The Internal Anatomy of the Spiny Rat Mite, Echinolaelaps echidninus (Berlese)

Abstract

Digestive, excretory, nervous, respiratory and reproductive systems were described from serial sections at 6 to 10 [mu], stained with hematoxylineosin. The digestive system consists primarily of a small ventri-culus with 3 pairs of caeca. Two pairs of globose cells or glands are found in the alimentary canal. The paired excretory tubules extend the length of the body and empty into the rectum. One pair of coxal glands is found above and median to the coxae of legs L The nervous system consists of a central brain mass, surrounding the esophagus, and its paired nerves. A single median nerve serves the epipharynx. A vacuo-lated area found medial to the palpal nerves is described. This structure is possibly glandular in function. Cells which are probably sensory in nature occur in the epipharynx and tectum. The respiratory system consists of paired stigmal openings posterior to legs III, atrial chambers, and tracheae. The reproductive system contains a globular ovary, oviduct, and vagina as well as structures found only in gamasid mites including lyrate organ, sacculus foemineus, and ringed tubes. Paired vaginal glands are present. Coition was described from 3 observations. The male turns the female over and slips under the exuviae of the female at the moment of molting.