To overcome the difficulties of morphological and molecular identification of arthropods, MALDI-TOF MS has been proposed as an alternative identification technology to these two methods. However, the molecular identification approach is still limited by the high cost of reagents, the time consumed, and the absence of universal primers allowing for the amplification of a given gene in all species and sequences of all species on GenBank 20. Identification based on molecular amplification and sequencing of genes such as mitochondrial cytochrome oxidase subunits I and II (cox1 and cox2), genes coding for the NADH-ubiquinone oxidoreductase chain 1 ( ND1), Internal Transcribed Spacer (ITS2), large and small ribosomal RNA subunits ( 16S and 12S rRNA), and nuclear DNA such as 18S, Microsat and genes for endo-beta-1,4-glucanase ( RsEG),interactive domain-containing protein 1A ( AT-rich DNA) these molecular markers have proven to be an efficient alternative for species identification and overcoming morphological limitations 19. Morphological identification of termites, based mainly on the observation of morphological characteristics, is limited by the need for entomological expertise i.e., the difficulty in identification up to the species level due to the ambiguity of their features, crypto-biotic social structure and their similarity, the availability of identification keys and the long time required for identification. They participate in the beneficial chemical variation of the earth and its components 18. Termites can be used as bait to catch fish and birds 15 and as a natural human food resource that has a significant value in protein and vitamins 17. Termite species such as Macrotermes bellicosus have been shown to have anti-inflammatory and analgesic effects 16. They are also of interest in traditional medicine, particularly for suturing wounds and treating angina, fever, burns and abscesses 15. At the same time, they are known as ecosystem engineers by influencing the distribution of natural resources, such as water and nutrients in the ecosystem 11, and that refers to their ability to generate valuable biogenesis that improves soil properties 12, which increases water infiltration rates 13, 14. Termites attack the wooden parts of buildings and construction, causing damage costing more than three billion dollars each year, as well as in the agriculture field by eating fast-growing plants 9, 10. Many termite species are recognized as harmful. Humans and termites live in close proximity 8. Termites live in colonies divided into two castes (reproductive or sexual and sterile or asexual) 6, 7. Their distribution depends on climatic conditions, especially temperature and precipitation 5. Phylogenetic studies have indicated that the nearest relatives are cockroaches, which explains their classification in the order of Blattodea 4. They belong to the class Insecta, infra-order Isoptera 3. Termites or white ants belong to the arthropods that have thrived on earth for over 300 million years 1, 2. This study is the first on the use of MALDI-TOF for termite identification and shows its importance as a tool for arthropod taxonomy and reinforces the idea that MALDI-TOF MS is a promising tool in the field of entomology. Blind testing of the spectra of 389 termites against our updated database with the spectra of 43 specimens of different termite species revealed that all were correctly identified with log score values (LSVs) ranging from 1.65 to 2.851, mean 2.290 ± 0.225, median 2.299, and 98.4% (383) had LSVs > 1.8. Analysis of MALDI-TOF MS spectra profiles from termites revealed that all were of high quality, with intra-species reproducibility and inter-species specificity. Morphologically, 22 species were identified, including Ancistrotermes cavithorax, Amitermes evuncifer, Cryptotermes brevis, Cubitermes orthognathus, Kalotermes flavicollis, Macrotermes bellicosus, Macrotermes herus, Macrotermes ivorensis, Macrotermes subhyalinus, Microcerotermes parvus, Microtermes sp., Odontotermes latericius, Procubitermes sjostedti, Promirotermes holmgreni, Reticulitermes grassei, Reticulitermes lucifugus, Reticulitermes santonensis, Trinervitermes geminatus, Trinervitermes occidentalis, Trinervitermes togoensis, Trinervitermes sp., Trinervitermes trinervoides and Trinervitermes trinervius. A total of 432 termite specimens were collected in Mali, Cote d’Ivoire, Togo, Senegal, Switzerland and France. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) has proved effective for the identification of many arthropods.
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