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Morphogenesis of larvalSebekia oxycephala (Pentastomida) from a South American crocodilian (Caiman sclerops) in experimentally infected fish


Egg hatching and subsequent larval development of a porocephalid pentastomidSebekia oxycephala, from a crocodilian (Caiman sclerops), in three species of tropical fishes are described. Eggs hatch after about 6 h and primary larvae invade the body cavity. The ensuing five larval stages, which remain unencapsulated, develop at this site amongst the viscera and all of these stages are devoid of hooks. Hooks reconstitute in the 7th (infective) nymph which becomes lightly encapsulated: this stage first appears after about 80 days and by day 100 post-infection most larvae are infective. Sexual development can be detected in 4th stage larvae and females at least are almost ready to copulate by the infective stage. All of the 3rd–6th stages carry hair-like epicuticular extensions which may constitute a physical barrier against host inflammatory responses. Studies with SEM reveal that many of the cephalic sensory papillae support spiky sensilla and the latter also occur singly, or in groups, in characteristic patterns. Sensilla are also disposed in ventro-lateral lines.

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Correspondence to Judith M. Winch.

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Winch, J.M., Riley, J. Morphogenesis of larvalSebekia oxycephala (Pentastomida) from a South American crocodilian (Caiman sclerops) in experimentally infected fish. Z. Parasitenkd. 72, 251–264 (1986).

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  • Inflammatory Response
  • Larval Stage
  • Larval Development
  • Physical Barrier
  • Characteristic Pattern