Fauna of mosquito larvae [diptera: culicida] in Asir provence, Kingdom of Saudi Arabia

An entomological survey was undertaken for one year to update the mosquito fauna of Asir Region, Kingdom of Saudi Arabia. A total of 31 species of 8 genera were reported of which genus Culex [55%] was the most common. Most of collected larvae [59%] belonged to genus Culex [+ Lutzid] followed by Culiseta [26%], Anopheles [13%] and Aedine spp.[2%]. Cx. pipiens [39%] and Cs. longiareolata [26.%] were generally the most abundant of all collected larvae. Of the Anopheles spp., An. dthali was common [40%], of Culex spp., Cx. pipiens was predominating [66%] and of Aedine spp., St. aegypti was predominating [71%]. Four species: An.fluviatilis, Cx. mattinglyi, Cx. arbieeni and Cx. mimeticus were new reports in Asir Region and Cx. wigglesworthi recorded for the first time from the kingdom. Larvae were more common in low- and highlands than in the moderately altitude areas. In general all species prefer stagnant water but with the exception of Aedine larvae [altogether], the other species prefer presence of algae, vegetation and shade and absence of turbidity [except Culex spp.]. A total of 98 different forms of association were reported of which 9 forms were common. All genera breed year round with peaks of abundance during spring for Anopheles spp. and Culex spp. and during winter for Aedine spp. and Cs. longiareolata. A Complete list of mosquito fauna of Asir Region comprising 45 spp. was presented based on the present and previous surveys. The study concluded that the occurrence and prevalence of friosquito species mainly the disease vectors in Asir carry the thread of maintaining and transmission of several mosquito-borne diseases

Population ecology of mosquitoes and the status of bancroftian filariasis in el Dakahlia governorate, the Nile Delta, Egypt

Mosquitoes were surveyed [Oct. 2010 and Apr. - Oct. 2011] in some localities representing 13 centers of El-Dakahlia Governorate. Six mosquito species were collected: Culex pipiens, Cx. antennatus, Cx. perexiguus, Ochlerotatus detritus, Anopheles pharoensis and An. tenebrosus. Culex pipiens was predominating [ca 79% larvae, 51% adults]. Culex antennatus and Cx. perexiguus were also common. Of the Four types of the breeding habitats, the drainage canals were the most productive [53.4% larvae]. For the three common species, the compiled larval density increases as water temp, increased and decreases as pH increased while adult indoor density increases as indoor and outdoor temp, and indoor RH increased and decreases as outdoor RH increased. Cx. pipiens significantly associated with Cx. antennatus [C[AB]=0.88 and I=0.48] while Cx. antennatus has a moderate association with Cx. perexiguus [C[AB]=0.47 and I=0.36]. Out of 908 examined blood samples from ten centers, 7.49% were infected with Wuchereria bancrofti. The highest infection rates in some centers were associated with high indoor densities of Cx. pipiens females, the main filariasis vector. The situation necessitates a wide vector control program to minimize lymphatic filariasis transmission in this Governorate

Mosquitoes [diptera: culicidae] in relation to the risk of disease transmission in el Ismailia Governorate, Egypt

Mosquito were surveyed [Nov. 2009 - March 2010] in El Ismailia Governorate. Nine species were reported: Culex pipiens, Cx. perexiguus, Cx. antennatus, Anopheles tenebrosus, An. pharoensis, An. multicolor, Ochlerotatus detritus, Oc. cas-pius and Culiseta longiareolata. Culex pipiens was the predominant species [ca. 87% larvae and 57% adults]. For the 3 common species, Cx. pipiens, Cx. perexiguus, and Cx. antennatus the following were examined: [1] the type and characteristics [temperature and pH] of the breeding habitats and their relation to the larval density and [2] the relation of adult indoor density to the indoor and outdoor temperature and RH. The abundance of mosquito vectors in El Ismailia with its old history of vector transmitted diseases contributes to the risk of mosquito borne disease transmission in this area. This would assist in the control activities

Geographical distribution and relative abundance of culicine mosquitoes in relation to transmission of lymphatic filariasis in El Menoufia Governorate, Egypt

Culicine mosquito were surveyed in El Menoufia Governorate [October to November 2008 and April to May 2009] in villages representing eight districts. Six species were reported: Culex [Culex] pipiens Linnaeus, Cx. [Cx] perexiguus Theobald, Cx. [Cx.] antennatus [Becker], Aedes [Ochlerotatus] caspius [Pallas], Aedes [Ochlerotatus] detritus [Haliday] and Culiseta [Allotheobaldia] longiareolata [Macquart]. Cx. pipiens, the main filariasis vector was the commonest or predominating species [ca. 47% adults and 92% larvae, P<0.01]. For the common species, the following were investigated: 1-temperature and pH of the breeding habitats and their relation to the larval density and 2-relation of adult indoor density with indoor-and outdoor-temperature and RH. Besides, parasitologically, Wuchereria bancrofti cases [33/631 blood samples, 5.23%] were detected in three districts [range=1.96-14.12% infection]. The cases were associated with the abundance of Cx. pipiens adults [ca. 45-62% of the collected adults]

