Forensic analysis of mosquito blood meal digestion process and the impact of heroin opiate: determination of the post-feeding interval as a PMI estimation.

Females of some mosquito species are anthropophilic, as they feed on human blood to support egg production and, hence, are forensically valuable if found at a crime scene. The present study investigated the blood meal digestion process in Culex pipiens L. both with and without heroin and proposed a method for estimating the post-feeding interval (PFI). Mosquitoes were fed on a control mouse, a heroin-injected mouse, or in vitro heroin-treated mouse blood. The blood meal digestion was then investigated at different hours post-feeding. Data showed that the blood meal size ingested by control mosquitoes was 0.681 ±â€…0.04 mg/mosquito and was completely digested within 45 h post-feeding. An estimation of the PFI was proposed in terms of the rate of hemoglobin (Hb) digestion. The blood meal size of the mosquitoes fed on the in vitro heroin-treated blood and the heroin-injected mouse was 0.96 ±â€…0.06 and 0.79 ±â€…0.01 mg/mosquito and was completely digested within 50 and 55 h post-feeding, respectively. The digestion of Hb started similarly in all experimental mosquitoes until 10 h post-feeding, after which it significantly decreased in heroin-treated blood meals compared with the control ones. This may suggest that heroin impacted the digestion process, as it took an extra 5-10 h to complete. These findings could be valuable in the forensic context since an estimation of PFI is proposed as a potential estimation of the postmortem interval (PMI). However, care should be taken as heroin in the host blood has significantly impacted the overall digestion process and, hence, may bias the PFI/PMI estimation.

Effect of cadmium on the regulatory mechanism of steroidogenic pathway of Leydig cells during spermatogenesis.

Cadmium is a male reproductive toxicant that interacts with a variety of pathogenetic mechanisms. However, the effect of cadmium on the regulatory mechanism of the steroidogenic pathway of Leydig cells during spermatogenesis is still ambiguous. Light microscopy, Western blot, immunohistochemistry, immunofluorescence, and quantitative polymerase chain reaction were performed to study the regulatory mechanism of the steroidogenic pathway of Leydig cells during spermatogenesis. The results indicated that in the control group, Leydig cells showed dynamic immunoreactivity and immunosignaling action with a strong positive significant secretion of 3ß-hydroxysteroid hydrogenase (3ß-HSD) in the interstitial compartment of the testis. Leydig cells showed a high active regulator mechanism of the steroidogenic pathway with increased the proteins and genes expression level of steroidogenic acute regulatory protein (STAR), cytochrome P450 cholesterol (CYP11A1), cytochrome P450 cholesterol (CYP17A1), 3ß-hydroxysteroid hydrogenase (3ß-HSD) 17ß-hydroxysteroid hydrogenase (17ß-HSD), and androgen receptor (AR) that maintained the healthy and vigorous progressive motile spermatozoa. However, on treatment with cadmium, Leydig cells were irregularly dispersed in the interstitial compartment of the testis. Leydig cells showed reduced immunoreactivity and immunosignaling of 3ß-HSD protein. Meanwhile, cadmium impaired the regulatory mechanism of the steroidogenic process of the Leydig cells with reduced protein and gene expression levels of STAR, CYP11A1, CYP17A1, 3ß-HSD, 17ß-HSD, and AR in the testis. Additionally, treatment with cadmium impaired the serum LH, FSH, and testosterone levels in blood as compared to control. This study explores the hazardous effect of cadmium on the regulatory mechanism of the steroidogenic pathway of Leydig cells during spermatogenesis.

A preliminary investigation of rabbit carcass decomposition and attracted ants (Hymenoptera: Formicidae) on the seaward coastal beach of Al-Jubail City, Saudi Arabia.

