part_of adult body adult excretory system adult malpighian tubule A pair of thin-walled extremely long, coiled and folded tubules that extend throughout the body. The wall of the malpighiantubules consists of cuboidal or sub-cuboidal epithelial cells. Each malpighian tubule connects to the rectal sac on its lateralmargins. Responsible for extraction and elimination of nitrogenous waste. Normally, the malpighian tubules are filled withsubspherical guanine crystals which are produced in this location. Fig. 10-1, Fig. 10-2, in Biology of Ticks ISBN:0-19-505910-7. TADS:0000163 TADS:0000163 default_namespace simple organ