Ricinidae

Definition

A family of chewing lice in the suborder Amblycera (order Psocodea) comprising relatively large-bodied ectoparasites of birds. Unlike most chewing lice, which feed on feathers and skin debris, ricinids are atypical hematophages that pierce host skin to feed on blood. They characteristically exhibit low prevalence and low intensity infestations, with strongly female-biased sex ratios that become more pronounced at lower intensities. The family includes two or three recognized genera: Ricinus (broadly distributed on birds), Trochiliphagus (specialized on hummingbirds), and Trochiloecetes (also hummingbird-associated).

Etymology

From Ricinus (type genus, from Latin ricinus 'dog tick') + -idae (family suffix)

Example

Ricinus species infest a wide range of avian hosts including pigeons and passerines, whereas Trochiliphagus and Trochiloecetes are restricted to hummingbirds, illustrating host specialization within the family.

Related Terms

• Amblycera
• Psocodea
• chewing lice
• Ectoparasite
• Hematophagy
• Ricinus
• Trochiliphagus
• Phthiraptera

Usage Notes

The family is distinguished from other Amblycera by its blood-feeding habit and large body size relative to other avian lice. The female-biased sex ratio is a notable demographic feature used in population studies of avian ectoparasites. Some authorities recognize only two genera (excluding Trochiloecetes), so genus counts may vary by source. The family name is sometimes encountered in older literature as Ricinidae Neumann, 1890, reflecting its original description.