Crustacean biodiversity as an important factor for mosquito larval control

Newly established ponds, which are highly dynamic systems with changing levels of biological interactions among species, are common larval mosquito habitats. We investigated the impact of crustacean abundance and taxa diversity on mosquito oviposition and larval development. The effects of the biological larvicide Bacillus thuringiensis israelensis (Bti) on mosquito larvae were monitored according to fluctuations in crustacean communities. Populations of the mosquito Culex pipiens colonized artificial ponds that contained crustacean communities at different time points of colonization by crustaceans: 1) ‘no colonization’ (no crustaceans), 2) ‘simultaneous colonization’ by crustaceans and mosquitoes, and 3) ‘head‐start colonization’ by crustaceans (preceding colonization by mosquitoes). All types of ponds were treated with three concentrations of Bti (10, 100, or 1,000 µg/liter). Colonization of all ponds by Cx. pipiens (in terms of oviposition, larval abundance, and larval development) decreased significantly with increasing diversity of crustacean taxa. The total abundance of crustaceans had a minor effect on colonization by Cx. pipiens. The presence of crustaceans increased the sensitivity of Cx. pipiens larvae to Bti treatment by a factor of 10 and delayed the time of recolonization. This effect of Bti was relevant in the short term. In the long term, the presence of Cx. pipiens was determined by crustacean biodiversity.     

Temporal and spatial habitat preferences and biotic interactions between mosquito larvae and antagonistic crustaceans in the field

Investigations on natural antagonists of mosquito larvae found that micro‐crustaceans (e.g., Cladocera) control mosquito populations under experimental conditions. However, their relevance for mosquito control under field situations remains widely unclear because important information about habitat preferences and time of occurrence of crustaceans and mosquito larvae are still missing. In order to fill this knowledge gap, a field study was undertaken in different wetland areas of Saxony, Germany, in different habitats (i.e., grassland, forest, and reed‐covered wetlands). We found negative interactions between larvae of Ae. vexans and predatory Cyclopoida (Crustacean: Copepoda), which both were dominant during the first two weeks of hydroperiod, at ponds located at grassland habitats. Larvae of Cx. pipiens were spatially associated with competing Cladocera, but they colonized ponds more rapidly. Populations of Cladocera established from the third week of hydroperiod and prevented Cx. pipiens colonization thereafter. Ostracoda were highly abundant during the whole hydroperiod, but their presence was restricted to habitats of reed‐covered wetland at one geographical area. Mosquito larvae hardly occurred at those ponds. In general, we found that ponds at the reed‐covered wetlands provided better conditions for the initial development of crustaceans and hence, mosquito larval colonization was strongly inhibited. Grassland habitat, in contrast, favored early development of mosquito larvae. This study showed that micro‐crustaceans are relevant for mosquito management but their impact on mosquito larvae varies between species and depends on environmental conditions.     

Insecticidal effects of a novel polyherbal formulation (HF7) against Culex pipiens L. (Diptera: Culicidae)

Plant secondary metabolites represent the most efficient and convenient method to control and overcome environmental pollution and insecticidal resistance. This study explored the mosquitocidal activity of the combined extract of seven plants, (HF7) extracted using a Soxhlet extractor against Culex pipiens under laboratory conditions. Exposure of the 3rd instars of Cx. pipiens to HF7 hexane extract resulted in LC₅₀:114.5 μg/mL and LC₉₀:117.0 μg/mL values after 24 h. The ovicidal activities of hexane extract against Cx. pipiens eggs were 21.6%, 48.3%, and 71.6% at 187.5, 93.7, and 46.88 μg/mL, respectively. HF7-treated larvae showed the formation of irregular blebbing of epithelial cells toward the lumen and sloughing into the gut lumen. HF7 extract resulted in 100% adulticidal mortality at the concentration of 3.7 mg/test tube after 30 min of exposure. The IC₅₀ of HF7 extract was 97.03 µg/ml against larvae, at which nuclear and morphological changes were observed. The spectroscopy spectrum of HF7 hexane extract disclosed the presence of 57 different secondary metabolites, among which the dominant compound was eugenol (32.3%). HF7 hexane extract could serve as a botanical insecticide for controlling Cx. pipiens and potentially other mosquito species.     

