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Booth W. Population genetics as a tool to understand invasion dynamics and insecticide resistance in indoor urban pest insects. CURRENT OPINION IN INSECT SCIENCE 2024; 62:101166. [PMID: 38253200 DOI: 10.1016/j.cois.2024.101166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 01/24/2024]
Abstract
Many indoor urban pest insects now show a near-global distribution. The reasons for this may be linked to their cryptic behaviors, which make unintentional transport likely, tied to their reliance on human-mediated dispersal that can result in spread over potentially long-distances. Additionally, numerous species exhibit an array of mechanisms that confer insecticide resistance. Using population genetics, it is possible to elucidate the genetic characteristics that define globally successful indoor urban pest insect species. Furthermore, this approach may be used to determine the frequency and distribution of insecticide resistance. Here, I review the recent literature that utilizes population genetic analyses in an effort to identify the characteristics that help explain the success of indoor urban pests.
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Affiliation(s)
- Warren Booth
- Department of Entomology, Virginia Polytechnic Institute and State University, 1015 Life Science Circle, 215C Steger Hall, Blacksburg, VA, USA.
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Köseoğlu AE, Paltacı S, Can H, Giantsis IA, Güvendi M, Demir S, Döşkaya M, Ün C. Applicability evaluation of mtDNA based molecular identification in mosquito species/subspecies/biotypes collected from Thessaloniki, Greece. Vet Parasitol Reg Stud Reports 2023; 41:100869. [PMID: 37208079 DOI: 10.1016/j.vprsr.2023.100869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/08/2023] [Accepted: 04/03/2023] [Indexed: 05/21/2023]
Abstract
The genus Culex, containing many described species, plays a role as a vector for diseases of medical and veterinary importance worldwide. Among these species, Culex pipiens is one of the most widespread mosquitoes and is classified into two biological forms (biotypes), named as Culex pipiens pipiens and Culex pipiens molestus. Due to similar morphological structure between these biotypes, morphological identification is inadequate. Thus, molecular methods have been developed and are considered more reliable, some of which are based on analyses of mitochondrial DNA. The aim of the present study was to evaluate the applicability and reliability of mtDNA based molecular identification methodologies. Initially, mosquito specimens (n = 100) collected from Thessaloniki, Greece were morphologically analyzed. Then, mitochondrial cox1 sequencing and PCR-RFLP methods were used to confirm the morphological identification results as well as to discriminate species and subspecies/biotype of Culex pipiens complex. According to morphological identification results, Culex pipiens complex (n = 92), Culex modestus (n = 6) and Culex theileri (n = 2) were detected. Using mtDNA sequencing, all Culex modestus and Culex theileri samples were confirmed whereas 86 of Culex pipiens complex were detected as Culex pipiens but surprisingly the remaining six of them were detected as Culex quinquefasciatus. Among Culex pipiens specimens, PCR-RFLP detected that frequency of Culex pipiens pipiens (85%; 85/100) was very high compared to Culex pipiens molestus (1%, 1/100). In conclusion, this study shows the necessity of use of molecular methods beside morphological methods for especially specimens detected as Culex pipiens. Also, it was shown that mtDNA PCR-RFLP methodology represents a well-established alternative for Culex biotypes identification.
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Affiliation(s)
- Ahmet Efe Köseoğlu
- Biruni University Faculty of Engineering and Natural Sciences, Department of Molecular Biology and Genetics, Istanbul, Turkey
| | - Satı Paltacı
- Ege University Faculty of Science, Department of Biology, Molecular Biology Section, İzmir, Turkey
| | - Hüseyin Can
- Ege University Faculty of Science, Department of Biology, Molecular Biology Section, İzmir, Turkey.