Climatic factors influencing the abundance of Phle-botomus papatasi [Scopoli] [diptera: Psychodidae] in the Nile Delta

Ecological studies on sand flies were carried out in two villages of the Nile Delta Governorates namely; Kafr Tahla [Qalyubiya] and el Quantara el Beida [Kafr el-Sheikh] from September 2003 to August 2005. Sand flies were collected weekly from around houses, stables and near rodent burrows using sticky paper traps. A total of 9529 sand flies were collected from the two villages, all of which were identified as Phlebotomus papatasi. Sand fly activity started from April to December with a bimodal annual pattern. The sex ratio of collected sand flies was significantly male biased. Data analyses revealed that sand fly densities were strongly correlated to temperature but not to relative humidity or wind velocity. Variation in the densities of P. papatasi in both villages did not show a significant effect due to lunar phases. However, sand fly activity was highly positively correlated to fraction illumination

ecological characteristics of anopheles mosquitoes associated with low malaria transmission in Siwa Oasis, Egypt

The ecology of Anopheles sergentii and an multicolor was investigated over eight months to examine the entomological factors maintaining the low plasmodium vivax transmission in Siwa oasis. The two species were encountered as larva while the dominant species, Anopheles sergentii was also collected as adults. Breeding sites were characterized for the two species in six localities. Larvae of both species were common during June and November. In Bahi El Din as an indicator village with a higher endemicity, an sergentii females were endophilic but more common inside animal sheds than in houses, attracted more to donkey-baited traps than to human hosts, more endophagic as human biters and were more common in May/June and November. Female survivor hip was higher in November than in the other months. Vector potential of an sergentii was predicted and revealed that the species characteristics [low human contact, short survival and zoophilic feeding behaviour] are responsible for maintaining such low and unstable malaria in Siwa oasis

Comparison of the life table characteristics of anopheles sergentii [diptera: culicidae] from two malarious areas in Egypt

Life table characteristics were examined for the malaria vector, an sergentii from two Faiyum villages: Tersa [T] and El Nazlah [N] and from Siwa oasis [Sw] under constant laboratory conditions at 25°C and 70% RH. Females of T, N and Sw completed 4, 5, and 2 gonotrophic cycles [gc] respectively. The first gc required a significantly longer period [p < 0.05] than the subsequent ones. Development times for Sw immatures were longer [p < 0.05] than for the other colonies. Life expectancies at emergence for males of the 3 colonies were significantly shorter than for their respective females. Generation time was shorter [p < 0.05] for T [mean = 31.15 days] than for Sw [37.81 days] or N [43.64 days] colonies. The birth rate of Sw colony [mean 0.33 o+ o+/o+] was significantly higher [p < 0.05] than those of the other colonies. The other biological parameters: fecundity, egg hatch times and rates, survivorship from egg eclosion to adult emergence, male and survivorships, net reproductive rate, -intrinsic rate of increase all showed no colony variations. The study concluded that variation among colonies in certain biological aspects may not reflect strain differences

Fauna of anopheline mosquitoes [diptera: culicidae] in AR Egypt Historical background and present situation

Based on the available reports of the mosquito surveys carried out over eighty years starting from 1903, the author reviewed and updated the information on distribution and abundance of the anopheline mosquito fauna of Egypt. The present status of twelve reported species are discussed

Sandflies [diptera: psychodidae] in Mersa Matrouh and Siwa Oasis, AR Egypt

Sandflies were surveyed 3 times during 1989 in Mersa Matruh city and Siwa oasis to investigate their status. Only Phlebotomus papatasi was identified from inside houses and outdoor sites. More flies were collected in Mersa Matruh than in Siwa. Results document for the first time the presence of P. papatasi in Mersa Matruh and verify its presence in Siwa oasis

Development of cholinesterase activity during the life cycle of two mosquitoes

The cholinesterase [ChE] activity of Culex pipiens and Anopheles pharoensis increased progressively from egg to adult stage. Females had a higher activity per individual, and a lower activity per mg tissue than males. The adult head contained a greater activity than the trunk. These results were significantly different at the 5% level

Effect of organophosphorus insecticides on cholinesterase activity in mosquitoes

The toxicity and the in vivo and in vitro cholinesterase [ChE] inhibitory action of malathion, diazinon and dipterex were of a higher rate against the fourth larval instar of Anopheles pharoensis than of Culex pipiens. In both species, malathion was the most toxic and potent in vivo ChE inhibitor, followed by diazinon and dipterex respectively. However, diazinon was the most potent in vitro ChE inhibitor, followed by dipterex and malathion respectively. The inconsistancy of in vitro inhibition with the order of toxicity is discussed

Cholinesterase specificity in two mosquito species

Cholinesterase [ChE] in the fourth larval instar and adults of Culex pipiens and Anopheles pharoensis is largely of the specific type. ChE activity was the highest towards Acetylcholine bromide [ACh] hydrolysis, and decreased progressively towards Acetyl B-methykholine bromide [AMeCh] and benzoylcholine chloride [BzCh]. BzCh was not hydrolyzed by ChE from the adult head