Larvicidal activity of some fungal extracts on Aedes caspius and Culex pipiens (Diptera: Culicidae)

A preliminary study was conducted to evaluate the effects of nine methanol fungal extracts on fourth instar larvae of Aedes caspius and Culex pipiens (Diptera: Culicidae). None of the extracts tested showed larvicidal activity except for the Paecilomyces lilacinus extract, which showed 100 % mortality against the larvae of Ae caspius after 24 h. The LC₅₀ values of the P. lilacinus extract after 24 h were 190.66 μg/mL against Ae. caspius and 254.25 μg/mL against Cx. pipiens, respectively. After 48 h, meanwhile, the LC₅₀ values were 65.70 and 164.13 μg/mL, respectively. Histological analysis of the midgut of the treated larvae of Ae. caspius and Cx. pipiens revealed changes such as cell destruction, spacing between the cells and disruption of the microvilli, resulting in an appearance of vacuolization in the midgut. This article is the first report of the use of P. lilacinus extract for the control of Ae. caspius and Cx. pipiens larvae and the data obtained may help to provide a better understanding of the mode of action of P. lilacinus as an insecticide against mosquito larvae.     

Larvicidal activity and Histopathological changes of Cinnamomum burmannii,Syzygium aromaticum extracts and their combination on Culex pipiens

In order to develop an eco-friendly botanical larvicide alternative to the synthetic larvicides, extracts were prepared from the Cinnamomum burmannii (C.B.) and Syzygium aromaticum (S.A.) with hexane using a sonicator. The extracts were evaluated for larvicidal activity individually and in combination against the Culex pipiens larvae. The LC₅₀ value of C.B. and the S.A. hexane extracts tested individually were 184.2 and 363.7 µg/mL against Cx. pipiens respectively. All the combinations of the extract of C.B. and S.A. showed synergistic factors higher than one. Among the different ratios of extracts, the SA25%: CB75% extract was found to be more toxic than the other combinations (LC₅₀:125.7 µg/mL). Midgut cells treated with S.A. 25%: C.B. 75% extract showed severe morphological alterations such as degradation of microvilli; degeneration of epithelial cells, and peritrophic membrane; loss of nuclei, irregular and damage of microvilli. The extract has a promising larvicidal potential against Cx. pipiens, However, the extract was toxic against HUVEC cells, as evident from MTT and cell morphology. Further investigation is required to assess the toxicity of the extract on aquatic animals.     

Chilodonella uncinata is Not Pathogenic to Culex pipiens Mosquitoes

Chilodonella uncinata was previously reported to be pathogenic to Culex and other mosquitoes based on the observation of high densities of ciliates inside of dead mosquito larvae. Here, we tested whether co‐culturing Cx. pipiens with Ch. uncinata resulted in decreased survival of the mosquito larvae. We find no evidence that Ch. uncinata is pathogenic to Cx. pipiens. We suggest that Ch. uncinata may instead feed on already deceased larvae.     

