Order Siphonaptera

This is a PPT presentation that cover the general description, morphology, characteristics, and feeding habits of Order Siphonaptera. This presentation includes the first three classifications.

1. SIPHONAPTERA Report by: Veronica Baje

2. Objectives Define Order Siphonaptera and its classification Know the general characteristics and morphology of the flea Discuss Tunga penetrans , its characteristics, morphology, life cycle, reproduction, and feeding habit. Learn the characteristics, morphology, reproduction, and feeding habits of Pulex irritans and Xenopsylla cheopis

3. Order Siphonaptera Etymology: Greek words “ siphon” which means tube or pipe and ‘’ aptera ” which means wingless. They are laterally compressed wingless holometabolous insects. Contains approximately 2572 species in which all are parasitic in the adult stage. Possess mouthparts modified for piercing and sucking, highly modified combs and setae on their body and legs, and legs that are modified for jumping. Some species are vectors of disease. Fleas are holometabolous.

4. General Morphology of the Flea Adult fleas are on average 2.0 to 6.0 mm in length and have laterally compressed bodies. They possess antennae, sucking mouthparts, and (usually) eyes.  All fleas lack wings and have modified hind legs for jumping . Their lateral flatness and glossy surface facilitate moving among thick fur

5. General Morphology of the Flea The females are larger than males of the same species. Both the dorsal and ventral outline of the female are convex, while the dorsal surface of males is almost straight. Body is covered with backwards directed setae. 

6. Classification of Siphonaptera Genus: Tunga Specie: T. penetrans Genus: Pulex Specie: P. irritans (Human Flea) Genus: Xenopsylla Specie: X. cheopnis (Rat Flea) Genus: Ctenocephalides Specie: C. canis (Dog Flea) & C. fecalis (Cat Flea)

7. Tunga penetrans

8. T. penetrans T. penetrans or chigoe flea/jigger is a parasitic insect found in areas with tropical and sub-tropical climates.  It is native to Central and South America, and has been inadvertently introduced by humans to sub-Saharan Africa. A parasitical infestation of T. penetrans is called tungiasis.

9. Characteristics of T. penetrans The chigger is a minute arachnid. Mites penetrate the skin and feed on skin cells that are broken down through an enzyme they secrete from their mouthparts, but they will then leave the host. The adult and the larval forms both feed on other animals. This is not the case with  T. penetrans , as only the adults feed on mammals, and the mature female remains in the host for the rest of her life.

10. Morphology of T.penetrans

11. Life Cycle of T.penetrans The larva will hatch from the egg within one to six days, assuming the environmental conditions are favorable. After hatching, the flea will progress through two instar phases.  About six to eight days after hatching, the larva pupates and builds a cocoon around itself.  An adult flea will emerge from the puparium after 9–15 days. Males are still mobile after a blood meal like other fleas, but the female flea burrows head-first into the host's skin, leaving the caudal tip of its abdomen visible through an orifice in a skin lesion.  orifice in a skin lesion. 

12. Reproduction The male and female T. penetrans does not show interest in the wild. Reproduction only happens once the female is burrowed into the skin of its host. The male flea dies after copulation. In the next two weeks after mating, the female will releases several hundreds to thousands of eggs in through the caudal orifice. These eggs fall off the ground when they are ready to hatch. The female flea then dies and causes infection to the host as the body rots under the thick scales it created to protect it.

13. Feeding Habit The larvae feed on organic debris in the environment 3-4 days after hatching. Adults seek out warm-blooded host for blood meals. Both male and females feed intermittently on their host.

14. Pulex irritans

15. P. irritans P. irritans are found all over the world except the Arctic region. The species may have originated from Central or South America. They thrive in temperate climates P. irritans has three pairs of legs used for walking and running. It also allows them to jump in order to escape or to get onto a host. They are usually found in small colonies or groups. They will move onto the host to feed but are primarily found around the host’s immediate habitat.

16. Characteristics of P. irritans An adult P. irritans is reddish-brown in color. Females are 2.5 to 3.5 mm long while males are 2 to 2.5 mm long. The body is laterally compressed and wingless. The abdomen and thorax are larger than the head. The head is very short and house a small pair of antennae. They have three pair of legs in which each has five segments. Their eggs are oval an white in color.

17. Morphology

18. Reproduction Currently there are no known mating rituals, mate selection or mate defenses exhibited by  Pulex irritans . Like most fleas,  Pulex irritans  mate opportunistically and are polygynandrous. When two fleas see each other, a male will use his maxillary palps to determine if he has encountered a female.

19. Feeding Habit Adult  P. irritans  require blood meals in order to produce offspring. They will feed on most any mammal (including humans), but they most commonly parasitize domestic dogs and domestic pigs. Larvae feed on various organic matter found within their habitat, including feces from the adult fleas as it contains undigested blood.

20. Xenopsylla cheopis

21. X. cheopis Xenopsylla cheopis usually inhabits tropical and subtropical habitats, although it has been reported in the temperate zone as well. Rarely found in cold areas since it requires a tropical/subtropical climate to pupate. Fleas are nidiculous parasites; they live in the host's nest.

22. Characteristics of X. cheopis Adults are 1.5 to 4 mm long and are laterally compressed Its body is about 2.5 mm The body is consists of three regions: head, thorax, and abdomen The head thorax have rows of bristles called combs The flea is wingless but can jump long distances with the help of its legs.

23. Morphology

24. Reproduction No information is available on the mating systems of these fleas. After copulating with a male the female is ready to lay her eggs. She does this at frequent intervals while feeding.  They prefer temperatures of 65 to 80°F with about 70% humidity for egg laying. Higher or lower temperatures inhibit females from laying their eggs. Eggs usually do not hatch on the hosts, rather on their nests since fleas are nidiculous parasites.

25. Feeding Habit Adults of both sexes of  Xenopsylla cheopis  feed on blood. They bite  Rattus rattus  (Black Rat) and other mammals, including humans.  Xenopsylla cheopis  obtains the host's blood through a set of external mouthparts, which consist of the following maxillary lacunae and an epipharynx .