes recorded in the US. Haplotypes belonging to the A lineage were observed from six Utah counties located in the southern portion of the State, from elevations as high as 1357 m. All five C lineage haplotypes that were found have been observed from queen breeders in the US. Three haplotypes of the M lineage (n=7) and two of the O lineage (n=9) were also observed. This study provides evidence that honey bees of African descent are both common and diverse in wild populations of honey bees in southern Utah. The high levels of genetic diversity of A lineage honey bee colonies in Utah provide evidence that the lineage may have been established in Utah before the introduction of A lineage honey bees from Brazil to Texas in 1990.

Molecular Identification of some Indian Muscid flies (Diptera: Muscidae) based on mitochondrial gene COII

ABSTRACTTaxonomic identification of flies having medical and veterinary importance is often complicated due to the lookalike morphological characters. Molecular identification of five Indian muscid flies (Musca domestica, Musca sorbens, Musca crassirostris, Stomoxys calcitrans and Haematobia irritans) has been attempted on the basis of mitochondrial COII gene. Sequences of 500-520 bp were analysed and found to be A+T rich. Rate of transitions was higher than transversions. The average haplotype diversity was 0.833 and nucleotide diversity was 0.02547 within the different species, which were calculated with the DnaSP Version 5.0. The genetic distances calculated by K2P model, showed the interspecific distances range more than 8.2%, while the intraspecific distance range had not exceed 0.8%. The 1000 bootstrapped Neighbour-joining tree and Maximum likelihood tree were constructed to establish the phylogenetic relationship between the different muscid species. The results show the robustness of COII gene as a diagnostic marker. The data obtained from this study would be worthy for medical and veterinary entomologists for precise identification of imperative muscid species.