The current study was carried out in the seaward coastal beach environment of Al-Jubail City, Saudi Arabia, to analyze the rabbit carcass decomposition process, the succession pattern of associated ants, and their potential utility in forensic investigation. Experiments were conducted over a 4-season course (from autumn 2018 to summer 2019). A total of 9 species belonging to the 2 subfamilies, Myrmicinae and Formicinae, were recorded. The myrmicine species were Crematogaster aegyptiaca Mayr, 1862; Messor ebeninus Santschi, 1927; Messor foreli Santschi, 1923; and Monomorium abeillei Andre, 1881. The formicine species were Camponotus xerxes Forel, 1904; Cataglyphis albicans (Roger, 1859); Cataglyphis hologerseniCollingwood & Agosti, 1996; Cataglyphis viaticoides (André, 1881); and Nylanderia jaegerskioeldi (Mayr, 1904). M. abeillei was the only species recorded in all 4 seasons, while M. abeillei and C. albicans were the dominant species in summer and C. aegyptiaca and C. albicans in spring. Diversity was lowest in the autumn, with only 4 species recorded. The COI gene sequences of 5 species have been successfully deposited in the GenBank database for the first time. In total, 4 carcass decomposition stages were observed, with the longest duration in winter (13 days), the shortest in summer (11 days), and in between for both autumn and spring. Most ant species were present during both decay and dry stages, while M. abeillei, C. aegyptiaca, M. ebeninus, and C. albicans were observed in all decomposition stages. These data may indicate that ants on this coastal beach showed seasonal and geographical succession patterns that could be taken into consideration in forensic investigations.

Transgenerational effect of Afidopyropen on Bemisia tabaci Gennadius (Homoptera: Aleyrodidae).

Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) is the most devastating insect-pest in cotton crop. It is vector of the cotton leaf curl virus (CLCV) and is responsible for huge losses to cotton industry in Pakistan and worldwide. It is mainly controlled by insecticides but the injudicious use of insecticides has resulted in insecticide resistance and population resurgence in addition to various harmful effects on the humans, non-target organisms and the environment. Transgenerational studies are very helpful to choose a best insecticidal option. In the current study, age-stage two-sex life table analysis was used to identify transgenerational effects of sublethal doses of afidopyropen. The adults of B. tabaci were treated with three concentrations of afidopyropen i.e., LC10, LC30 and LC50. The results indicated significant changes in the progeny i.e. the fecundity decreased in treated population; and female and male longevity of their progeny were more in control as compared to treated populations. Similarly, population parameters like intrinsic rate of growth (r), net reproductive rate (R0) and limiting rate of growth (λ) were significantly decreased in the treated adult progeny with values of 0.08-0.11, 4.85-7.46 and 1.09-1.12 per day, respectively. Based on the reduced biotic potential, afidopyropen can be suggested as an effective alternative option for the management of B. tabaci.

Impact of Envenomation With Snake Venoms on Rabbit Carcass Decomposition and Differential Adult Dipteran Succession Patterns.

The current study investigates the postmortem successional patterns of necrophagous dipteran insects and the rabbit carcass decomposition rate upon envenomation with snake venom. In total, 15 rabbits, Oryctolagus cuniculus domesticus L. (Lagomorpha, Leporidae), were divided into 3 groups (5 rabbits each; n = 5); the first and second groups were injected with lethal doses of venoms from the Egyptian cobra, Naja haje L. (Squamata, Elapidae), and the horned viper, Cerastes cerastes L. (Squamata, viperidae), respectively. The third group (control) was injected with 0.85% physiological saline and euthanized with CO2. The carcass decomposition stages: fresh, bloating, decay, and dry were recorded and monitored. Data revealed that envenomation shortened the decomposition process by 3 d, 20% shorter than the control. The overall succession pattern of fly species revealed a lower abundance during the fresh stage, which peaked during the decay stage, and declined to the minimum number in the dry stage at the end of the 15-d experimental duration. A total of 2,488 individual flies, belonging to 21 species of 10 families, were collected from all experimental carcasses. The Calliphoridae, Muscidae, and Sarcophagidae were the most abundant and diverse families, whereas the other seven families were rare and least abundant. Although C. cerastes venom was significantly less lethal than N. haje, it showed a faster carcass decomposition process and a higher impact on fly abundance. These data showed that envenomation impacts insect succession and carcass decomposition, which should be taken into account when using insects in forensic investigations since envenomation with snake venoms is one of the leading causes of death worldwide.

