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International Journal for Parasitology: Parasites and Wildlife logoLink to International Journal for Parasitology: Parasites and Wildlife
. 2024 Nov 30;26:101025. doi: 10.1016/j.ijppaw.2024.101025

Species description and molecular analysis of a hard tick (Amblyomma cordiferum) parasitizing wild Taiwan cobra snake (Naja atra) in southern Taiwan

Li-Lian Chao a,b,1, Tien-Hsi Chen c,1, Esmeralda Erazo b, Chien-Ming Shih a,b,c,d,⁎
PMCID: PMC11721908  PMID: 39802583

Abstract

Species description based on the pictorial keys of morphological characters of female Amblyomma cordiferum tick parasitizing wild Taiwan cobra snake (Naja atra) was firstly described in Taiwan. Molecular analysis based on the 16S mitochondrial gene sequences was performed by comparing eight A. cordiferum ticks from Taiwan with other Amblyomma species documented in GenBank. In addition, two Dermacentor and two Rhipicephalus species were used as outgroups. All these Taiwan specimens constructing a monophyletic group which is genetically affiliated with A. cordiferum and it can be discriminated from other Amblyomma species. This study provides the first species description and determines the genetic identity of adult A. cordiferum ticks parasitizing wild Taiwan cobra snake. Further investigations focused on its ability to carry various tick-borne pathogens will help to illustrate the medical importance on human health in Taiwan.

Keywords: Tick, Amblyomma cordiferum, Cobra snake, Naja atra, Taiwan

Graphical abstract

Image 1

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Highlights

  • •

    Species description of Amblyomma cordiferum tick infesting Taiwan cobra snake.

  • •

    First molecular analysis of Am. cordiferum tick based on the 16S mitochondrial gene in Taiwan.

  • •

    Highlights the possible epidemiological impacts of this tick species on human health.

1. Introduction

The significant impacts of ticks on animal and human health are attributed to their ability to transmit various pathogens and their detrimental effects to injure livestock (Jongejan and Uilenberg, 2004). The Amblyomma cordiferum Neumann, is a rare tick species which has been recorded from Indonesia, Malaysia, Singapore, Taiwan, Thailand and Western Samoa (Petney and Keirans, 1995; Barnard and Durden, 2000; Voltzit and Keirans, 2002; Robbins, 2005; Norval et al., 2005, 2008; Tan et al., 2019; Amarga et al., 2023). In previous studies, this tick speices had been recorded as a common ectoparasite of several reptilian hosts (Hoogstraal et al., 1968; Barnard and Durden, 2000; Norval et al., 2005, 2008; Tan et al., 2019; Amarga et al., 2023). Although this tick species had been collected from various localities and snake hosts of Taiwan (U.S. National Tick Collection, R. G. Robbins, personal communication), direct evidence of A. cordiferum parasitizing wild Taiwan cobra snake (Naja naja atra) has never been reported in Taiwan.

The Taiwan cobra snake also known as the Chinese cobra (Naja atra), is one of the most prevalent venomous snakes in Taiwan, which are responsible for approximately 20% of venomous snakebites in Taiwan (Chen et al., 2015). These snakebites cause necrosis of wound tissue due to the actions of cytotoxins in the venom and confer a high risk of wound infection (Huang et al., 2012; Hsieh et al., 2017; Mao et al., 2018; Yeh et al., 2021). The geographical distribution of this snake species has been recorded in southeastern China, Hong Kong, northern Laos, northern Vietnam and Taiwan (Wang and Wang, 1956; Zhao and Adler, 1993; Wuster, 1996; Chan, 2006; Amarga et al., 2023). In Taiwan, this cobra species has been assessed as The IUCN Red List of Threatened Species in 2011 and its impact on species conservation for Amblyomma ticks requires further clarification.

