Anatomy and affinity of the elephant louse Haematomyzus elephantis Piaget (Insecta: Rhyncophthiraptera)

Abstract

Detailed accounts of the morphology of the elephant louse and of its phylogenetic affinities and origin are given. The main points noted are: The peculiarity of the knobs and plate in the head are described. The mouthparts are described, a notable feature being the rotation of the mandible to 180 degrees. Structural peculiarities of the thorax with the muscles are given. The abdomen is found to consist of eight segments. The alimentary canal is described; no crop has been found. The histology of Weber's organ is given, and it is held that this organ is excretory in function. The structure of the spiracle is described, no spiracular gland has been found. The reproductive organs are described. In the female, the follicular epithelium of the ovary is binucleate and a spermatheca is present. In the male, the testis is bi-follicular. The affinities of the elephant louse are discussed and the creation of a new order, the Rhyncophthiraptera, to accommodate Haematomyzus, is suggested.