Effects of nutrition and density in Culex pipiens

Mosquito larvae face numerous biotic and abiotic challenges that affect their development and survivorship, as well as adult fitness. We conducted two experiments under semi‐natural conditions to evaluate the effects of intraspecific competition, nutrient limitation and sub‐lethal doses of malathion on individual life history traits in adult Culex pipiens (Diptera: Culicidae). In the first experiment, larvae of Cx. pipiens were reared at different intraspecific densities and exposed to sub‐lethal doses of malathion. In the second experiment, different intraspecific densities of Cx. pipiens larvae were reared under conditions of low or high larval nutrients, and subsequent adults were fed on either water or 10% sucrose solution. Malathion treatment had relatively minor effects compared with density, which had significant negative effects on development rate, survivorship to adulthood, body size (wing length) and longevity. As larval density increased, a sex ratio distortion in survivorship to adulthood emerged, in which a bias towards males was apparent. Nutrient‐rich larval environments alleviated, in part, the effects of increasing density and extended the lifespan of mosquitoes fed on water and 10% sucrose. Density‐dependent alterations in adult longevity attributable to the larval environment are complex and show contrasting results depending on interactions with other environmental factors. This study suggests that larval resource availability and competition influence Cx. pipiens population growth correlates and have lasting effects on traits that relate to a mosquito's ability to vector pathogens.     

Larvicidal,ovicidal activities and histopathological alterations induced by Carum copticum (Apiaceae) extract against Culex pipiens (Diptera: Culicidae)

An experiment was carried out, firstly, to determine the possible toxicity of Carum copticum (Apiaceae) extract against Culex pipiens (Diptera: Culicidae), and, secondly, to study the histopathological alterations in the midgut of Cx. pipiens as a result of treatment with C. copticum extract. Larvicidal and ovicidal activities of C. copticum extract against the larvae of Cx. pipiens was determined according to World health organization (WHO). The inhibition effect of C. copticum was assessed by determining the mortality of the treated larvae and eggs. The histopathological effect of the C. copticum extracts on midgut epithelium of the larvae was examined under both light and transmission electron microscopy. The crude extract of C. copticum exerted 100% mortality for Cx. pipiens after 24 h at 200 μm/ml, and zero hatchability (100% mortality) at 150 μm/ml for Cx. pipiens. The histopathological study showed that larvae treated with C. copticum extract had cytopathological alterations of the midgut epithelium. The study provided information on various effects of C. copticum extract against Cx. pipiens.     

The arbovirus vector Culex torrentium is more prevalent than Culex pipiens in northern and central Europe

Two species of arbovirus vector, Culex torrentium and Culex pipiens (Diptera: Culicidae), occur in several European countries, but difficulties in their accurate identification and discrimination have hampered both detailed and large‐scale distribution and abundance studies. Using a molecular identification method, we identified to species 2559 larvae of Cx. pipiens/torrentium collected from 138 sites in 13 European countries ranging from Scandinavia to the Mediterranean coast. In addition, samples of 1712 males of Cx. pipiens/torrentium collected at several sites in the Czech Republic were identified to species based on the morphology of their hypopygia. We found that the two species occur together in large areas of Europe, and that Cx. torrentium dominates in northern Europe and Cx. pipiens dominates south of the Alps. The transition in dominance occurs in central Europe, where both species are roughly equally common. There was a strong correlation between the length of the growing season at different sites and occurrences of the two species. As the growing season increases, the proportion and detection of Cx. torrentium decrease, whereas those of Cx. pipiens increase. The present findings have important consequences for the interpretation of the results of studies on major enzootic and link‐vectors of mosquito‐borne bird‐associated viruses (i.e. Sindbis, West Nile and Usutu viruses), especially in central Europe and Scandinavia.     

The mosquito fauna of the western region of Spain with emphasis on ecological factors and the characterization of Culex pipiens forms