Due to the global impact of climatic change, tick species parasitizing wild hosts are highly variable around the world (Guglielmone et al., 2014). Although the A. cordiferum tick is commonly observed on snakes (Norval et al., 2005, 2008; Tan et al., 2019; Amarga et al., 2023), the morphological features of A. cordiferum tick is poorly described in Taiwan. In addition, genetic identity of this tick species parasitizing wild Taiwan cobra snake has never been reported in Taiwan. Thus, the objectives of this study are to demonstrate the key morphological characters of A. cordiferum tick collected from wild Taiwan cobra snake and to determine the genetic identity of this tick species based on the phylogenetic analysis of 16S mitochondrial gene.

2. Materials and methods

2.1. Tick specimens collected from Taiwan cobra snake

Adult ticks were collected from a Taiwan cobra snake captured on February 20, 2023 at Xin-Yuan District in Pingtung County of southern Taiwan (22° 52′N, 120° 48′E). Briefly, the attached female ticks (8 A. cordiferum) were removed from the body of this cobra snake and then transferred to the laboratory. Further cleaning by sonication in 75% ethanol solution for 5–10 min was also performed. After washing twice with sterile distilled water, all processed ticks were stored at −20 °C until further analysis (Chao et al., 2022a).

2.2. Morphological and molecular identification of tick specimens

Single tick specimen was placed on a glass slide and observed with a stereo microscope (SMZ 1500, Nikon, Japan) equipped with a fiber optic lamp. The morphological characters of the collected ticks were recorded for species identification, as previously described (Chao et al., 2022a). Molecular identification of tick species was also performed by targeting the 16S mitochondrial gene, as previously described (Black and Piesman, 1994; Chao and Shih, 2016).

2.3. Total genomic DNA extraction from tick specimens

In general, each tick specimen was homogenized in a microcentrifuge tube filled with 180-μL of lysing buffer solution provided by the DNeasy Blood & Tissue Kit (Cat. No. 69506, Qiagen, Taipei, Taiwan) and followed by homogenization with a TissueLyser II apparatus (Qiagen, Hilden, Germany), as recommended by the manufacturer. The homogenate was centrifuged at room temperature and the supernatant fluid was removed for further process. Follow the final filtration, the filtrated fluid was collected and the DNA concentration was determined with a DNA calculator (Epoch, microplate spectrophotometer; BioTek-Agilent, Santa Clara, CA, USA). All extracted DNA was stored at −80 °C for further analysis.

2.4. DNA amplification by polymerase chain reaction (PCR) assay

Extracted DNA samples of tick specimens were used as a template for PCR amplification. A specific primer set of forward (16S + 1) and reverse (16S-1) primers were designed to target the mitochondrial 16S rDNA gene, as described previously (Black and Piesman, 1994). All PCR reagents and Taq polymerase were obtained and used as recommended by the supplier (Takara Shuzo, Kyoto, Japan). In general, a 25-μL reaction mixture was performed with a Veriti thermocycler (Applied Biosystems, Taipei, Taiwan) and the PCR amplification was amplified for 40 cycles with the following conditions: denaturation at 92 °C for 1 min, annealing at 54 °C for 35 s, and extension at 72 °C for 90 s, as described previously (Black and Piesman, 1994; Chao et al., 2009). The amplified DNA products were electrophoresed on 2% agarose gels in Tris-Borate-EDTA (TBE) buffer and visualized under ultraviolet light after staining with ethidium bromide. A 100-bp DNA ladder (GeneRuler, Thermo Fisher Scientific, Taipei, Taiwan) was used as the standard marker for comparison. A negative control with the same amount of sterile distilled water was included in parallel with each amplification.

