The Ixodidae are the familyofhard ticksorscale ticks,[1] one of the three families of ticks, consisting of over 700 species. They are known as 'hard ticks' because they have a scutum or hard shield, which the other major family of ticks, the 'soft ticks' (Argasidae), lack. They are ectoparasites of a wide range of host species, and some are vectors of pathogens that can cause human disease.[citation needed]
They are distinguished from the Argasidae by the presence of a scutum.[2] In both the nymph and the adult, a prominent gnathosoma (or capitulum, mouth and feeding parts) projects forward from the animal's body; in the Argasidae, conversely, the gnathosoma is concealed beneath the body.[citation needed]
They differ, too, in their lifecycle; Ixodidae that attach to a host bite painlessly and are generally unnoticed, and they remain in place until they engorge and are ready to change their skin; this process may take days or weeks. Some species drop off the host to moult in a safe place, whereas others remain on the same host and only drop off once they are ready to lay their eggs.[citation needed]
^"Ixodidae". NCBI taxonomy. Bethesda, MD: National Center for Biotechnology Information. Archived from the original on 14 May 2018. Retrieved 28 September 2017. Lineage( full ) cellular organisms; Eukaryota; Opisthokonta; Metazoa; Eumetazoa; Bilateria; Protostomia; Ecdysozoa; Panarthropoda; Arthropoda; Chelicerata; Arachnida; Acari; Parasitiformes; Ixodida; Ixodoidea
^ abD. H. Molyneux (1993). "Vectors". In Francis E. G. Cox (ed.). Modern parasitology: a textbook of parasitology (2nd ed.). Wiley-Blackwell. pp. 53–74. ISBN978-0-632-02585-5. Archived from the original on 2017-02-15. Retrieved 2016-11-06.