This study updates the diversity, distribution, and seasonal trends of mosquitoes in a western region of Spain, assesses ecological determinants of Culex pipiens s.l., and determines form composition of Cx. pipiens s.s. populations. A total of 1,495 mosquitoes of 16 species was collected during 2012–2013, of which Cx. pipiens s.l. and Cx. theileri were the most abundant. Five new records for An. maculipennis s.s., Orthopodomyia pulcripalpis, Aedes (Ochlerotatus) punctor, Cx. europaeus, and Cx. modestus were found for this region. Cx. pipiens density varied across weather and habitat patterns, correlating positively with high temperatures and with a preference for urbanized areas and rural areas within a proximity of ovine farms. Moreover, molecular identification by CQ11FL was performed in 467 Cx. pipiens s.s., detecting both pipiens (66%) and molestus (8.4%) forms coexisting in different habitats (urban, peri‐urban and rural) aboveground with a high degree of hybridization (25.7%). The abundance of Cx. pipiens in urban areas and farms, with the presence of hybrids, may increase their capacity to act as bridge vectors for the transmission of arboviral infections. These data will be helpful for further implementation of entomological programs focused on risk assessment for arboviruses or other mosquito‐borne pathogens.     

The effect of shade on the container index and pupal productivity of the mosquitoes Aedes aegypti and Culex pipiens breeding in artificial containers

Abstract The aim of this study was to assess whether certain attributes of larval breeding sites are correlated with pupal productivity (i.e. numbers of pupae collected per sampling period), so that these could be used as the focus for control measures to enhance control efficiency. Therefore, the objectives were to identify the months of highest pupal productivity of Aedes aegypti (L.) and Culex pipiens L. (Diptera: Culicidae) in an urban temperate cemetery in Argentina where artificial containers of < 6 L (flower vases) were the predominant breeding habitats, to compare various measures of the productivity of sunlit and shaded containers and to determine whether the composition of the containers affected pupal productivity. Over a period of 9 months, 200 randomly chosen water‐filled containers (100 sunlit and 100 shaded), out of ～ 3738 containers present (～ 54% in shade), were examined each month within a cemetery (5 ha) in Buenos Aires (October 2006 to June 2007). In total, 3440 immatures of Cx pipiens and 1974 of Ae. aegypti were collected. The larvae : pupae ratio was 10 times greater for the former, indicating that larval mortality was greater for Cx pipiens. Both mosquito species showed a higher container index (CI) in shaded than in sunlit containers (Ae. aegypti: 12.8% vs. 6.9% [χ² = 17.6, P < 0.001]; Cx pipiens: 6.3% vs. 1.8% [χ² = 24, P < 0.001]). However, the number and the density of immatures per infested container and the number of pupae per pupa‐positive container did not differ significantly between sunlit and shaded containers for either species. Therefore, the overall relative productivity of pupae per ha of Ae. aegypti and Cx pipiens was 2.3 and 1.8 times greater, respectively, in shaded than in sunlit areas as a result of the greater CIs of containers in shaded areas. Neither the CI nor the number of immatures per infested container differed significantly among container types of different materials in either lighting condition. The maximum CI and total pupal counts occurred in March for Ae. aegypti and in January and February for Cx pipiens. The estimated peak abundance of pupae in the whole cemetery reached a total of ～ 4388 in the middle of March for Ae. aegypti and ～ 1059 in the middle of January for Cx pipiens. Spearman’s correlations between monthly total productivity and monthly CI were significant at P < 0.001 for Ae. aegypti (r_s = 0.975) and P < 0.01 for Cx pipiens (r_s = 0.869). Our findings indicate that the efficacy of control campaigns against the two most important mosquito vectors in temperate Argentina could be improved by targeting containers in shaded areas, with maximum effort during species‐specific times of year when pupal productivity is at its peak.     

Larvicidal potency of selected xerophytic plant extracts on Culex pipiens (Diptera: Culicidae)

Chemical insecticides released into the environment may have adverse biological effects. Therefore, there is a need for ecofriendly insecticides for mosquito control. Xerophytic plant extracts that may provide more ecofriendly active component were evaluated against Culex pipiens 4th instars. Plant extracts prepared using different solvents with a Soxhlet apparatus and different concentrations were tested against Culex pipiens larvae. The effects were observed at 24 h and 72 h intervals and LD₅₀ and LD₉₀ values determined. Chloroform (CHCl₃) and ethyl acetate (EtOAc) extracts of Althaea ludwigii were the most effective against Cx. pipiens 4^th instars, but were highly dependent on extract concentrations and exposure time. Results suggest that A. ludwigii extracts contain bioactive compounds, such as phenols and saponins, that may provide effective Cx. pipiens larval control. However, the extract was found to be toxic to zebrafish larvae, and may be toxic to other aquatic fauna. Further studies to determine the active components and toxicity to other fauna are needed.     

