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The taxonomic status of the sand fly Phlebotomus (Euphlebotomus) argentipes Annandale & Brunette 1908, which transmits Leishmania (Leishmania) donovani (Laveran & Mesnil 1903) in southern Asia, is reassessed, because variation in morphology, behavior, and distribution suggests it to be a complex of sibling species. The putative complex is composed of the nominotypical member Phlebotomus argentipes sensu stricto, Phlebotomus annandalei Sinton 1923 status revived and Phlebotomus glaucus Mitra & Roy 1953 new status. An allolectotype is designated for the female of P. argentipes as well as neotypes for the males of P. annandalei and P. glaucus. Morphological descriptions, illustrations, and keys are presented to allow identification of adult males and females. Based on female morphological characters, P. argentipes s.s., P. annandalei and P. glaucus can be distinguished from each other using principal component analysis. P. glaucus is widespread in India, occurring sympatrically with P. argentipes s.s. in L. donovani-endemic foci, whereas P. annandeli is peripatric to the type species in Chennai, southern India. "In copula" is a process of postcopulatory sexual selection occurring as correlated coevolution of male and female reproductive traits, which drives species isolation. This pattern has been implicated in reproductive isolation among the members of the P. argentipes complex. Further research on adult behavior and larval biology of the P. argentipes complex is needed to understand the epidemiology and control of visceral leishmaniasis.

The morphology of insect genitalia is often highly species-specific, and its variation has been suggested as an important impetus for evolution. Structural variation of the male genitalia and the female spermathecae in Phlebotomine sand flies is unique among the blood sucking Diptera. We describe the fine structures involved in mating for Phlebotomus papatasi (Scopoli). Relationships among the length of the spermathecal duct and aedeagal filament were studied in 26 species of Old World phelebotomine sand flies comprising 12 subgenera. In most taxa the aedeagal filaments were very long allowing direct insemination into the spermathecae, indicating that intrasexual competition among males occurs as sperm precedence. There was a positive correlation between the lengths of the spermathecal ducts and aedeagal filaments, indicating that an evolutionary "arms race" occurs between males and females over the control of fertilization. The pattern of genitalia variation in phlebotomine sand flies also indicated that differences in the lengths of the spermathecal ducts and aedeagal filaments are distributed unevenly among closely related species. Genital differences do not seem to occur in populations of the Phlebotomus argentipes Annandale & Brunetti complex, whereas differences showed strongly in closely related Phlebotomus papatasi and P. bergeroti Parrot, and in sympatric Phlebotomus martini Parrot and P. celiae Minter.

A laboratory study was carried out to evaluate the repellent efficacy of a methanol-leaf extract of Ethiopian traditionally used insect repellent plant viz., Lomi sar [vernacular name (local native language, Amharic); Cymbopogon citratus (DC) Stapf. (Poaceae)] against Anopheles arabiensis at four different concentrations viz., 1.0, 1.5, 2.0, and 2.5 mg/cm(2). The percentage protection in relation to the dose method was performed. C. citratus extract has shown various degrees of repellency impact against A. arabiensis. It provided the maximum total percentage protection of 78.83% at 2.5 mg/cm(2) and followed 68.06% at 2.0 mg/cm(2) for 12 h. All four tested concentrations of C. citratus extract offered significant protection and Student's t test results shows statistically significant (p value = 0.001) [1.0 mg/cm(2) (t = 22.89; df = 4); 1.5 mg/cm(2) (t = 24.03; df = 4); 2.0 mg/cm(2) (t = 36.92; df = 4); 2.5 mg/cm(2) (t = 22.31; df = 4)] difference between treated and control groups. The result suggests that it could serve as a potent insect repellent against vectors of disease. Globally, C. citratus is renowned for its therapeutic values. Above and beyond, due to its user- as well as environmental-friendly nature, it should be promoted among the marginalized populations in order to reduce man-vector contact. In addition, this appropriate strategy affords the opportunity to minimize chemical repellent usage and the risks associated with adverse side effects. At the end of the day, traditionally used plant-based insect repellents could be viable safer alternative sources for chemical insect repellents.

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