MORPHOLOGICAL AND BIOLOGICAL DIFFERENCES BETWEEN THE INFECTIVE LARVAE OF ANGIOSTRONGYLUS CANTONENSIS AND THOSE OF ANAFILAROIDES ROSTRATUS

Abstract

Third-stage larvae of the rat lungworm, Angiostrongylus cantonensis, can be differentiated from those of the cat lungworm, Anafilaroides rostratus, on the basis of shorter body length, shorter esophagus, and in some cases on the position of the genital primordium. In A. cantonensis the length of the body is 460 to 510 μ and the length of the esophagus, including the buccal cavity, is 171 to 198 μ. The genital primordium is 120 to 135 μ from the anal opening. In A. rostratus the length of the body is 545 to 655 μ, and that of the esophagus is 218 to 246 μ. The genital primordium is 37 to 153 μ from the anal opening. The infective larvae of A. rostratus do not migrate to the central nervous system as do those of A. cantonensis. The larvae of A. rostratus have been found to re-encyst in the liver of rats and mice which serve as paratenic hosts.