| | - Ioannis A Giantsis
- University of Western Macedonia Faculty of Agricultural Science, Department of Animal Science, Greece
| | - Mervenur Güvendi
- Ege University Faculty of Science, Department of Biology, Molecular Biology Section, İzmir, Turkey
| | - Samiye Demir
- Ege University Faculty of Science, Department of Biology, Zoology Section, İzmir, Turkey
| | - Mert Döşkaya
- Ege University Faculty of Medicine, Department of Parasitology, İzmir, Turkey
| | - Cemal Ün
- Ege University Faculty of Science, Department of Biology, Molecular Biology Section, İzmir, Turkey
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Population Genetic Structure of Anisakis simplex Infecting the European Hake from North East Atlantic Fishing Grounds. Animals (Basel) 2023; 13:ani13020197. [PMID: 36670737 PMCID: PMC9854729 DOI: 10.3390/ani13020197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/06/2023] Open
Abstract
The European hake, one of the most commercially valuable species in ICES fishing areas, is considered an important neglected source of zoonotic risk by nematode parasites belonging to the genus Anisakis. Merluccius merluccius is, by far, the most important host of Anisakis spp. at the European fishing grounds, in terms of demographic infection values, and carries the highest parasite burden. These high parasite population densities within an individual fish host offer a chance to explore new sources of variations for the genetic structure of Anisakis spp. populations. A total of 873 Anisakis spp. third-stage larvae, originally sampled from viscera and muscular sections of hake collected at ten fishing grounds, were primarily identified using ITS rDNA region as molecular marker. After that, we used mtDNA cox2 gene to reveal the high haplotype diversity and the lack of genetic structure for A. simplex. Dominant haplotypes were shared among the different fishing areas and fish sections analyzed. Results indicate a clear connection of A. simplex from European hake along the Northern North Sea to the Portuguese coast, constituting a single genetic population but revealing a certain level of genetic sub-structuring on the Northwest coast of Scotland. This study also provides useful information to advance the understanding of parasite speciation to different fish host tissues or microenvironments.
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Güvendi M, Can H, Köseoğlu AE, Erkunt Alak S, Kandemir Ç, Taşkın T, Sürgeç E, Demir S, Değirmenci Döşkaya A, Karakavuk M, Gül A, Döşkaya M, Gürüz AY, Ün C. Investigation of the genetic diversity and flea-borne pathogens in Ctenocephalides felis samples collected from goats in İzmir and Şanlıurfa provinces of Turkey. Comp Immunol Microbiol Infect Dis 2022; 90-91:101896. [DOI: 10.1016/j.cimid.2022.101896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/28/2022] [Accepted: 10/05/2022] [Indexed: 11/30/2022]
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García-Sánchez AM, Zurita A, Cutillas C. Morphometrics as a Complementary Tool in the Differentiation of Two Cosmopolitan Flea Species: Ctenocephalides felis and Ctenocephalides canis. INSECTS 2022; 13:insects13080707. [PMID: 36005332 PMCID: PMC9409166 DOI: 10.3390/insects13080707] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 07/26/2022] [Accepted: 08/02/2022] [Indexed: 05/30/2023]
Abstract
Fleas (Siphonaptera) are one of the most important ectoparasites that represent a potential danger for the transmission of pathogens in our environment. The cat flea, Ctenocephalides felis (Bouché, 1835), and the dog flea, Ctenocephalides canis (Curtis, 1826) are among the most prevalent and most frequently studied species throughout the world. However, the variations observed in their morphological characteristics complicate their correct identification, especially when there is a lack of access to the equipment and funds required to carry out molecular biology techniques. With the objective to provide an additional tool to help in the differentiation of Ctenocephalides species, a principal component analysis was carried out for the first time in the present work on populations of C. felis and C. canis from countries in three continents, namely Spain (Europe), South Africa (Africa) and Iran (Asia). The factor maps assisted in the differentiation of both species and the detection of differences in overall size, although morphological ambiguity prevented the delimitation in populations of the same species. Thus, morphometrics represents a complementary tool to other traditional and modern techniques, with great potential to assist in the differentiation of fleas, particularly species that have historically been difficult to identify.