2.5. Phylogenetic analysis of amplified sequences

Each 10-μL of selected PCR products appeared with clear bands on the agarose gel was submitted for DNA sequencing (Mission Biotech, Taipei, Taiwan). After further purification, sequencing reactions were conducted with 25 cycles with the same conditions and primer set for DNA amplification by the dye-deoxy terminator reaction method using the Big Dye Terminator Cycle Sequencing Kit in an ABI Prism 377-96 DNA Sequencer (Applied Biosystems, Foster City, CA, USA). The resulting sequences were initially edited using BioEdit software (v.5.3) and aligned with CLUSTAL W software (Thompson et al., 1994), and the aligned sequences of 16S mitochondrial genes from 8 Taiwan specimens (A. cordiferum) were compared with sequences of A. cordiferum from Malaysia and A. helvolum from Thailand, and six other Amblyomma species from various biological and geographical origins available from GenBank. In addition, two species of Dermacentor and Rhipicephalus ticks were served as outgroups. Phylogenetic analysis was performed by the maximum likelihood (ML) and unweighted pair group with arithmetic mean (UPGMA) methods to estimate the phylogeny of the entire alignment using the MEGA X software package (Kumar et al., 2018). Phylogenetic trees were constructed and performed with 1000 bootstrap replications to evaluate the reliability of the construction, as described previously (Felsenstein, 1985).

3. Results

3.1. Adult female ticks collected from Taiwan cobra snake

A total of 8 female hard ticks were removed from the wound part of a wild Taiwan cobra snake captured in southern Taiwan. A wild Taiwan cobra snake observed with a body wound (Fig. 1A) and the typical hood mark shape of horseshoe is observed in throat area linked to head (Fig. 1B). Attached hard ticks feeding on the wound part of Taiwan cobra snake (Fig. 1C).

Fig. 1.

Fig. 1

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Light micrographs of Taiwan cobra snake (Naja atra) captured in southern Taiwan. (A) A wild Taiwan cobra snake observed with a body wound (long arrow). (B) The typical hood mark shape of horseshoe (short arrow) is observed in throat area linked to head. (C) Several hard ticks (long arrow) feeding on the wound area of this snake.

3.2. Description of morphological characters for species identification of hard ticks

The removed ticks were morphological identified based on the morphological features of female A. cordiferum ticks including long-narrowed palps and oval porose areas on the rectangular basis capituli (short arrow in Fig. 2A). The scutum of A. cordiferum is rhomboid with deep punctations in lateral anterior part and transparent eyes in lateral margin (long arrow and arrowhead in Fig. 2A). Ventrally, the genital aperture (arrowhead in Fig. 2B) and the anus (short arrow in Fig. 2B) is situated at the anterior and posterior part of abdomen, respectively. The Coxae I-II of A. cordiferum possess small, triangular internal spurs (short arrows in Fig. 2C) that are absent on coxae III-IV and all coxae I-IV possess larger, distinct triangular external spurs (long arrows in Fig. 2C). The genital aperture is situated at a level between coxae II and III of A. cordiferum (arrowhead in Fig. 2C). The elongate hypostome bears numerous sharp teeth with a dental formula of 4/4 for A. cordiferum (long arrow in Fig. 2D). Laterally, the comma-shaped spiracular plates (long arrow in Fig. 2E) contain large maculae with lateral protrution to the external margin of A. cordiferum (long arrow in Fig. 2F) and the anal groove forms a visible loop around the posterior of annus (short arrow in Fig. 2F). In addition, the dichotomous key to separate A. cordiferum from its congeners of female stage in Taiwan was modified from R. G. Robbins (personal communication) that was shown as below.

Fig. 2.

Fig. 2

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Light micrographs of female Amblyomma cordiferum tick collected from the wild Taiwan cobra. (A) Dorsal view showing long-narrowed palps and oval porose areas on the rectangular basis capituli (short arrow). The scutum is rhomboid with deep punctations in lateral anterior part and transparent eyes in lateral margin (long arrow and arrowhead). (B) Ventrally, the genital aperture (arrowhead) and the annus (short arrow) is situated at the anterior and posterior part of abdomen, respectively. (C) The Coxae I-II possess short, triangular internal spurs (short arrows) that are absent on coxae III-IV and all coxae I-IV possess distinct external spurs that are broad and triangular (long arrows). The genital aperture is situated at a level between coxae II and III (arrowhead). (D) The elongate hypostome bears numerous sharp teeth with a dental formula of 4/4 (long arrow). (E) Laterally, the comma-shaped spiracular plates (long arrow) were observed. (F) The spiracular plates contain large maculae with lateral protrution to the external margin (long arrow) and the anal groove forms a visible loop around the posterior of anus (short arrow).

