Lec-5 stage -3 Sub Order: Nematocera Fam:Simuliidae This family comprises 75 described species in the same genus . 1- Simulium, most widely distributed species in America ,Asia, Africa, the anther genus are :2-prosimulium ,3- Austrosimulium The characteristics of blackly 1-Tiny blood-sucking flies. 2-They are small dipterous insects ranging from 1 to 4 mm in length. 3- The antenna consisting of eleven segments (same in both sex). Larvae: 1- They brown to whitish larvae are cylindrical ,twelve-segmented, slightly thinner in the mid region and when fully grown are from 10-15 mm ,in length. 2- The posterior and of the body is provided with a toothed disk-like sucker. 3- The anterior pro leg supplied with toothed disk. 4- The larvae moves from place to another place with looping manner . 5- The Fan-shaped filamentous structures located on the head of which food is drawn to the mouth. 6- On the last abdominal segment retractile structures (rectal gill)

Larvae

Looping manner

Cephalic fan

Pupa: 1- the pupae are quiescent Pupa: 1- the pupae are quiescent. 2- They are provided interiorly with a number of long tracheal filaments .which are also importance in classification. The adult: Male eyes meeting female eyes not meeting (Holoptic eye) (dichoptic eye) Life cycle 1- Eggs are laid in running water on the surface of rocks,grass and other debris. 2- The larvae attach themselves to rocks. 3- Breeding success is highly sensitive to water pollution. 4- the larvae use tiny hooks at ends of their abdomens to hold on to the substrate. 5- Adult males feed on nectar while females also feed on blood.

Pupa

Pupa

3- Less common severe allergic reactions may require hospitalization. Adult behavior : 1-Only three genus in the Simuliidae family Simulium, Prosimulium, Austrosimulium.e Contain species that feed on people. 2- Other species prefer to feed on other mammals = (Zoophilie) محبة للحيوان غير الانسان or on birds =(ornithophilic)محبة للطيور Medical important 1- Annoyance Itching and localized swelling and inflammation sometimes occurs at the site if a bite . 2- Intense feeding can cause (black fly fever)with headache ,fever, swollen lymph nodes and aching joints. 3- Less common severe allergic reactions may require hospitalization. 4- River blindness عمى الانهار black flies are central to the transmission of the parasitic nematode Onchocerca volvulus which causes (Onchocerciasis )or River blindness. 5- The parasite lives on human skin and is transmitted to the black fly during feeding. The vector :Simulium damnosum

The control 1- control black flies is difficult task because this insect deposit its eggs in running water which used by human and animal . 2- To prevent annoyance ,some form of spray or ointment may be applied, to the skin and face keeps the insects away. 3- Wearing heavy -duty ,light-colored clothing, including long-sleeve, shirts ,long pants and hats.