Experiments on morphological observations of flies
Experiments on morphological observations of flies
This experiment is from the official website of Human Parasitology of Shandong University
Operation method
Experiments on morphological observations of flies
Principle
Flies are one of the four pests that transmit a wide range of diseases, with pathogens including bacteria, viruses and parasites; causing diseases of the digestive tract, respiratory tract, nervous system and eyes. The life history of the fly is holomorphic. The larvae are also known as maggots, and some fly maggots can also cause fly maggot disease. The types of larval breeding sites are complex and vary from species to species. Pupae are mostly found in the soil around the larval breeding sites. Lick-sucking mouthparts of the fly for omnivorous, foot claw pads can secrete mucus and full of fine hairs, is conducive to adherence to pathogens; there is a habit of eating and vomiting while defecating. The flies with piercing-sucking mouthparts are addicted to sucking human and animal blood, which can transmit trypanosomiasis. Attention should be paid to the relationship between the morphological structure and ecological habits of adult flies and disease transmission. Move I. Self-observation housefly greenfly (3) Chrysomyia megacephala: large body, shiny gold-green or orchid-green metallic luster; compound eyes large and bright red, cheeks orange-yellow, fourth longitudinal vein of the wings curved as in Chrysomyia. (4) Aldrichina grahami (Giant-tailed Alyssum): large body, grayish-black thorax with thick and long zonular hairs, abdomen with a greenish-orange metallic luster. (5) Stable rot fly (Muscina stabulans): medium body, dark gray, with four black longitudinal stripes on the dorsal surface of the mesothorax, with interruptions of the two outer longitudinal stripes, and the fourth longitudinal vein of the wing curving gently forward and ending at a distance from the end of the third longitudinal vein. (7) Bellieria melenura: large, gray. The antennal awn ends are glabrous. There are three straight black longitudinal stripes on the dorsal surface of the mesothorax, the curvature of the fourth wing vein is similar to that of the she-fly, and the dorsal surface of the abdomen has black and white tessellated patches. For more product details, please visit Aladdin Scientific website.
1. Adult fly morphology
(1) Pin-inserted specimens: observed with the naked eye or with a magnifying glass. The whole body is densely covered with bristles, and the body is divided into three parts: head, thorax and abdomen.
Head: there is a pair of compound eyes, in addition to the jatropha, the distance between the two compound eyes can distinguish between male and female, the distance between the two compound eyes of females is larger, the distance between the two compound eyes of males is smaller.
Thorax: three pairs of feet on the ventral side. The mesothorax is well-developed with a pair of wings. The back has black longitudinal stripes.
Abdomen: rounded and blunt, divided into ten segments, only five of which are visible in appearance, the rest of the segments being converted into external genitalia, which are normally retracted inside the abdomen.
(2) Slide specimen: observed under low magnification.
Head of the housefly: there is a pair of compound eyes, composed of many hexagonal single eyes. There are three single eyes in the center of the head, arranged in inverted zigzag; a pair of antennae, located in the center of the cheeks between the compound eyes, each consisting of three sections, the third section of the middle part of the antennal awns (hairs), in the form of feathers. The mouthparts are licking and sucking, consisting of a basal rostrum, a middle rostrum and a labellum. The basal rostrum ends with a pair of palatine whiskers. The labrum is well developed, bilobed, and consists of symmetrically arranged grooves (trachea-like structures).
Legs: covered with bristles, divided into five segments: basal, rotary, leg, tibial, and tarsal; tarsal segments end with a pair of claws and claw pads, claw pads densely covered with fine hairs.
Wing: six longitudinal veins without branching, the curvature of the fourth longitudinal vein and the distance between its end and the end of the third longitudinal vein is one of the taxonomic characters.
2. larval (maggot) posterior stomata slide specimen: larvae abdominal section VIII posterior side of a pair of posterior stomata (door), the posterior stomata by the stomatal ring, stomatal buttons and stomatal clefts and other parts of the composition. The morphology of the posterior stomata of the larva is one of the important bases for the classification of flies.
II. Demonstration
1. Morphology of common fly species in China (adult flies)
(1) Musca domestica vicina: small to medium-sized gray-black body with four longitudinal black stripes of equal length and width on the back of the thorax. The fourth longitudinal vein of the wing bends sharply upward at an angle. Its end is close to the end of the third longitudinal vein. The hairs of the antennal awns are feathery in distribution. 
(6) Stomoxys calcitrans: medium-sized body, resembling a housefly, dark gray, characterized by a piercing-sucking mouthparts, antennal awns with fine hairs unilaterally, longitudinal stripes on the dorsal surface of the thorax and the curvature of the fourth longitudinal vein resembling that of a stable rot fly.
(8) Summer Toilet Fly (Fannia canicularis): Body small, dark gray. Antennal awns glabrous. The fourth longitudinal vein of the wing is almost parallel to the third longitudinal vein.