3.2.1. Keys to the female stage of Amblyomma species in Taiwan

  • 1.

    Eyes absent; very small species, idiosoma about 2.90 mm L, 2.70 W, unengorged … … … … … … … … … … … … … … … Amblyomma varanense (Supino, 1897)

Eyes present; larger species … … … … … … … … … … … … … … … … … … … … … … … …2.

  • 2.

    Dental formula 3/3; a small species, idiosoma about 3.60 L, 2.90 W, unengorged … … … …… … … … … … … … … … … … … Amblyomma helvolum Koch, 1844

Dental formula 4/4 … … … … … … … … … … … … … … … … … … … … … … … … … … … 3.

  • 3.

    Scutum inornate … … … … … … … … … … … … … … … … … … … … … … … … …. … ….0.4

Scutum ornate … … … … … … … … … … … … … … … … … … … … … … … … … …. … …0.5.

  • 4.

    Coxae II and III each with a single, very small triangular spur; a parasite of sea snakes … … … … … … … … … … … … … … ….Amblyomma nitidum Hirst and Hirst, 1910

Coxae I and II each with two spurs, the internal 1 min, tubercle-like; Coxae I to IV each with larger, triangular external spurs … ….Amblyomma cordiferum Neumann, 1899.

  • 5.

    Innermost (4th) file of hypostome with denticles smaller than those in files 1–3; spurs of coxae II and III rounded, much broader than long; dorsal foveae small; a parasite of large wild and domestic mammals … … … … … … … …Amblyomma testudinarium Koch, 1844

Denticles of innermost hypostome file about equal in size to those of other files; spurs of coxae II and III triangular, as long as broad or not much broader than long; dorsal foveae very large; a parasite of testudines … … … … … … … … ….Amblyomma geoemydae Cantor, 1847.

3.3. Molecular analysis of genetic relatedness of collected ticks

All sequences of 16S rDNA fragments from 8 representative tick specimens (A. cordiferum) of Taiwan used in this study were aligned and compared with the downloaded sequences from GenBank; i.e. A. cordiferum from Malaysia, A. helvolum from Thailand and six other Amblyomma species plus two Dermacentor species and two Rhipicephalus species serving as outgroups (Table 1). The aligned nucleotide sequences of A. cordiferum were highly conserved within the Taiwan specimens. All these Taiwan specimens constructed with a monophyletic clade were genetically affiliated within the same genospecies of A. cordiferum with highly homogeneous sequences similarity (99%–100%) and that can be distinguished from other Amblyomma spp. as well as the outgroup species of Dermacentor and Rhipicephalus (Table 2). Furthermore, intra- and inter-species analysis based on genetic distance (GD) values revealed a lower level of GD (GD < 0.044) within the same lineage of A. cordiferum and a higher level of GD (GD > 0.112) as compared with the other Amblyomma species as well as the outgroup species (GD > 0.163) (Table 2).

Table 1.

Phylogenetic analysis based on mitochondrial 16S rDNA genes of Amblyomma ticks collected from Taiwan and other tick species used in this study.