Evaluation of Insecticidal Potentials of Five Plant Extracts against the Stored Grain Pest, Callosobruchus maculatus (Coleoptera: Bruchidae).

Plant based insecticides are considered among the most economic and ecofriendly chemicals for the protection of plants and stored grains. The cowpea weevil (Callosbruchus maculatus) causes more than 90% damage to sored grains in three to six months. The current study investigates insecticidal potentials of five selected botanicals: Melia azedarach, Nicotiana rustica, Azadirachta indica, Nicotiana tabacum and Thuja orientalis. They are explored at six different concentrations (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%) against C. maculatus and compared to effects of distilled water which is used as a control. Toxicities of 3%(V/V) extracts of N. tabacum, N. rustica, A. indica and T. orientalis against C. maculatus were 100%, 86.11%, 80.56% and 72.22%, respectively. Maximum mortality was caused by N. tabacum and N. rustica (100%), followed by A. indica (82%), whereas minimum mortality was observed in T. orientalis (64%) at 2.5%. Several phytochemicals, alkaloids, saponins, diterphenes, phytosterol, flavonoids and phenols were identified in N. tabacum and N. rustica, while few were present in A. indica. Phytosterol was present in greatest abundance. Saponins were only detected in aqueous extracts of N. rustica and N. tabacum. Taken together, these results indicate the utility of N. tabacum, N. rustica and A. indica as potential botanicals to control pest beetle and cowpea weevil.

Chemical Composition and Evaluation of Antifungal and Insecticidal Activities of Essential Oils Extracted from Jambosa caryophyllus (Thunb.) Nied: Clove Buds.

Jambosa caryophyllus has been used in traditional phytotherapy as a treatment against infections. In the present work, essential oils extracted from clove buds (Jambosa caryophyllus ) (EO-JC) were investigated for their composition, antifungal, and insecticidal properties. Extraction of EO-JC was performed by use of hydrodistillation using a Clevenger-type apparatus, and the EOs were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). Antifungal activity of EO-JC was evaluated by the use of solid-state diffusion (disc method) and microdilution to determine the minimum inhibitory concentration (MIC), against three strains of fungus, Aspergillus niger, Aspergillus flavus, and Fusarium oxysporum. Insecticidal activity of EO-JC against the cowpea weevil, Callosobruchus maculatus, was determined to assess utility of EO-JC to control this pest. Several exposures including inhalation and contact were used to determine lethality, as well as the repulsion test was conducted at concentrations of 4, 8, 16, and 32 µL EO-JC. Characterization of EO-JC by GC/MS revealed 34 compounds accounting for 99.98% of the mass of the extract. The predominant compound was eugenol (26.80%) followed by ß-caryophyllene (16.03%) and eugenyl acetate (5.83%). The antifungal activity of EO-JC on solid media exhibited inhibitions in the range of 49% to 87%, and MIC was between 3.125 and 7.80 µg EO-JC/mL. Insecticidal activity, as determined by the use of the inhalation test, and expressed as the LD50 and LD95 after 96 hours of exposure was 2.32 and 21.92 µL/L air, respectively. In the contact test, a 96-hour exposure resulted in LD50 and LD95 of 5.51 and 11.05 µL/L of air, respectively. EO-JC exhibited insecticidal activity against fungi and pest chickpea weevil.

Molecular Identification of Newly Recorded Louse Columbicola tschulyschman Eichler (Phthiraptera: Philopteridae) From Saudi Arabia With a Note on Genus Columbicola spp. Phylogeny.

