Lab 7 -Slide Observation of Adult Mosquito- Subfamily: Anophelinae &Culicinae
Title: Differentiate Of Male And Female Mosquitos:Family Culicidae
Introduction
The distribution of the mosquito is worldwide, it were occur the tropical and temperature regions. It were absent on Antarctica and a few island, it can be up to 3500m and down 1250m sea level, the mosquito family have three family toxorhynchitinae,anophelinae and culicinae.the most important pest and vector species belong to the genera anopheles ,culex,aedes,ochlerotatus,psorophora and sabethes .the mosquito is the bloodsucking insect that responsible to the many type of diseases in the world. it also as the vector.
Objective:
1. To differentiate the general morphology of adult between male and female
2. To identify the external morphology that differentiate between male and female mosquito belonging to the subfamily anophelinae
3. To identify the external morphology that differentiate between male and female mosquito belongings to the family culicinae
Methodology:
1. Observed the slide male and female mosquito in the subfamily anophelinae
2. Observed the slide male and female mosquito belongings to the subfamily culicinae
Discussion
The antennae are plumose in male and pilose in the female.Adult size 1.6-12.5 mm in length. Divided into head, thorax, and abdomen. The head is sub globose, with a pair of antennae, compound eyes, maxillary palpi, and one proboscis. Thorax is divided into pro, meso, and metathorax. The mesothorax is well developed, with a pair of wings. One pair of legs on each thoracic segment. A pair of halteres on metathorax.. Abdomen is composed of 10 segments, 8 visible, the last 2 modified to form genital organs, 7 pairs of spiracles on the anterior 7 segments.
The head of the mosquito have maxilla, hypo pharnrynx ,labellum,labium,labrum and mandible. The proboscis is used to the blood sucking on the skin; The antennae are an insects primary, non-visual, sense organs, though in a few rare instances they have become adapted for other purposes.
Mosquito are slender ,delicate flies that are generally less than 6mm long, they have sucking proboscious the distinguish them from gnat and midget. Only female bite and suck blood, male can draw blood and nectar and fruit juice. Female have plain antenna because they have no need for the more elaborated antenna that males use to find female. The female find warm blooded animal by following trails of exhaled carbon dioxide. Mosquito need find standing water in which to lay egg thus abundant in wet seasons and perpetually humid climate.
Mosquitoes are relatively small insects, measuring an average of just more than 6 mm long and weighing about 2.5 milligrams. They're divided into three basic parts: the head, thorax and abdomen. The head is crammed with sensory equipment that help the mosquitoes find and feed on people and animals.
They have two large compound eyes covered with tiny lenses called ommatidia that are capable of detecting even slight movement. On the top of their heads, they also have ocelli, simple photosensitive eyes detect variations in light. Their antennae, long feathery organs, jut forward from their heads and contain sensitive receptors that detect carbon dioxide in human breath from distances of more than 100 feet. The maxillary palp between the antennae picks up the odor of ocentol and other chemicals released in human sweat.
Right in the middle, also between the antennae, is the proboscis, a long serrated mouthpart used to pierce the skin and suck out blood. The proboscis holds two tubes, one that injects saliva containing an anti-coagulant and mild painkiller, and a second that actually draws the blood. The thorax, or what you might think of as the torso, is connected to the head. A pair of wings and a pair of halters, small wing-like organs used for steering, sprout from the thorax. The legs also come out of the thorax, six in all, with tiny claws at the end of each to help the mosquitoes stay attached to surfaces.
The abdomen hangs from the thorax and serves as the mosquitoes' stomach and lungs. Small openings called spiracles line both sides of the abdomen, allowing the mosquitoes to draw in air. The abdomen holds the blood that female mosquitoes take in, and a nerve in the abdomen signals when it is full. A female's eggs are also stored in the abdomen. Scientists use small differences in the shape and coloring of the abdomen, as well as in the length of the maxillary palp and wings, to identify the various species of mosquito.
The antenna of the male and female not same the male is bushier than female. The antenna of the male is long than proboscios the male culicinae is tip not club-shaped and tip club shaped for male anophelinae.the female palp is short, but the male are long palp.
The palps in both sexes are as long, or nearly as long, as the proboscis. The scutellum is rounded. Wings of nearly all species have characteristic patterns of pale and dark spots of scales .The subfamily Anophelinae was divided by Edwards into three genera: Chagasia (scutellum slightly trilobed), Bironella (scutellum evenly rounded, wing with stem of median fork wavy) and Anopheles (scutellum evenly rounded, wing with stem of median fork straight). The genus includes more than 400 species. When settled, most Anopheles stand with the proboscis, head and abdomen in almost a straight line, usually resting on an upright surface at an angle of about 45°; exceptionally, as in A. culicifacies, the resting position adopted is more Culex-like .In flight the hum produced by Anophelesis low pitched, almost inaudible unless close to the ear. Most species require large spaces for mating flights, rendering it difficult to propagate them in captivity.
This large and heterogeneous subfamily of mosquitoes contains over 2500 species and some 30 genera. The scutellum is trilobed, each lobe bearing bristles. The abdomen is blunt and completely clothed with broad flat scales. The eighth segment of the larva bears a patch of comb teeth on each side, used for cleaning the mouth brushes, and is drawn out into a respiratory siphon, with well developed pecten teeth in a row on each side. There are no abdominal palmate hairs (cf. Anopheles). Below the siphon the anal segment of the larva bears a chitinous saddle, four gills, caudal setae and the ventral brush for swimming. Culicine pupae are similar to those of Anopheles, but the respiratory trumpets are not so flared distally.
The HIV virus cannot be transfer by mosquito by the sucking of the blood from infected people to non infected people.
Conclusion
The morphology of male and female is different from each other also the subfamily is also different from each other.
Questions:
1. Describe the difference between the subfamily of Culicinae and Anophelinae
The palp of the culicinae is tip not club-shaped and the anophelinae is tip club-shaped,the culicinae abdomen are covered dorvasally and ventrally brown ,blackish,whitish scales but the anophelinae abdomen almost,entirely devoid scales.
2. Is it true that mosquito highly attracted to ABO grouping ‘O’ compare to other blood type?
Mosquitoes were more likely to bite people with type O blood than other potential victims, while people with type A got the fewest bites. This phenomenon, claiming that factors such as sweatiness are more likely to influence victim selection. They found type O secretors were twice as attractive to mosquitoes as type A secretors. Scientific studies point to the fact that mosquitoes are attracted to the carbon dioxide in the air that mammals exhale.
References
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