The internal anatomy of the mite Listrophorus leuckarti

S ummary1 The endites of the pedipalps form an apparatns for gripping the hair. 2 The pedipalpal endite has powerful adductors but shorter and weaker abductors. 3 Taking the musculature and curvature of the endites into consideration, it seems unlikely that the animal can release the hair. 4 The food appears to be scales and the secretions of epidermal glands scraped off the hair by the chelicerae. 5 The gut has virtually lost the lateral caeca of the more typical Sarcopti‐formes, and shows no clearly differentiated post‐colon. 6 The female reproductive system has developed a long median glandular common oviduct. 7 The female system shows the bursa copulatrix and receptaculum seminis typical of Tyroglyphoidea. 8 By loss of accessory glands the male reproductive system has come to resemble that of the female quite closely. 9 The posterior region of the suboesophageal ganglion mass is subdivided into a pair of lobes. Each lobe innervates legs III and IV, the genital valves and dorso‐ventral muscles of its own side. 10 The muscles associated with movements of the gnathosoma on the podosoma are lost. 11 Development of lateral plates on the tectum of the gnathosoma and extensions of the epimera of leg I to articulate with the pedipalpal coxae render the gnathosoma immobile. 12 The adductor system of the legs is modified in that it has its origins not on the body wall or tendinous endoskeleton but on the epimera in the case of legs I and II and on the posterior end of the sternum or an internal projection of the body wall in the case of legs III and IV respectively.