Chapter 236 - Siphonaptera: (Fleas)

Abstract

This chapter discusses the Siphonaptera, laterally compressed wingless holometabolous insects. The order contains approximately 2575 species. All species are parasitic in the adult stage and 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, and current research is providing important insights into flea phylogeny and evolution. Most flea species require a blood meal prior to oogenesis and spermatogenesis. With the exception of some species whose reproductive cycle is synchronized with that of their host, there are few studies on the nutritional requirements of adult fleas. Although the larvae of several fleas have been noted to burrow into dead host tissues, those of Uropsylla tasmanica are the only truly parasitic flea larvae that burrow into and feed on the tissues of their live hosts. Some larvae have been documented to feed directly on fresh blood as it is excreted from the anus of feeding adult fleas, but most scavenge on the dried blood residues or animal dandruff and excreta. A few species are predaceous on other small organisms within the nest.