Species/strain Origin of tick strain
 16S rDNA gene accession number
Biological Geographic
Taiwan strains rowhead
 PT-XY-20230220-Amb-PEF12 Snake (Naja naja atra) Taiwan OR742080
 PT-XY-20230220-Amb-PEF13 Snake (Naja naja atra) Taiwan OR742082
 PT- XY-20230220-Amb-PEF6 Snake (Naja naja atra) Taiwan OR742083
 PT- XY-20230220-Amb-PEF7 Snake (Naja naja atra) Taiwan OR742084
 PT- XY-20230220-Amb-PEF9 Snake (Naja naja atra) Taiwan OR742085
 PT- XY-20230220-Amb-PEF11 Snake (Naja naja atra) Taiwan OR742086
 PT- XY-20230220-Amb-PEF10 Snake (Naja naja atra) Taiwan OR742093
 PT- XY-20230220-Amb-PEF8 Snake (Naja naja atra) Taiwan OR763830
Amblyomma cordiferum
 T26 Snake Malaysia MK301096
Amblyomma helvolum
 Unknown Snake Thailand KC170738
Amblyomma geoemydae
 AG-E Turtle Japan AB819163
Amblyomma nitidum
 AN-B Sea krait Japan AB819166
Amblyomma dubitatum
C254-15 Opossum Brazil KU894374
Amblyomma coelebs
 Ac1 Jaguar Belize KU001160
Ambloymma braziliense
 Unknown Unknown Brazil FJ424399
Ambloymma incisum
 Aincisum1 Unknown Argentina KM519939
Dermacentor andersoni
 SL17 Unknown Canada FM955614
Dermacentor variabilis
 Unknown Unknown USA L34300
Rhipicephalus sanguineus
 Unknown Dog Thailand KC170744
Rhipicephalus appendiculatus rowhead
 Unknown Unknown USA L34301
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Note: The bold GenBank numbers were submitted by this study.

Table 2.

Intra- and Inter-species analysis of genetic distance values based on the 16S mitochondrial gene sequences between Amblyomma cordiferum tick strains collected from Taiwan and other tick strains documented in GenBank.

Tick strains 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
1. Amblyomma cordiferum (MK301096) –
2. PT-20230220-Amb-PEF13 (Taiwan) 0.041 –
3. PT-20230220-Amb-PEF12 (Taiwan) 0.033 0.008 –
4. PT-20230220-Amb-PEF11 (Taiwan) 0.037 0.004 0.004 –
5. PT-20230220-Amb-PEF10 (Taiwan) 0.039 0.002 0.006 0.002 –
6. PT-20230220-Amb-PEF9 (Taiwan) 0.039 0.002 0.006 0.002 0.000 –
7. PT-20230220-Amb-PEF8 (Taiwan) 0.044 0.002 0.010 0.006 0.004 0.004 –
8. PT-20230220-Amb-PEF7 (Taiwan) 0.044 0.006 0.010 0.006 0.008 0.008 0.008 –
9. PT-20230220-Amb-PEF6 (Taiwan) 0.044 0.002 0.010 0.006 0.004 0.004 0.000 0.008 –
10. Amblyomma helvolum (KC170738) 0.136 0.122 0.112 0.117 0.120 0.120 0.120 0.125 0.120 –
11. Amblyomma geoemydae (AB819163) 0.106 0.092 0.082 0.087 0.089 0.089 0.092 0.094 0.092 0.105 –
12. Ambltomma nitidum (AB819166) 0.106 0.099 0.090 0.094 0.097 0.097 0.097 0.102 0.097 0.143 0.097 –
13. Amblyomma dubitatum (KU894374) 0.132 0.125 0.115 0.120 0.123 0.122 0.125 0.127 0.125 0.112 0.110 0.113 –
14. Amblyomma coelebs (KU001160) 0.159 0.161 0.150 0.155 0.159 0.158 0.158 0.164 0.158 0.122 0.116 0.150 0.082 –
15. Amblyomma braziliense (FJ424399) 0.167 0.157 0.146 0.152 0.155 0.154 0.154 0.160 0.154 0.121 0.117 0.141 0.109 0.088 –
16. Dermacentor andersoni (FM955614) 0.186 0.174 0.163 0.169 0.172 0.172 0.174 0.177 0.174 0.175 0.129 0.159 0.138 0.149 0.150 –
17. Rhipicephalus appendiculatus (L34301) 0.225 0.219 0.208 0.214 0.217 0.217 0.219 0.222 0.219 0.173 0.180 0.197 0.179 0.194 0.193 0.189 －
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Note: The pairwise distance calculation was performed by the method of Kimura 2-parameter, as implemented in MEGA X (Kumar et al., 2018).

