Comparative molecular and morphological study of Stenoponia tripectinata tripectinata (Siphonaptera: Stenoponiidae) from the Canary Islands and Corsica

Differentiation of Synanthropic Fleas from Andalusia (Spain) through Geometric Morphometrics Analysis

Fleas (Siphonaptera) are ectoparasitic hematophagous insects responsible for causing bites and itchy skin conditions in both humans and animals. Furthermore, they can act as vectors of different pathogens of a wide variety of diseases worldwide, including bartonellosis, rickettsiosis, and bubonic plague. Accurate identification of fleas is necessary for the study of their epidemiology, prevention, and control. In addition to traditional morphological classification approaches and molecular biology techniques, geometric morphometrics is increasingly proving to be a useful complementary tool for discriminating between Siphonaptera taxa. With the objective of determining the capacity of this technique to identify and differentiate synanthropic fleas, a principal component analysis was carried out on populations of Ctenocephalides felis, Pulex irritans, and Archaeopsylla erinacei collected in distinct regions of Andalusia (Spain). The analysis carried out on 81 male and female specimens revealed factorial maps that allowed the differentiation of the populations under study, with only partial overlaps that did not prevent their correct identification. Global size differences were also detected, with a slightly larger size in P. irritans males and a bigger size in A. erinacei females. Therefore, the present study emphasizes the role of geometric morphometrics as a useful complementary technique in taxonomic studies of arthropods, especially in the case of flea specimens lacking representative morphological features.

New Insights into the Taxonomy of Malacopsylloidea Superfamily (Siphonaptera) Based on Morphological, Molecular and Phylogenetic Characterization of Phthiropsylla agenoris (Malacopsyllidae) and Polygenis (Polygenis) rimatus (Rhopalopsyllidae)

From a phylogenetic point of view, the Malacopsyllidae family and the Rhopalopsillidae family (comprising Parapsyllinae and Rhopalopsyllinae subfamilies) have been traditionally classified within the Malacopsylloidea superfamily, mostly restricted to South America. The phylogenetic relationships and taxonomic status of Malacopsyllidae and Rhopalopsillidae have never been assessed since no molecular loci of Malacopsyllidae have been sequenced by any authors, and the phylogeny provided so far was not based on any sort of formal quantitative analysis of flea morphology. Based on these precedents, the objective of this study was to carry out a comparative phylogenetic, molecular and morphological study of two different species belonging to each family, Phthiropsylla agenoris (Malacopsylla) and Polygenis (Polygenis) rimatus (Rhopalopsyllidae, Rhopalopsyllinae). In this study, we demonstrated the usefulness of several morphological features as diagnostic characters to differentiate between P. (P.) rimatus and P. agenoris. Using molecular and phylogenetic data, we easily discriminated between the two taxa (P. agenoris and P. (P.) rimatus) by comparing both nuclear and mitochondrial markers. This fact proves the usefulness of ITS2, EF1−α, cox1, cytb and cox2 as molecular diagnostic markers to characterize and identify different Siphonaptera taxa. Additionally, the phylogenetic results confirm, for the first time, the monophyly of the Malacopsyllidae family and suggest a clear paraphyletic position of the Paraspsyllinae subfamily and, consequently, the Rhopalopsyllidae family.

Morphometrics as a Complementary Tool in the Differentiation of Two Cosmopolitan Flea Species: Ctenocephalides felis and Ctenocephalides canis

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.