Chewing lice comprise a large group of ectoparasites that colonize and adversely affect several domestic and wild birds including pigeons. In Saudi Arabia, there is a lack of studies describing such ectoparasites and their infestation rates. Through this work, a new record, Columbicola, tschulyschman Eichler (C. tschulyschman Eichler) was collected from domestic pigeons (Columba livia domestica, Linnaeus). The collected C. tschulyschman Eichler was morphologically identified based on specific taxonomic keys. Mitochondrial (COI) and nuclear (EF-1α) gene fragments were used for molecular identification and phylogenetic reconstruction. In this study, the C. tschulyschman Eichler accounted for around 69.40%. To our knowledge, this is the first report of C. tschulyschman Eichler in Riyadh, Saudi Arabia. To improve the tree topology and differentiate between genera, further studies should utilize the 16s rRNA.

A Novel Protein Elicitor (PELL1) Extracted from Lecanicillium lecanii Induced Resistance against Bemisia tabaci (Hemiptera: Aleyrodidae) in Gossypium hirsutum L.

Protein elicitors play a key role in signaling or displaying plant defense mechanism and emerging as vital tools for biocontrol of insects. This study was aimed at the characterization of the novel protein elicitor isolated from entomopathogenic fungi Lecanicillium lecanii (V3) strain and its activity against whitefly, Bemisia tabaci, in cotton (Gossypium hirsutum L.). The sequence of purified elicitor protein showed 100% similarity with hypothetical protein LEL_00878 (Cordyceps confragosa RCEF 1005) (GenBank accession no. OAA81333.1). This novel protein elicitor has 253 amino acid residues and 762 bp with a molecular mass of 29 kDa. Their combatant protein was expressed in Escherichia coli using pET-28a (+) plasmid. Bioassay was revealed to quantify the impact of numerous concentrations of protein (i.e., 58.32, 41.22, and 35.41 µg/ml) on the fecundity rate of B tabaci on cotton plants. Bioassay results exhibited a significant effect (P ≤ 0.001) of all the concentrations of protein on the fecundity rate of B. tabaci. In addition, the gene expression analysis found a significant upregulation of the major genes associated with salicylic acid (SA) and jasmonic acid (JA) defense pathways in elicitor protein-treated plants. Our results showed that the potential application of novel protein elicitor derived from Lecanicillium lecanii will be used as future biointensive controlling approaches against whitefly, Bemisia tabaci.

Ameliorative effect of L-carnitine on lambda-cyhalothrin-induced anatomical and reproductive aberrations in albino mice.

The objective of this research was to look at how the pesticide lambda-cyhalothrin (LCT) affected the liver, kidney, testis, and ovary of albino mice; and on morphological and skeletal features of the newborn of treated females. The study also aimed to test the ameliorative effects of L-carnitine (LC) against (LCT). Five sets of mice were created, Group 1 acted as the control, while Group 2 received a high dose of LCT, Group 3 received a high dose of LCT + LC, Group 4 received a low dose of LCT that was a residue of in khat (Qat), and Group 5 received a low dose of LCT + LC. The findings revealed that the treated groups' body weights were reduced significantly, whereas the absolute and relative weights of the liver in all groups were statistically decreased insignificantly. There were histopathological changes in the tissues in groups 2 and 4. While the tissues of the ovary and testis showed recovery in groups 3 and 5. When compared to the control group, the values of the seminiferous tubules parameters were statistically significant in the 3 and 5 groups. The newborn had a high dose of pesticides and showed some malformations in the skeleton. However, in group 3 the skeletal malformation was minimized and in-group 5 the skeleton malformations had completely disappeared. It could be concluded that LCT is highly harmful to mouse tissues and caused neonatal malformations, whereas LC has a marked protective effect against LCT.

Correction: Path analysis based on genetic association of yield components and insects pest in upland cotton varieties.

