Polyplacidae

Definition

A family of sucking lice (suborder Anoplura) commonly known as spiny rat lice, characterized by a dorsoventrally flattened body and rows of spines on the thoracic and abdominal tergites. Members are obligate ectoparasites of rodents and occasionally other small mammals, with a cosmopolitan distribution. The family contains approximately 193 species as of 2010, making it one of the largest families within Anoplura.

Etymology

From Greek poly- (many) + plax, plakos (flat plate, tablet), referring to the multiple flattened, plate-like sclerites bearing spines characteristic of the family.

Example

Polyplax serrata, a member of Polyplacidae, is a common ectoparasite of the house mouse (Mus musculus) and serves as a vector for Rickettsia typhi, the causative agent of murine typhus.

Synonyms

• spiny rat lice

Related Terms

• Anoplura
• Phthiraptera
• Psocodea
• Polyplax
• Sucking lice
• Ectoparasite
• Vector
• host specificity

Usage Notes

The family is distinguished from other anopluran families by the presence of prominent spines on the thoracic and abdominal tergites, contrasting with the smoother cuticle of families such as Pediculidae (human lice). Species identification within Polyplacidae relies heavily on spine patterns and chaetotaxy. The family shows strong host specificity, with most species restricted to particular rodent host genera.