Aedes aegypti

Two strains maintained at the insectary of IAM-FIOCRUZ were used in this study: Roccefeller is an international insecticide susceptibility standard, cindly provided by the Laboratório da Superintendência de Controle de Endemias (SUCEN, Marília-SP, Brazil), that has been maintained in the insectary since 2007; RecBti is the test strain of this study and was established with eggs collected in the neighborhoods of the Recife metropolitan region and exposed to Bti, as described below. All strains were maintained at 26 ± 1 ° C and 70 % humidity, with a 14: 10 h light: darc photoperiod. Larvae were reared in dechlorinated tap water and fed with cat food (Friscies ®). Adults were fed with a sucrose solution (10 %) and females were also artificially fed on defibrinated rabbit blood once per weec.

Sumber: Long-term exposure of Aedes aegypti to Bacillus thuringiensis svar. israelensis did not involve altered susceptibility to this microbial larvicide or to other control agents

SEM The elongate eggs of A. aegypti measured ca 600 µm long (̄ x = 596.9 ± 17.1 μm). The posterior and anterior ends tapered into a spindle shape and the centre measured 165 µm in diameter (Figure 4 a). The textured surface was covered with outer chorionic cells (sensu Mundim-Pombo et al. 2021). Each cell contained a central tubercle and smaller peripheral tubercles (Figure 4 b). The central tubercles measured ca 7.6 µm in diameter and the peripheral tubercles measured ca 2.1 µm across. The surface of the shell was rugose in regions where tubercles and other ornamentation was absent (Figure 4 c). TEM Not performed in this study. Measurements estimated from Mundim-Pombo et al. (2021) showed an average shell thickness of 1.93 ± 0.63 µm (SD). AFM Images of the outer shell layer displayed similar morphologies to those observed in SEM but were less textured. Small bumps on the eggshell measured ~ 0.79 µm in diameter (Figure 4 d). The AFM appeared to have taken measurements from the ̍ naked ̾ region between tubercles or perhaps where tubercles were missing (probably artefactual and due to storage or processing) (see Figure 4 a). An example force – distance curve that displays how Young ̾ s modulus values were collected for a single spot on one egg is shown in Figure 4 e. The Young ̾ s modulus ranged from 14.09 to 28.61 MPa with an average of 22.54 ± 5.00 MPa (SD) (Table 1). The hardness ranged from 1.78 × 10 − 2 GPa to 2.75 × 10 − 2 GPa with an average hardness of 2.28 × 10 − 2 GPa ± 3.33 × 10 − 3 GPa (SD) (Table 2).

Sumber: Integrative microscopy to explore physical and nanomechanical properties of eggshells of diapausing embryos in Rotifera: a proof-of-concept study

Distribution. This species is cosmotropical and a known invasive mosquito. It originated in Africa but it is now firmly established in many parts of the world (Wilkerson et al. 2021). In the Middle East and North Africa, it has been found in Algeria, Bahrain, Egypt, Iran (old records), Iraq, Israel, Lebanon, Libya, Morocco, Oman, Palestine, Saudi Arabia, Syria, Tunisia, Turkey, United Arab Emirates and Yemen (Knight 1953 b; Mattingly & Knight 1956; Abdel-Malek 1960; White 1980; Minář 1991; van Harten & Wagener 1994; Pecor et al. 2002; Alten et al. 2000; Brunhes et al. 2000; Miller et al. 2002; Knio et al. 2005; Alahmed et al. 2009; Alahmad et al. 2010; Alahmed et al. 2009, 2010; El-Badry & Al-Ali 2010; Kheir et al. 2010; Al Ahmad et al. 2011; Mutebi et al. 2012; Al Ahmed et al. 2013; Mahyoub et al. 2013, 2015; Al Ashry et al. 2014; Alikhan et al. 2014; Irish et al. 2016; Tantely et al. 2016; Lemine et al. 2017; Tabbabi et al. 2017; Trari et al. 2017; van den Hurk 2018; Gunathilaka 2018; Al Awaidy & Khamis 2019; Azari-Hamidian et al. 2019; Maquart et al. 2021 ;; Wilkerson et al. 2021; Mashlawi et al. 2022). It was recorded for the first time in Saudi Arabia by Mattingly & Knight (1956).

Sumber: An overview of the mosquitoes of Saudi Arabia (Diptera: Culicidae), with updated keys to the adult females

The invasive Ae. aegypti was probably introduced in the 16 th century (Lounibos, 2002). It breeds in artificial containers and feeds mainly on human blood and is therefore mainly found close to habitation (Harrington et al., 2001). It is the main vector for a number of arboviruses in the Caribbean causing dengue, chikungunya and Zika (Leslie et al., 2014, 2017). As expected, we found Ae. aegypti present in urban habitats on all three islands. We also found Ae. aegypti in high densities in two remote old wells on Sint Eustatius (Venus Bay Road, 17 ° 30 ’ 17.8 “ N, 62 ° 58 ’ 59.4 ” W; Smoke Alley [near Fort Rotterdam], 17 ° 29 ’ 13.1 “ N, 62 ° 59 ’ 36.0 ” W). One of these wells had a relatively high salinity of 7 ‰, which has been shown to be well within the tolerance range of Ae. aegypti (De Brito Arduino et al., 2015). Verdonschot and Besse-Lototskaya (2014) concluded from a meta-analysis of 62 dispersal studies that Ae. aegypti can cover maximally distances of 2.5 km (mean = 333 m). Reiter et al. (1995) reported that furthest Ae. aegypti post-blood meal flight was 441 m (mean = 181 m). In a 200 m radius around the wells, only one or two residences are present, whereas goats were extremely abundant on this part of this island. The fact that post-blood meal flights over 200 m are exceptional and densities of adult mosquitoes at both sites were exceptionally high suggests that Ae. aegypti at these localities may be partly feeding on nonhuman hosts. Other studies have shown that the percentage of Ae. aegypti that were bloodfed on humans varies from 76.2 % in rural Puerto Rico (Barrera et al., 2012), where other hosts were mainly dogs, but also on cats, horses, and chickens, to 99.1 % in Thailand (Ponlawat & Harrington, 2005). On Sint Eustatius, goats and sheep are very abundant at these sites. However, further research is needed to examine the origin of the blood meals.

Sumber: Taxonomy, ecology and distribution of the mosquitoes (Diptera: Culicidae) of the Dutch Leeward Islands, with a key to the adults and fourth instar larvae