[This corrects the article DOI: 10.1371/journal.pone.0260971.].

Effect of temperature & humdity on population dynamics of insects' pest complex of cotton crop.

The current study was directed to investigate the effect of temperature and humidity on insect pest complex of cotton. This study was carried out on the farmer field of a farmer of MouzaMehraywala tehsil and district Rajanpur southern part of the Punjab, Pakistan (29.1044° N, 70.3301° E) in the month of May, 2019 to November 2019. The climatic conditions of the study site were; a Rajanpur lie on 96m above sea level Rajanpur has a desert climate. During the year, there is virtually no rainfall. The average temperature in Rajanpur is 26.0°C | 78.8°F. Precipitation here is about 205 mm / 8.1 inch per year. Our results indicate that's the correlation of temperature (minimum and maximum), humidity (minimum and maximum), rainfall and weather condition (clear or cloud), it is clear that except temperature there is a positive correlation of jassid population. While among the relation of jassid with different factor there is very weak relation with jassid population regarding temperature (-0.001), the relation of humidity, rainfall and sky condition with jassid population is positive and moderate (0.520, 0.668 & 0.575 respectively), while the relation of jassid population among these factor is significant except temperature. The results indicate that's the correlation of temperature, humidity, rainfall and weather condition, it is clear that there is positive correlation of thrips population. While among the relation of thrips with different factor there is very weak relation of thrips population with temperature (.103), the relation of humidity, rainfall and sky condition with thrips population is positive and moderate (.515.751& .577 respectively), while the relation thrips population among these factor is significant except temperature. The results indicate that's correlation of temperature, humidity, rainfall and weather condition, it is clear that there is positive correlation of Whitefly population. While among the relation of Whitefly with different factors there is very moderate relation of Whitefly population with temperature (.076), the relation of humidity, rainfall and sky condition with Whitefly population is negative and moderate (-.051.-.368 & -.559 respectively), while the relation Whitefly population among these factor is significant except temperature.

Microbiological investigation study for Apis mellifera yemenitica and Apis mellifera carnica bee venoms on selected bacterial strains.

Bees are one of the ancient and the most social insects worldwide. They are of great economic and medical importance. Bee venom (BV) has many therapeutic effects and has been used since ancient times for the treatment of many diseases. The present study aimed to evaluate and compare the antibacterial effect of BV from two different bee subspecies Apis mellifera yemenitica (A. m. yemenitica) (indigenous strain) and Apis mellifera carnica (A. m. carnica) (carniolan strain) against selected Gram-positive and Gram-negative bacteria. Experimentally, venoms were extracted using an electrical venom collector from honey bee colonies of the subspecies, A. m. yemenitica and A. m. carnica, in Hail, Saudi Arabia. Each venom was tested against selected medically important Gram-negative strains, Salmonella Typhimurium, Pseudomonas aeruginosa, and Escherichia coli, while Staphylococcus aureus was selected as Gram-positive test organism. The minimum inhibitory concentration (MIC) method was used to compare the effect of BV from the two subspecies on the growth of the selected bacterial strains. Results showed that BV from both subspecies could equally inhibit the growth of Salmonella Typhimurium, Pseudomonas aeruginosa, and Escherichia coli at an MIC of 10 mg/ml. However, S. aureus was inhibited by an MIC of 5 and 10 mg/ml of BV from A. m. carnica and A. m. yemenitica, respectively. This suggested that the BV of the carnica subspecie was more inhibitory to this Gram-positive pathogen than its counterpart produced by the yemenitica subspecies. The present study shows that bee venom has a promising antibacterial effect.

Awareness and perception of malaria and dengue at school and college level in the district of Multan.

