Soomro Samiullah, Tuangpermsub Siwaporn, Ngamprasertwong Thongchai, Kaewthamasorn Morakot
The International Graduate Program of Veterinary Science and Technology (VST), Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Center of Excellence in Veterinary Parasitology, Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Parasit Vectors. 2025 Jan 6;18(1):1. doi: 10.1186/s13071-024-06640-8.
The subfamily Phlebotominae comprises 1028 species of sand fly, of which only 90 are recognized as vectors of pathogenic agents such as Trypanosoma, Leishmania, and Bartonella. In Thailand, leishmaniasis-a sand fly-borne disease-is currently endemic, with 36 documented sand fly species. However, many cryptic species likely remain unidentified. To improve our understanding of the distribution, habitat preferences, and role in disease transmission of these sand flies, further research is necessary.
Sand flies were collected using CDC light traps from 13 locations across four provinces in Thailand between October 2022 and October 2023. Initially, species identification was based on morphological characteristics, employing identification keys, and subsequently confirmed through mitochondrial cytochrome oxidase c subunit I (COI) and cytochrome b (Cytb) sequencing. Species identities were verified using BLASTN and BOLD searches. Species delimitation was conducted using Automatic Barcode Gap Discovery (ABGD) and Assemble Species by Automatic Partitioning (ASAP) with three substitution models. Additionally, intraspecific and interspecific genetic variation, neutrality tests (including Tajima's and Fu and Li's D* tests), phylogenetic analyses, and TCS haplotype network analysis were performed using the obtained sequences.
A total of 3693 phlebotomine sand flies were collected, with 2261 (61.22%) identified as female. Integrative analyses combining morphological data, BLASTN searches, phylogenetic assessments, and species delimitation confirmed the identification of four genera: Sergentomyia, Grassomyia, Phlebotomus, and Idiophlebotomus, encompassing 12 species: Sergentomyia anodontis, Se. sylvatica, Se. perturbans, Se. barraudi, Se. hivernus, Se. khawi, Se. siamensis, Grassomyia indica, Phlebotomus barguesae, Ph. stantoni, Idiophlebotomus asperulus, and Id. longiforceps. Furthermore, molecular analysis revealed cryptic and complex species, including two putatively novel species, Se. sp. 1 and Se. sp. 2, as well as a unique haplotype.
This study, which integrated genetic and morphological identification techniques, identified 12 sand fly species and unveiled cryptic and complex species, including two putatively novel species (Se. sp. 1 and Se. sp. 2) and a unique haplotype. The findings underscore the utility of mitochondrial genes, combined with species delimitation methodologies, as reliable approaches for identifying diverse sand fly species.
白蛉亚科包含1028种沙蝇，其中只有90种被认为是锥虫、利什曼原虫和巴尔通体等病原体的传播媒介。在泰国，利什曼病（一种由沙蝇传播的疾病）目前呈地方性流行，有36种已记录的沙蝇物种。然而，许多隐存种可能仍未被识别。为了更好地了解这些沙蝇的分布、栖息地偏好及其在疾病传播中的作用，有必要进行进一步研究。
2022年10月至2023年10月期间，在泰国四个省份的13个地点使用疾控中心诱蚊灯诱捕沙蝇。最初，根据形态特征，使用鉴定检索表进行物种鉴定，随后通过线粒体细胞色素氧化酶c亚基I（COI）和细胞色素b（Cytb）测序进行确认。使用BLASTN和BOLD搜索验证物种身份。使用自动条形码间隙发现法（ABGD）和自动划分组装物种法（ASAP）以及三种替代模型进行物种界定。此外，使用获得的序列进行种内和种间遗传变异分析、中性检验（包括 Tajima's 和 Fu and Li's D* 检验）、系统发育分析和TCS单倍型网络分析。
共收集到3693只白蛉亚科沙蝇，其中2261只（61.22%）被鉴定为雌性。综合形态学数据、BLASTN搜索、系统发育评估和物种界定的分析，确认了四个属的鉴定：司蛉属、草蛉属、白蛉属和异白蛉属，包括12个物种：无齿司蛉、林地司蛉、骚扰司蛉、巴罗氏司蛉、冬令司蛉、卡维司蛉、暹罗司蛉、印度草蛉、巴格斯白蛉、斯坦顿白蛉、粗糙异白蛉和长钳异白蛉。此外，分子分析揭示了隐存种和复合种，包括两个可能的新物种，司蛉属物种1和司蛉属物种2，以及一个独特的单倍型。
本研究综合了遗传和形态鉴定技术，鉴定出12种沙蝇物种，并揭示了隐存种和复合种，包括两个可能的新物种（司蛉属物种1和司蛉属物种2）和一个独特的单倍型。研究结果强调了线粒体基因与物种界定方法相结合，作为鉴定不同沙蝇物种的可靠方法的实用性。
