The agents for Linguatulosis are organisms within the genus Linguatula, primarily the species Linguatula serrata.
Linguatulids are an unusual group of organisms because they share both arthropod and annelid characteristics. There are, therefore, some experts who classify Linguatulids under either the phylums Arthropoda or Annelida. An example of one such classification, from Martin and Davis, is shown in Table 1. However, other experts believe that it is difficult to justify assigning pentastomids to either the Arthropoda or Annelida phylum (Self, 1969; Nobel and Nobel, 1982). They, therefore, assign pentastomids an independent phylum, Pentastomida, with the belief that pentastomids once had common ancestors with Annelida and Arthropoda. An example of this classification is shown in Table 2 (Nobel and Nobel, 1982; John and Petri, 2006)
Linguatula serrata is one of the most common, studied, and understood species of the linguatulids (Nobel and Nobel, 1982). In fact, Linguatula serrata corresponds to over 99% of reports from pentastomid infection (Lazo et al., 1999). Another common species of Linguatula is L. rhinaria, common in lifestock and facultative in man.
Linguatulosis may also be called linguatuliasis, nasopharyngeal pentastomiasis, halzoun (Middle East), and Marrara syndrome (Sudan). Linguatulids are commonly called Tongue-worms, which consist of species within the phylum Pentastomida (Siavashi et al., 2002; John and Petri, 2006).