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Zhang Y, Nie Y, Li LY, Chen SY, Liu GH, Liu W. Population genetics and genetic variation of Ctenocephalides felis and Pulex irritans in China by analysis of nuclear and mitochondrial genes. Parasit Vectors 2022; 15:266. [PMID: 35897029 PMCID: PMC9327250 DOI: 10.1186/s13071-022-05393-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 07/04/2022] [Indexed: 11/11/2022] Open
Abstract
Background Fleas are the most economically significant blood-feeding ectoparasites worldwide. Ctenocephalides felis and Pulex irritans can parasitize various animals closely related to humans and are of high veterinary significance. Methods In this study, 82 samples were collected from 7 provinces of China. Through studying the nuclear genes ITS1 and EF-1α and two different mitochondrial genes cox1 and cox2, the population genetics and genetic variation of C. felis and P. irritans in China were further investigated. Results The intraspecies differences between C. felis and P. irritans ranged from 0 to 3.9%. The interspecific variance in the EF-1α, cox1, and cox2 sequences was 8.2–18.3%, while the ITS1 sequence was 50.1–52.2%. High genetic diversity was observed in both C. felis and P. irritans, and the nucleotide diversity of cox1 was higher than that of cox2. Moderate gene flow was detected in the C. felis and P. irritans populations. Both species possessed many haplotypes, but the haplotype distribution was uneven. Fu's Fs and Tajima's D tests showed that C. felis and P. irritans experienced a bottleneck effect in Guangxi Zhuang Autonomous Region and Henan province. Evolutionary analysis suggested that C. felis may have two geographical lineages in China, while no multiple lineages of P.irritans were found. Conclusions Using sequence comparison and the construction of phylogenetic trees, we found a moderate amount of gene flow in the C. felis and P. irritans populations. Both species possessed many haplotypes, but the distribution of haplotypes varied among the provinces. Fu’s Fs and Tajima’s D tests indicated that both species had experienced a bottleneck effect in Guangxi and Henan provinces. Evolutionary analysis suggested that C. felis may have two geographical lineages in China, while no multiple lineages of P.irritans were found. This study will help better understand fleas' population genetics and evolutionary biology. Graphical Abstract ![]()
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Affiliation(s)
- Yu Zhang
- Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Yu Nie
- Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Le-Yan Li
- Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Shu-Yu Chen
- Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128, Hunan, China
| | - Guo-Hua Liu
- Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128, Hunan, China.
| | - Wei Liu
- Research Center for Parasites & Vectors, College of Veterinary Medicine, Hunan Agricultural University, Changsha, 410128, Hunan, China. .,The Key Laboratory of Animal Vaccine & Protein Engineering, Changsha, 410128, Hunan, China.
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Misbah S, Low VL, Mohd Rahim NF, Jaba R, Basari N, Ya'cob Z, Abu Bakar S. Mitochondrial Diversity of the Asian Tiger Mosquito Aedes albopictus (Diptera: Culicidae) in Peninsular Malaysia. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:865-873. [PMID: 35178576 DOI: 10.1093/jme/tjac014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Indexed: 06/14/2023]
Abstract
Aedes albopictus is one of the main mosquito vectors responsible for transmitting arboviruses to humans and animals. The ability of this mosquito to support virus transmission has been linked to vector competence, which is partly attributed to the genetic disparities in Ae. albopictus population. At present, little is known about the biologically important traits of Ae. albopictus in Malaysia. Thus, the study aims to determine the genetic variation of Ae. albopictus based on the mitochondria-encoded sequences of cytochrome oxidase subunit I (COI). A statistical parsimony network of 253 taxa aligned as 321 characters of the COI gene revealed 42 haplotypes (H1-H42), of which H1 was the most widespread haplotype in Peninsular Malaysia. Three highly divergent haplotypes (H21, H30, and H31) were detected from the northern population. Overall, haplotype and nucleotide diversities were 0.576 and 0.003, respectively, with low genetic differentiation (FST = 0.039) and high gene flow (Nm = 12.21) across all populations.