A rural–urban latitudinal study of the distributions of Culex quinquefasciatus and Culex pipiens bioforms in their southernmost sympatric fringe

Mosquitoes grouped in the complex Culex pipiens L. (Diptera: Culicidae) are important vectors of medical and veterinary diseases. In the South American sympatric region, Cx. pipiens and Culex quinquefasciatus Say coexist and potentially hybridize. To identify key drivers of their geographical distribution, mosquito immatures were collected from flower vases of eight urban/rural cemetery pairs within a 5° latitudinal transect along Buenos Aires Province, Argentina. The specimens were identified by molecular methods and their relative proportion modelled as a function of environmental variables. At the beginning of the warm season, northern and southern cemeteries presented exclusively Cx. quinquefasciatus and Cx. pipiens, respectively, with different proportions of both at mid latitudes. By the end of the summer, Cx. quinquefasciatus was present throughout the study area, exclusively in 11 of the 16 cemeteries both rural and urban, whereas Cx. pipiens was predominant only in the southernmost pair. Mean annual temperature, photoperiod variability and time of the season were key drivers of their distributions. All specimens of Cx. pipiens were identified as form molestus and no hybrids were recognized. The reported distribution patterns and the potential absence of Cx. pipiens f. pipiens and hybrids are discussed, along with their implications in disease transmission.     

Distribution and ecology of mosquitoes in a focus of dirofilariasis in northwestern Iran, with the first finding of filarial larvae in naturally infected local mosquitoes

A study of the distribution and ecology of mosquitoes (Diptera: Culicidae) in Ardebil Province of northwestern Iran, with special reference to the known dirofilariasis focus in Meshkinshahr County, was carried out in July‐August 2005 and April‐October 2006. In total, 17 533 adult mosquitoes and 3090 third‐ and fourth‐instar larvae were collected on 14 occasions and identified using morphological characters and DNA sequence data. Twenty species belonging to seven genera were found: Anopheles claviger (Meigen), An. hyrcanus (Pallas), An. maculipennis Meigen, An. pseudopictus Grassi*, An. sacharovi Favre, An. superpictus Grassi, Aedes vexans (Meigen)*, Coquillettidia richiardii (Ficalbi)*, Culex hortensis Ficalbi, Cx. modestus Ficalbi, Cx. pipiens Linnaeus, Cx. theileri Theobald, Cx. torrentium Martini*, Cx. tritaeniorhynchus Giles, Culiseta longiareolata (Macquart), Cs. annulata (Schrank)*, Cs. subochrea (Edwards), Ochlerotatus caspius (Pallas) s.l.* (= Aedes caspius sensu auctorum), Oc. geniculatus (Olivier)* (= Aedes geniculatus sensu auctorum) and Uranotaenia unguiculata Edwards (asterisks indicate new occurrence records for the province). The most prevalent species in adult catches were An. maculipennis (52%), Cx. theileri (45%) and Cx. hortensis (1%); the most prevalent species caught as larvae were Cx. theileri (27%), Cx. hortensis (21%) and An. maculipennis (19%). Anopheles maculipennis, Cx. pipiens and Cx. theileri were most widely distributed in the province. The occurrence of Cx. torrentium in Iran is verified based on differential characters of fourth‐instar larvae. Anopheles maculipennis and An. sacharovi of the Maculipennis Group were identified from their diagnostic ITS2 sequences. For the first time, cytochrome c oxidase I (COI) sequences were obtained from Iranian specimens of An. hyrcanus, An. pseudopictus, Cx. theileri and Oc. caspiuss.l. Culex theileri and An. maculipennis were found naturally infected with third‐stage (infective) larvae of Dirofilaria immitis (Leidy) and Setaria labiatopapillosa (Alessandrini) (Spirurida: Onchocercidae), respectively, for the first time in Iran.     

