This document discusses the classification, life cycle, morphology, and medical importance of Tabanid flies. It begins by classifying Tabanids in the animal kingdom and notes there are over 4,300 species worldwide. It then describes the fly's life cycle from egg laying near water, to larvae feeding in water/mud, to pupae and finally adult flies. Key details about identifying species based on wing patterns and differentiating males and females are provided. The document concludes by explaining Tabanids can transmit diseases like loa loa filariasis and tularemia, and their bites cause blood loss in animals, which in severe cases of hundreds of ml per day.

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

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.

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

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.

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.

7.  The eggs are white at first, but darken with age.

8.  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.

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

10.  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.

13.  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.

14.  2-Haematopota:
 The wing has a characteristic mottling.

15.  3-Tabanus:
 The wings are clear and are held horizontally during
rest.

16.  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.

17.  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.