Syrphidae

These flies are 6-12 mm long and brightly colored yellow and black. They are often seen hovering around flowers. Others are 12-20 mm long, brown to dark brown flies associated with decaying organic matter. Many species resemble bees and wasps; some look like honey bees and some bumble bees. The drone fly, Eristalis tenax, resembles a honey bee in appearance and sound. Larvae of this species are found in decaying organic matter. Aristotle theorized that honey bees could be generated from the dead carcass of an ox. Indeed, this substrate may have provided a breeding site for the saphrophagous larvae of E. tenax, and the honey bees he saw may have been the adult flies.

Syrphid larvae feed on a variety ofmaterials, including primary invaders of living plants, predators of aphids and other homopterans, secondary feeders on decaying vegetation and animal feces, and living in the nests of ants, termites, and bees. Larvae of species associated with wet decaying organic matter and animal feces have a long extension of the body and the posterior tracheal trunk (Fig. 7.2c). These are called rattail maggots. The end of the rattail is the respiratory tube. This tube consists of three segments; when contracted, the second and third are telescoped into the first. When fully distended the respiratory tube is usually several times the length of the body. This larval form is found in species with saprophagous larvae, including Eristalis tenax, E. dimidata, E. aeneus, E. arbustorum, and Helophilus pendulus.

Eristalis arbustorum Adults are about 11 mm long and dark brown to blackish brown. The head is produced anteriorly, the face is entirely covered with fine, pale white setae, and the eye lacks a zone of dense pile in the median third. Abdominal segments 2-4 have narrow apical, yellow bands; there are prominent yellow spots on abdominal segment 2 and sometimes segment 3. Abdominal segment 3 has a pre-basal and a preapical black band. Middle tarsi are reddish brown at the base. Full-grown larvae are 15-18 mm long, cylindrical (excluding caudal portion); the cephalic end is blunt and the caudal end terminates in an elongated breathing tube. The cuticle is yellowish white, translucent, and covered with fine setae. Abdominal segments 1-6 have short, ventral prolegs bearing numerous hooks. Prothoracic spiracles are pigmented and with 10-12 openings. The caudal breathing tube is about 50 mm long, and terminates in a circle of plumose setae. Larvae ofthis species have been found in organic-rich water from sewer systems and animal waste.

Rattailed maggot, drone fly, Eristalis tenax (Fig. 7.2c) Adults are about 15 mm long and dark brown to yellowish brown. The head is produced anteriorly, the thorax is covered with fine setae, the abdomen is shiny and has black and yellow markings. Full-grown larvae are 17-20 mm long, pale yellow to yellowish white, with distinct prolegs on the mesothorax and abdominal segments 1-6. The larvae have anal gills and a long respiratory tube, which provides the common name of rattail. The puparium retains the long rattail, and the pupal respiratory horns are long. The long tail functions as a type of snorkel, allowing the larva to take air from the surface while feeding on the bottom. The mouthparts consist of coarse and fine filters to remove particles of food that enter the mouth. Water is sucked in and then forced out to clean the filters and prevent clogging. This species is distributed worldwide, except for some tropical regions. In about 1870 it spread through Asia to western North America, and by 1884 it was common throughout the USA. It reached New Zealand in 1888. Larvae occur in wet compost, decaying animal carcasses, and feces; they are common in urban and farm sewerage water and septic tanks. Larvae are extremely resistant to adverse environmental conditions.

How To Become A Bee Keeping Pro

How To Become A Bee Keeping Pro

Companies that have beekeeping stuff deal with all the equipment that is required for this business, like attire for bee keeping which is essential from head to torso, full body suits and just head gear. Along with this equipment they also sell journals and books on beekeeping to help people to understand this field better. Some of the better known beekeeping companies have been in the business for more than a hundred years.

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