Sympatric occurrence of Culex pipiens (Diptera,Culicidae) biotypes pipiens,molestus and their hybrids in Portugal,Western Europe: feeding patterns and habitat determinants

Culex (Culex) pipiens (Diptera: Culicidae) has two recognized biotypes, pipiens and molestus, which differ in physiology and behaviour; this difference may influence vectorial capacity for West Nile virus (WNV). Our goal was first to determine the presence of Cx. pipiens populations in 31 locations in Portugal and to subsequently analyse their host‐feeding preferences and habitat determinants. Molecular identification of Cx. pipiens forms and their hybrids was performed in 97 females; bloodmeal sources were identified in 59 engorged specimens. Overall, 61.9% of specimens were identified as Cx. pipiens f. pipiens, 20.6% as Cx. pipiens f. molestus, and 17.5% as hybrid forms. Culex pipiens f. pipiens fed preferentially on birds, and Cx. pipiens f. molestus on humans. Hybrid forms fed mostly on birds, but human bloodmeals were common. With reference to habitat, Cx. pipiens f. pipiens and hybrid forms were positively correlated with peri‐urban habitats. Our results confirm the sympatric presence of different Cx. pipiens biotypes in 14 of the 31 locations studied. Peri‐urban areas were a common habitat of all biotypes and may represent zones of hybridization. The feeding preferences and sympatric distribution of the Cx. pipiens biotypes observed in Portugal favour the epizootic circulation of WNV and the occurrence of disease outbreaks of WNV.     

Vector competence of northern and southern European Culex pipiens pipiens mosquitoes for West Nile virus across a gradient of temperatures

In Europe, West Nile virus (WNV) outbreaks have been limited to southern and central European countries. However, competent mosquito vectors and susceptible bird hosts are present in northern Europe. Differences in temperature and vector competence of mosquito populations may explain the absence of WNV outbreaks in northern Europe. The aim of the present study was to directly compare vector competence of northern and southern European Culex pipiens (Cx. p.) pipiens mosquitoes for WNV across a gradient of temperatures. WNV infection and transmission rates were determined for two Cx. p. pipiens populations originating from The Netherlands and Italy, respectively. Mosquitoes were orally exposed by providing an infectious bloodmeal, or by injecting WNV (lineage 2) in the thorax, followed by 14‐day incubation at 18, 23, or 28 °C. No differences in infection or transmission rates were found between the Cx. p. pipiens populations with both infection methods, but WNV transmission rates were significantly higher at temperatures above 18 °C. The absence of WNV outbreaks in northern Europe cannot be explained by differences in vector competence between Cx. p. pipiens populations originating from northern and southern Europe. This study suggests that low temperature is a key limiting factor for WNV transmission.     

Culex pipiens affected by joint infection of a mosquito iridescent virus and Strelkovimermis spiculatus

Dual infections with a mosquito iridescent virus (MIV) and the mermithid nematode, Strelkovimermis spiculatus were recorded in natural Culex pipiens populations around La Plata city, Argentina. S. spiculatus was detected in 82% of samples that were positive for MIV infection. Dissected larvae of Cx. pipiens with patent MIV infection presented 42% infection with S. spiculatus. Larvae of Cx. pipiens exposed to MIV and S. spiculatus under laboratory conditions produced a high joint infection rate (82.5%) while no infection was recorded on larvae exposed to virus suspension only. Field and laboratory results suggest a strong association between S. spiculatus and MIV in natural populations of Cx. pipiens, in which S. spiculatus could be a mode of entry for the virus into the mosquito hemocele.     

