Scanning electron microscopy examination of larval Linguatula serrata Frölich (Linguatulidae: Pentastomida)

The surface structure of larval Linguatula serrata recovered from the abdominal cavity of a slaughtered goat is described as seen by scanning electron microscopy. The subterminal, squarish mouth situated ventrally in the cone-shaped head, was enclosed by four hook pits in a trapezoidal shape in the first and second abdominal annuli, each pit containing a pair of main and accessory hooks. Three pairs of sensory papillae were observed in the first three abdominal annuli and one pair of male genital papillae in the fifth annulus. Except for the anal annulus each of the 80 abdominal annuli was provided with a single, posteriomarginal row of minute spines bearing fine denticles and a median row of fine surface pores containing deep inner-plugged pores. The functional morphology of the spines and pores is discussed.