Tabanidae species - tabanus

life cycle, morphoogy, species, bionomics and habitat and medical importance

1. By Montasir Ghaneim Alzain M.Sc in Medical Parasitology / UOG Tabanidae Species

2. By the end of this lecture each student should: Understand the classification of Tabanid flies. Know their life cycle, bionomics and habitat. Describe the basic morphology of the fly and how to differentiate between species. Know the medical importance of the fly. Learning objectives

3. Kingdom: Animalia Pylum : Arthropoda Calss : Insecta Order: Dipetra Suborder: Brachycera Family: Tabanidae Genus: Tabanus , Chrysops and Haematopota Species: over 4300 Scientific classification

4. Tabanid species are also known as: Horse fly. Deer fly. Breeze fly. In Sudan, between Baggara , in Western Baggara they are known as Elghibaisha , between Eastern Baggara known as Tour Gafal , the Surret and El Teir . In Nuba mountains they called Umm Kokab or Umm bong . Over 4300 species. Worldwide distribution. Introduction

5. The life cycle of tabanids begins with laying of the eggs in clusters (≈ 1000 egg) near water usually on overhanging plant branches. The larva hatches after 4-7 days and drops into the water or mud where it disappears. The larva feeds on earthworms or even on each other . Finally, the larva moults into pupa which lasts 10-14 days under optimal conditions to become adult. Under adverse conditions the larva may hibernate . Life cycle of Tabanid

6. The eggs are white at first, but darken with age. Eggs of Tabanid

7. They are white, but in some, they are greenish or brownish . They have small heads and segmented ( 11 or 13 segments ) and they often have dark bands on each segment. Larvae of Tabanid

8. The pupae are brown and glossy , segmented, each segment is fringed ( short spines ), rounded at the head end and tapering at the other end. Pupa of Tabanid

9. Male or female: Horse flies have large eyes, which are almost contiguous in the male ( holoptic ) and separated by a narrow space in the female ( dichoptic ) and project beyond the margins of the thorax. General morphology of adult Tabanid

10. Differentiation between species using their wings: 1- Chrysops : The wing has a dark band passing from the anterior to the posterior margin and the eyes have metallic color. General morphology of adult Tabanid

11. 2-Haematopota: The wing has a characteristic mottling . General morphology of adult Tabanid

12. 3-Tabanus: The wings are clear and are held horizontally during rest. General morphology of adult Tabanid

13. Flies are very active in clear bright days . Both male and female feed on fruit juices and honey dew . However, female must obtain a blood meal for maturation of the eggs . Most feed during the daytime, locate host by site and CO2 . Prefer dark objects , will bite through colored clothing. Several small meals often taken from the same or different host. Meals are digested at rest on the underside of leaves and stones . Tabanids feed chiefly on large vertebrates especially horses and cattle . Bite is painful. Biology of adults and habitat

14. Species of the genus chrysops transmit the parastic filarial worm loa loa between humans. They can transmit tularemia between rabbits and humans Reports of horse-fly bites leading to fatal anaphylaxis in humans have been reported (very rare). Interrupted feeding behavior increases their likelihood of being mechanical vectors of trypanosoma which cause diseases in animals and humans. Blood loss is a common problem in some animals when large flies are abundant. Some animals have been known to lose up to 300   ml!!! of blood in a single day to tabanid flies. Medical importance of Tabanid