3.4. Phylogenetic analysis of tick specimens

Based on the sequences alignment of mitochondrial 16S rDNA, the phylogenetic relationships among 20 strains of hard ticks was analyzed in this study. Bootstrap analysis was used to analyze the repeatability of the clustering of specimens represented in phylogenetic trees. Phylogenetic trees constructed by both ML (Fig. 3) and UPGMA (Fig. 4) analyses showed congruent basal topologies with eight major branches of distinguished clades (Fig. 3, Fig. 4). All these Taiwan specimens constitute a monophyletic clade closely affiliated with the lineage of A. cordiferum. It can easily be distinguished from the other lineages of Amblyomma and the outgroup species (Dermacentor and Rhipicephalus) with a bootstrap value of 100 in ML and UPGMA analyses (Fig. 3, Fig. 4). The phylogenetic tree of ML analysis was identical to the UPGMA tree and strongly supports the separation of Taiwan ticks of A. cordiferum lineage from other lineages of Amblyomma ticks with a bootstrap value of 100 (Fig. 3, Fig. 4).

Fig. 3.

Fig. 3

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Phylogenetic relationships based on 16S mitochondrial gene sequences by ML method. Eight Taiwan specimens of Amblyomma cordiferum ticks collected from wild Taiwan cobra were compared with eight other Amblyomma spp., and two Dermacentor and two Rhipicephalus species used as outgroups. The tree was constructed and analyzed by the maximum likelihood (ML) method using 1000 bootstraps replicates. Numbers at the nodes indicate the reliability (%) of each branch of the tree. Branch lengths are drawn in proportion to the estimated sequence divergence.

Fig. 4.

Fig. 4

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Phylogenetic relationships based on 16S mitochondrial gene sequences by UPGMA method. Eight Taiwan specimens of Amblyomma cordiferum ticks collected from wild Taiwan cobra were compared with eight other Amblyomma spp., and two Dermacentor and two Rhipicephalus species as outgroups. The tree was constructed and analyzed by the unweighted pair group with arithmetic mean (UPGMA) method using 1000 bootstraps replicates. Numbers at the nodes indicate the reliability (%) of each branch of the tree. Branch lengths are drawn in proportion to the estimated sequence divergence.

3.5. Nucleotide sequence accession numbers

PCR-amplified nucleotide sequences of 16S mitochondrial genes of 8 Taiwan specimens of A. cordiferum determined in this study have been registered and assigned the GenBank accession numbers (Table 1). The GenBank accession numbers of the eight other Amblyomma species and the two outgroups of Dermacentor and Rhipicephalus species are also shown in Table 1.

4. Discussion

Due to the highly genetical conservation and strictly maternal inheritance, the molecular identification based on the mitochondrial 16S gene sequences seems to provide a feasible and convenient tool for genetic identification and species discrimination among various populations of hard ticks. Indeed, genetic analysis based on the mitochondrial 16S gene sequences for various Ixodes ticks allows quantitative assessment of their genetic relatedness (Black and Piesman, 1994; Caporale et al., 1995; Norris et al., 1996; Xu et al., 2003). In our previous reports, sequence analyses of the mitochondrial 16S genes have also been used to discriminate the genetic difference and to analyze the phylogenetic relationships among various species of hard ticks in Taiwan (Chao et al., 2009, 2022a, 2022b; Chao and Shih, 2016). Results from this study reveal that the nucleotide composition of the mitochondrial 16S genes derived from A. cordiferum ticks of Taiwan is genetically monophyletic with highly homogeneous sequences (99.2%–100% similarity) affiliated with the same genospecies of A. cordiferum tick from Malaysia (Table 2). Thus, our results provide the first genetic identification based on the mitochondrial 16S ribosomal gene and demonstrate the first convincing sequences of A. cordiferum ticks (Table 2) parasitized on wild Taiwan cobra snake.