The purpose of this study is to examine the awareness and perception of malaria and dengue fever in Multan Punjab, Pakistan while taking into account the important role of government policies and other variables. The goal of this study is to examine the awareness of students in Multan, Pakistan on malaria and dengue. This study is based on a quantitative approach of secondary evidence from scientific journals and questionnaire surveys. It is also based on observational evidence gathered in Multan Punjab Pakistan, in a field study. The survey with school children, teachers and healthcare professionals were both formal and semi-structuralize. Studies have found that malaria and dengue mainly affect children's schooling through their absence, but can also induce brain loss and cognitive disability. In questionnaires, students were seen to have different understanding of the illness, but also to be able to serve as agents of health reform only through teachers. A sample size of 500 respondents has been selected from different colleges of district Multan Punjab, Pakistan. Correlation technique is used for the data analysis. According to our results it is concluded that the students at college level are aware of malaria and dengue diseases, but they are not capable of engaging and serving as agents for health reform. On the basis of results it is recommended that students must teach about epidemics diseases regarding how to handle these diseases.

Molecular Detection of Tick-Borne Rickettsial Pathogens Associated with the Arabian Camel (Camelus dromedarius) in Riyadh and the Eastern Region, Saudi Arabia.

BACKGROUND: In Saudi Arabia, records on molecular identification of tick-borne infections in camels are relatively scarce; few molecular epidemiological studies have been conducted. OBJECTIVE: This study aimed to find Anaplasma species and Piroplasma spp. in camels from Riyadh and the Eastern Region, Saudi Arabia. ANIMALS: A total of 1369 blood samples were collected from camels from Riyadh and the Eastern Region and analyzed for the DNA of Anaplasma and Piroplasma species by polymerase chain reaction (PCR). RESULTS: Piroplasma spp. infection was not observed in any of the blood samples. 616 camels (44.99%) were found to be positive for Anaplasma infection by PCR targeting the 16S rRNA and COX1 genes. Six Anaplasma sequences for the 16S rRNA gene (OK481101-OK481106) were deposited in GenBank and six for the COX1 gene (OK490994-OK490999). They showed 98.3% and 62.7% similarities with Anaplasma marginale (A. marginale) detected in Kenya and Brazil, respectively. Phylogenetic studies revealed that the 12 sequences reported in this study were closely related; they were found in the same cluster as A. marginale isolates previously recorded in South Africa, Brazil, USA, China, and Israel. CONCLUSION: Finally, 12 Anaplasma sequences closely related to A. marginale were detected in camels in Riyadh and the Eastern Region, Saudi Arabia. Camels in these areas were confirmed to be free of Piroplasma.

Identifying two moth species (Lepidoptera: Ditrysia) from Saudi Arabia using mitochondrial 16S rRNA sequences.

The mitochondrial genetic markers are considered useful tools for discrimination between more closely related lepidopteran taxa. Therefore, the present study aimed to investigate the role of mitochondrial (mt) 16 s rRNA gene in the determination of the taxonomic position for two moth species within Ditrysia clade. Maximum likelihood analysis has indicated a well-supported dendrogram based on the Tamura-Nei model for the recovered lepidopterans. The mt 16 s rRNA query sequences from 24 species within seven families were analyzed. This analysis and bootstrap confidence revealed two major clades representing Glossata suborder within Lepidoptera, with a close relationship of Noctuoidea + (Pyraloidea (Hesperioidea + Papilionoidea)). The subfamily Heliothinae forming a sister group with Risobinae (Noctinae + Hadeninae). In addition, there is a clear observation about the close relation between Phycitinae + Galleriinae within Pyraloidea and Cyrestinae + Limenitidinae within Papilionoidea. The present study supported that the Helicoverpa and Meroptera species are the first accounts of these genera inhabiting Saudi Arabia.

Identification of Theileria spp. in sheep and goats from Jeddah, Saudi Arabia, using molecular techniques.