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Affiliation(s)
- Suzana Misbah
- Biological Security and Sustainability (BioSES) Research Interest Group, Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia
- Institute of Marine Biotechnology, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia
| | - Van Lun Low
- Higher Institution Centre of Excellence (HICoE), Tropical Infectious Diseases Research & Education Centre (TIDREC), Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Nurul Farhana Mohd Rahim
- Higher Institution Centre of Excellence (HICoE), Tropical Infectious Diseases Research & Education Centre (TIDREC), Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Rizzuaeammie Jaba
- Biological Security and Sustainability (BioSES) Research Interest Group, Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia
| | - Norasmah Basari
- Biological Security and Sustainability (BioSES) Research Interest Group, Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia
| | - Zubaidah Ya'cob
- Higher Institution Centre of Excellence (HICoE), Tropical Infectious Diseases Research & Education Centre (TIDREC), Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Sazaly Abu Bakar
- Higher Institution Centre of Excellence (HICoE), Tropical Infectious Diseases Research & Education Centre (TIDREC), Universiti Malaya, 50603, Kuala Lumpur, Malaysia
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Azrizal-Wahid N, Sofian-Azirun M, Low VL, Chen CD, Shohaimi S. Cat Owners' Perceptions toward Flea Infestation and Flea-borne Diseases: Impact for Public Health and Community Awareness. J APPL ANIM WELF SCI 2021; 25:1-17. [PMID: 34493142 DOI: 10.1080/10888705.2021.1975539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
A structured questionnaire was distributed to a total of 531 cat owners in Peninsular Malaysia to evaluate their perceptions toward fleas and flea-borne diseases (FBD) using a knowledge-attitude-practice (KAP) approach. This study showed that majority of cat owners (50.5%) had a moderate level of knowledge on fleas, while 65.3% of them had a relatively low level of knowledge on FBD. However, most of them had positive attitudes (87.9%) and good practices (94.5%) toward efforts on prevention from flea infestation and FBD. Statistical analysis showed significant associations between knowledge on fleas and FBD toward demographic and pet ownership profiles of the respondents. Educated cat owners from urban area were more likely to have positive attitudes toward prevention of fleas and FBD. Female cat owners with monthly income of RM 5,001-7,000 ($1143-1600) were more likely to have good practices. Middle-aged cat owners showed the highest odds toward both positive attitudes and good practices. Correlation analyses indicated significant linear relationships between both knowledge, which were also associated with attitudes, but not with practices.
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Affiliation(s)
- Noor Azrizal-Wahid
- Universiti Malaya, Kuala Lumpur, Malaysia.,Institute for Advanced Studies, Universiti Malaya, Kuala Lumpur, Malaysia.,Department of Biology, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor Darul Ehsan, Malaysia
| | - Mohd Sofian-Azirun
- Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur, Malaysia
| | | | - Chee Dhang Chen
- Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Shamarina Shohaimi
- Department of Biology, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor Darul Ehsan, Malaysia.,Institute for Mathematical Research, Universiti Putra Malaysia, Serdang, Selangor Darul Ehsan, Malaysia
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Zhang Y, Nie Y, Deng YP, Liu GH, Fu YT. The complete mitochondrial genome sequences of the cat flea Ctenocephalides felis felis (Siphonaptera: Pulicidae) support the hypothesis that C. felis isolates from China and USA were the same C. f. felis subspecies. Acta Trop 2021; 217:105880. [PMID: 33662336 DOI: 10.1016/j.actatropica.2021.105880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 11/28/2022]
Abstract
The cat flea Ctenocephalides felis (Siphonaptera: Pulicidae) is the most important ectoparasite in cats and dogs worldwide. Over the years, there has been much dispute regarding the taxonomic and systematic status of C. felis. Mitochondrial (mt) genome sequences are useful genetic markers for the identification and differentiation of ectoparasites, but the mt genome of C. felis and its subspecies has not yet been entirely characterized. In the present study, the entire mt genome of C. f. felis from China was sequenced and compared with that of C. felis from the USA. Both contain 37 genes and a long non-coding region of >6 kbp. The molecular identity between the Chinese and American isolates was 99%, except for the non-coding region. The protein-coding genes showed differences at both the nucleotide (1.2%) and amino acid (1%) levels. Interestingly, the cox1 gene of the Chinese isolate had an unusual putative start codon (TTT). Taken together, our analyses strongly support the hypothesis that C. felis isolates from China and the USA were the same C. f. felis subspecies. The mt genome sequence of the C. f. felis China isolate presented in this study provides useful molecular markers to further address the taxonomy and systematics of C. felis.
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Affiliation(s)
- Yu Zhang
- Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, 410128, China
| | - Yu Nie
- Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, 410128, China
| | - Yuan-Ping Deng
- Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, 410128, China
| | - Guo-Hua Liu
- Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, 410128, China; Hunan Co-Innovation Center of Animal Production Safety, Changsha, Hunan Province, 410128, China.
| | - Yi-Tian Fu
- Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, 410128, China.