New evidence for the potential role of Culex pipiens mosquitoes in the transmission cycle of West Nile virus in Tunisia

Physiological and molecular characteristics of natural populations of Culex pipiens Linnaeus, 1758 (Diptera: Culicidae) were investigated to elucidate how this species is potentially involved in the transmission of West Nile virus in Tunisia. A total of 215 Cx. pipiens females from 11 breeding habitats were analysed in the laboratory to estimate autogeny and stenogamy rates. They were tested individually for the locus CQ11 to distinguish between the two Cx. pipiens forms, pipiens and molestus. All tested Cx. pipiens populations were stenogamous. Females from underground breeding sites were all autogeneous, whereas females from above‐ground habitats were mostly anautogeneous. Of all the females tested, 59.7% were identified as pipiens, 22.4% as molestus, and 17.9% as hybrid pipiens/molestus. Furthermore, both Cx. pipiens forms and their hybrids were found to co‐occur in sympatry in all sites. The results of this study represent the first evidence that both Cx. pipiens forms and their hybrids are present in Tunisia. Because hybrids able to act as bridge vectors are present in all studied habitats, Tunisia can be considered to have a high degree of receptivity for the establishment of West Nile virus zoonotic cycles.     

Biosynthesis of gold and silver nanoparticles using Senna alexandrina Miller extract against Culex pipiens L. (Diptera: Culicidae)

The use of nanoparticles for various purposes, including pest control, has become increasingly popular because of their cost and environmental safety. In the present study, gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) were synthesized in an extract of Senna alexandrina Miller leaves with the aim of use against vectors of disease such as Culex pipiens L. (the filarial vector in Saudi Arabia). The nanoparticles were characterized by scanning electron microscopy and spectroscopic techniques. The larvicidal activity of the nanoparticles against Cx. pipiens was evaluated according to the protocol of the World Health Organization. According to the lethal concentration LC₅₀, the result shows differentiation in the sensitivity on mosquitoes. The AuNPs (51.383 ppm) the best one followed by AgNPs (52.525 ppm) while S. alexandrina leaf extract alone (355.25 ppm), the lowest effectiveness. Generally, the Cx. pipiens mosquito larvae proved to be more susceptible to AuNPs and AgNPs than leaf extract alone by about 6.91 and 6.76 times, respectively.     

Target and non-target effects of Foeniculum vulgare and Matricaria chamomilla combined extract on Culex pipiens mosquitoes

The present study focused on extracting green larvicides from extracts of the combination of Foeniculum vulgare and Matricaria chamomilla using different solvents of increasing polarity in a Soxhlet extractor and evaluating their ovicidal, larvicidal, and cytotoxic activities. The most promising among all tested extracts was hexane extract. The ovicidal activity of the hexane PH2 extract resulted in a significant (p < 0.05) decrease in egg hatchability from 95.00 ± 6.16% to 15 ± 9.04% at doses ranging from 62.5 to 500 µg/mL. The larval mortality with the hexane extract ranged from 13.33 ± 3.3% to 93.33 ± 3.3% at doses ranging from 31.25 to 250 µg/mL, respectively. The LC₅₀ and LC₉₀ values of the larvicidal activity of the hexane extract were estimated to be 148.3 and 242.17 µg/mL, respectively, after 24 h of exposure. Similarly, the LC₅₀ values after 48 and 72 h of exposure were 124.93 and 100.3 µg/mL, respectively, against the third instar of Cx. pipiens. PH2 treatment of larvae resulted in histopathological changes such as degenerated epithelial cells and destruction of microvilli on the epithelial cells. The PH2 extract achieved a dose-dependent decrease in the rate of cell survival. The IC₅₀ value of PH2-treated HUVECs was 192.07 µg/mL after 24 h of incubation. The cells showed changes in cellular and nuclear morphology. In conclusion, the hexane extract of PH2 could be used in mosquito management programs.