BACKGROUND: Thileriosis is a tick -born disease caused by hemoprotozoan parasites which has global veterinary and economic implications. METHODS: Blood samples were collected from 216 sheep and 83 goats from Jeddah, Saudi Arabia, were analyzed to determine whether the animals were infected with Theileria spp. parasites. The parasites were detected using a polymerase chain reaction (PCR) targeting the gene of 18S rRNA followed by sequencing. RESULTS: According to obtained findings, Theileria spp. were detected in sheep (57.8%, 48/83) and goats (51.9%, 112/216). Phylogenetic analysis to sequence data showed that T. ovis identified in this study were found to be closely connected to an isolate from Turkey, with 84.4-99.8% pairwise identity and 52.35-99.79% coverage.

Path analysis based on genetic association of yield components and insects pest in upland cotton varieties.

Gossypium hirsutum L. is also called upland cotton or Mexican cotton. It is the most widely cultivated species of cotton in the whole world. Globally, about 90% of all cotton production comes from the cultivars derived from this species. Some genetic parameters like monopodial branches per plant, sympodial branches per plant, sympodial branch length, bolls per plant, boll weight, sympo-boll distance, Ginning Out Turn%, staple length (rg = 0.9199**), and fiber strength along with seed cotton yield were evaluated for their potential utilization via selection in seed cotton yield improvement. Significant positive genetic correlations were estimated for monopodial branches per plant (rg = 0.9722**), sympodial branches per plant (rg = 0.7098**), sympodial branch length (rg = 0.617**), bolls per plant (rg = 0.8271**), boll weight (rg = 0.8065**), sympo-boll distance (rg = 0.6507**), Ginning Out Turn (GOT)% (rg = 0.7541**), staple length (rg = 0.9199**), and fiber strength (rg = 0.7534**) with seed cotton yield. A path analysis of all the yield traits under study revealed strong positive direct effects of monopodial branch length (1.1556), sympo-boll distance (0.8173) and staple length (0.7633), while plant height exerted a highly strong direct negative effect (-1.2096) on yield. It is concluded that a direct selection based on monopodial branch length and sympo-boll distance, and staple length is effective, whereas, monopodial branch length, and sympodial branch length are good selection indicators via bolls per plant for yield improvement in cotton.

Heteromicrocotyla polyorchis Unnithan, 1961 (Monogenea: Heteromicrocotylidae), a gill parasite of the yellow-spotted trevally, Carangoides fulvoguttatus (Carangidae) from Saudi Arabia: Morphology and phylogeny.

Little information for parasitic infections of Carangoides fulvoguttatus was recorded. The present study was intended to investigate the gill parasite Heteromicrocotyla polyorchis of this fish and to provide a full morphological description and clarify its taxonomic status through phylogenetic analysis of the 28S rRNA gene region. A total of sixty fish specimens have been collected from the studied area (the Red Sea in Jeddah Province, Saudi Arabia) and gills were isolated and examined for identification of parasites. Using light electron microscopy, the recovered monogenean parasite's morphology was exhaustively characterized and described. Microscope examinations found that this parasite species represent Heteromicrocotyla polyorchis, and it could be distinguished from congeners of the same genus by armed genital atrium and cirrus sac, follicular post-ovarian testes, unique shape and number of clamps on both haptor sides, and the dorsally curved tip of the male copulatory organ. Morphological features were combined with molecular analysis of the 28S rRNA gene region. The selected gene for the isolated Heteromicrocotyla species was analyzed using appropriate primers to assist in phylogeny with those in the GenBank database. The present monogenean species was characterized by unique genetic sequences that were analyzed and deposited in the GenBank for the first time under the accession number MW406473. Phylogenetic analyses reported that the maximum identity between the current Heteromicrocotyla species and taxa of Heteromicrocotylidae was between 91.42 and 92.09% and confirmed its taxonomic status in this family with a well-distinct clade. The present study supported the second report of H. polyorchis as carangid fish ectoparasites and investigates the first appearance in C. fulvoguttatus inhabiting Saudi Arabia.