Geometric morphometric wing analysis as a tool to discriminate female mosquitoes from different suburban areas of Chiang Mai province, Thailand

Abstract

Mosquitoes are hematophagous insects that transmit parasites and pathogens with devastating effects on humans, particularly in subtropical regions. Different mosquito species display various behaviors, breeding sites, and geographic distribution; however, they can be difficult to distinguish in the field due to morphological similarities between species and damage caused during trapping and transportation. Vector control methods for controlling mosquito-borne disease epidemics require an understanding of which vector species are present in the area as well as the epidemiological patterns of disease transmission. Although molecular techniques can accurately distinguish between mosquito species, they are costly and laborious, making them unsuitable for extensive use in the field. Thus, alternative techniques are required. Geometric morphometrics (GM) is a rapid and inexpensive technique that can be used to analyze the size, shape, and shape variation of individuals based on a range of traits. Here, we used GM to analyze the wings of 1,040 female mosquitoes from 12 different species in Thailand. The right wing of each specimen was removed, imaged microscopically, and digitized using 17 landmarks. Wing shape variation among genera and species was analyzed using canonical variate analysis (CVA), while discriminant function analysis was used to cross-validate classification reliability based on Mahalanobis distances. Phenetic relationships were constructed to illustrate the discrimination patterns for genera and species. CVA of the morphological variation among Aedes, Anopheles, Armigeres, Culex, and Mansonia mosquito genera revealed five clusters. In particular, we demonstrated a high percentage of correctly-distinguished samples among Aedes (97.48%), Armigeres (96.15%), Culex (90.07%), and Mansonia (91.67%), but not Anopheles (64.54%). Together, these findings suggest that wing landmark-based GM analysis is an efficient method for identifying mosquito species, particularly among the Aedes, Armigeres, Culex, and Mansonia genera.

Geometric morphometrics versus DNA barcoding for the identification of malaria vectors Anopheles dirus and An. baimaii in the Thai-Cambodia border

“…The highlights of the GM technique are that it is inexpensive, rapid, and does not require sophisticated equipment 31 . This technique has been used to distinguish members of groups of insects that are difficult to identify morphologically, such as horse flies (Tabanidae) 32 , stable flies (Muscidae) 33 , muscid flies (Muscidae) 34 , soldier castes (Rhinotermitidae) 35 , and mosquitoes (Culicidae) 30 , 36 , 37 . Recently, GM techniques were successful in identifying species members within malaria vector groups in Thailand, including the Maculatus group 38 and the Minimus complex 39 .…”

Species Identification of the Major Japanese Encephalitis Vectors within the Culex vishnui Subgroup (Diptera: Culicidae) in Thailand Using Geometric Morphometrics and DNA Barcoding

“…However, this method is prone to error, especially when identifying mosquitoes belonging to a species complex, as well as isomorphic species, cryptic species, and samples damaged during collection [ 12 ]. Therefore, several more advanced and accurate modern techniques have been used to identify mosquitoes, and these have greatly increased our knowledge and understanding of mosquito vectors [ 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. Culex pseudovishnui , Cx.…”

“…However, this method is limited by the need for complete morphological specimens and practitioner expertise [ 10 ]. Currently, effective alternative methods for species identification include geometric morphometrics and DNA barcoding; both may support the standard method to accurately identify mosquito samples that are morphologically similar [ 16 , 17 , 18 , 19 , 20 , 21 , 22 ].…”

Evaluating the significance of wing shapes in inferring phylogenetic proximity among the generic taxa: an example of Cantharinae (Coleoptera, Cantharidae)

“…In insects, the wing shapes of geometric morphometric analyses are usually applied in distinguishing the sibling species or uncovering the cryptic species (Baylac et al 2003;Pizzo et al 2006;Gurgel-Goncalves et al 2011;Muñoz-Muñoz et al 2011;Mitrovs ki-Bogdanović et al 2013), since that wing GM analysis represents a reliable and rapid alternative that yields satisfactory results when discriminating between morphologically analogous species (Champakaew et al 2021). Although the geometric morphometric data remains controversial in inferring the relationships among the organisms (Palci and Lee 2019), it has been applied in estimating the evolutionary relationships of some animals (Bogan and Roe 2008;Klingenberg 2015;Siriwut et al 2015;Püschel and Sellers 2016;Hart et al 2020;Goharimanesh et al 2022), especially in the higher grades (tribes or subfamilies or families) of some insect groups, based on the shapes of pronotum and elytra (Acevedo 2015;Eldred et al 2016;Zhang et al 2019;Tong et al 2021), as well as hind wings (Abou-Shaara and Al-Ghamdi 2012; Su et al 2015; Barour and Baylac 2016).…”

“…The GM method based on landmark data in inferring phylogenetic relationships among the generic taxa considering UPGMA, Maximum Parsimony and Neighbor-Joining as the optimality criterion (Champakaew et al 2021;Goloboff and Catalano 2016). In applying the GM method, we selected the cantharid beetles as the experimental subject.…”