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Azrizal-Wahid N, Sofian-Azirun M, Low VL. Flea-borne pathogens in the cat flea Ctenocephalides felis and their association with mtDNA diversity of the flea host. Comp Immunol Microbiol Infect Dis 2021; 75:101621. [PMID: 33609991 DOI: 10.1016/j.cimid.2021.101621] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/27/2021] [Accepted: 02/04/2021] [Indexed: 11/18/2022]
Abstract
Flea-borne pathogens were screened from 100 individual cat fleas using a PCR approach, of which 38 % were infected with at least one bacterium. Overall, 28 % of the flea samples were positive for Bartonella as inferred from ITS DNA region. Of these, 25 % (7/28) were identified as Bartonella clarridgeiae, 42.9 % (12/28) as Bartonella henselae consisted of two different strains, and 32.1 % (9/28) as Bartonella koehlerae, which was detected for the first time in Malaysia. Sequencing of gltA amplicons detected Rickettsia DNA in 14 % of cat flea samples, all of them identified as Rickettsia asembonensis (100 %). None of the flea samples were positive for Mycoplasma DNA in 16S rRNA gene detection. Four fleas were co-infected with Bartonella and Rickettsia DNAs. Statistical analyses reveal no significant association between bacterial infection and mtDNA diversity of the cat flea. Nevertheless, in all types of pathogen infections, infected populations demonstrated lower nucleotide and haplotype diversities compared to uninfected populations. Moreover, lower haplotype numbers were observed in infected populations.
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Affiliation(s)
- Noor Azrizal-Wahid
- Higher Institution Centre of Excellence (HICoE), Tropical Infectious Diseases Research & Education Centre (TIDREC), Universiti Malaya, 50603, Kuala Lumpur, Malaysia; Institute for Advanced Studies, Universiti Malaya, 50603, Kuala Lumpur, Malaysia; Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400, Serdang, Selangor Darul Ehsan, Malaysia
| | - Mohd Sofian-Azirun
- Institute of Biological Sciences, Faculty of Science, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Van Lun Low
- Higher Institution Centre of Excellence (HICoE), Tropical Infectious Diseases Research & Education Centre (TIDREC), Universiti Malaya, 50603, Kuala Lumpur, Malaysia.
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New taxonomic and evolutionary insights relevant to the cat flea, Ctenocephalides felis: A geographic perspective. Mol Phylogenet Evol 2020; 155:106990. [PMID: 33096232 DOI: 10.1016/j.ympev.2020.106990] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 11/22/2022]
Abstract
The cat flea, Ctenocephalides felis, is an obligate haematophagous ectoparasite of wildlife and domestic cats and dogs worldwide. Since cat fleas can affect the health of humans and their pets, an uncertain taxonomy of this taxon can greatly inhibit pest and disease management. To address the evolution and taxonomy of the cat flea, we set out to determine 1) how many genetically distinct taxa exist, 2) whether there is morphological support for the genetically distinct taxa, and 3) the role of host range and paleoclimatic events in speciation. We collected a total of 3352 fleas sampled from 576 domestic cats and dogs as well as 10 wildlife species across 30 localities in South Africa. A total of three flea genera, five species, and three of the currently recognized cat flea subspecies, C. f. damarensis, C. f. strongylus and C. f. felis were obtained. Geometric morphometric analyses on head shape were performed on 68 female and 107 male cat flea individuals. Principal component analysis demonstrated large overlap in head shape variation between C. f. strongylus and C. f. felis, rendering this character not useful for phylogenetic inferences. DNA was extracted from 188 Ctenocephalides spp. and mitochondrial COII and nuclear EF1-α sequences were generated. Bayesian and Maximum Likelihood analyses as well as a TCS parsimony haplotype network of the mitochondrial DNA confirmed the presence of three well supported monophyletic clades. These assemblages did not fully corroborate the existence of the three C. felis subspecies. A single well-supported molecular clade included only C. f. damarensis morphotypes that were mostly collected from wildlife. The recognition of this subspecies as a distinct taxon was further corroborated by sequence distances and also the number of plantar spiniform bristles on fore-tarsi V in males. Despite the overall lack of support for the recognition of C. f. damarensis and C. f. strongylus, a geographic trend was visible whereby one genetic lineage corresponded to the western dryer hot subregion, whereas the other was found throughout the region. Bayesian dating suggested that these two clades diverged during the early Pliocene (4.18 mya), a date that corresponds well with the establishment of a dry hot climate in the west of southern Africa. If so, the off-host environment, particularly temperature and humidity, are important factors to consider in the evolution of the cat flea. The present study rejects recent assertions that the three cat flea subspecies are valid entities and rather point to a situation where more sampling is required before the taxonomic status of C. f. damarensis can be resolved.
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