The natural hosts and life cycle of A. cordiferum ticks in Taiwan remain unclear. In Taiwan, our previous studies have described the tick species of A. helvolum infested on Taiwan stink snake (Elaphe carinata) and green iguanas (Iguana iguana) in the field (Chao et al., 2013, 2023), and the A. cordiferum ticks have been recorded as an ectoparasite of Taiwanese rat snake (Elaphe taeniura friesei) and various venomous snakes (Amarga et al., 2023). The worldwide reports of A. cordiferum ticks have been found associated with several snake species (Ophiophagus hannah, Python reticulatus, Ptyas mucosa, and Elaphe taeniura friesei) (Barnard and Durden, 2000; Norval et al., 2005, 2008; Tan et al., 2019; Amarga et al., 2023), rodents (Audy et al., 1960) and fruit bat (Cynopterus horsfieldii) (Ahama et al., 201335). In addition, the A. cordiferum tick is known to reproduce parthenogenetically and can complete its life cycle in 168–209 days under laboratory conditions (Ho and Ismail, 1984; Oliver, 1989). In this study, all adult females of A. cordiferum were collected from infested wild Taiwan cobra snake. However, no males and immature stage (larvae and nymphs) of ticks were collected. Further investigations focused on the seasonal prevalence of the live stages of this tick species on various reptilian hosts may facilitate our understanding of the natural history of A. cordiferum tick in Taiwan.

The reptiles have been recognized as the carriers for various vector ticks that can transmit tick-borne pathogens (TBP) (Karesh et al., 2005). Indeed, the reptilian tick species of Am. helvolum has been reported as the vector tick responsible for the transmission of various TBP, such as Rickettsia spp., Francisella-like endosymbionts, Anaplasma spp. and Ehrlichia spp. in Thailand and Malaysia (Sumrandee et al., 2014; Kho et al., 2015; Rakthong et al., 2016). However, A. cordiferum was only recorded as the possible vector of an unidentified virus in Malaysia (Audy et al., 1960). In Taiwan, accidental transportation of A. cordiferum had been reported on a king cobra snake imported from Malaysia (Norval et al., 2009). However, no TBP have been discovered in this tick species. Thus, routine screening for TBP in A. cordiferum ticks parasitized on various reptiles in Taiwan is essential for understanding the potential risk for human infections.

5. Conclusion

This study describes the key morphological characters of A. cordiferum tick parasitizing wild cobra snake in Taiwan and determines its genetic identity based on the molecular analysis of 16S mitochondrial gene. Further study focused on various tick-borne pathogens carried by A. cordiferum ticks will help to illustrate the medical importance of this tick species on human health in Taiwan.

CRediT authorship contribution statement

Li-Lian Chao: Writing – original draft, Supervision, Methodology, Investigation, Formal analysis, Data curation. Tien-Hsi Chen: Visualization, Validation, Methodology, Investigation, Formal analysis, Data curation. Esmeralda Erazo: Methodology, Investigation, Formal analysis, Data curation. Chien-Ming Shih: Writing – review & editing, Writing – original draft, Visualization, Supervision, Resources, Project administration, Funding acquisition, Formal analysis, Conceptualization.

Ethical approval

The collection of ticks from reptiles was assisted by veterinary practitioner and approved by the Institutional Animal Care and Use Committee (IACUC) of the Kaohsiung Medical University (IACUC-113029).

Data availability

All submitted sequences of Taiwan specimens can be accessed from the GenBank after publication.

Funding

This work was supported in part by grants from a cooperative project between Kaohsiung Medical University and National Pingtung University of Science and Technology (NPUST-KMU-113-P001), and from the National Science and Technology Council (NSTC113-2320-B-037-010), Taiwan, Republic of China.

Declaration of competing interest

The authors declare no competing interest.

Acknowledgement

We would like to express our sincere appreciation for the veterinary practitioners of National Pingtung University of Science and Technology, Pingtung, Taiwan, for their help in the collection of ticks for this study.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Data Availability Statement

All submitted sequences of Taiwan specimens can be accessed from the GenBank after publication.

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