Oswaldocruzia

  

Contents

  

Rev: 08/24/2026

  Classification Biology and Ecology
Morphology and Anatomy Life Cycle
Return to Oswaldocruzia Menu Ecosystem Functions and Services
Distribution Management
Return to Molineidae Menu Feeding  References
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Classification:

         Chromadorea

Chromadoria

         Rhabditida

Rhabditina

             Infraorder Rhabditomorpha
                  Molineoidea
       Molineidae
Molineinae
                   
                  Oswaldocruzia Travassos, 1917
      Type species of the genus:  Oswaldocruzia filiformis (Goeze, 1782) Travassos, 1917

    Synonyms:
     

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Morphology and Anatomy:

General charcteristics:

 

 

Females:

Ref: Willkens et al., 2025; Slimane et al., 1996

Males:  

  • Spicules with 3 branches: blade, shoe and fork
  • Spicule morphology varies among biogeographical groups: (a) Oriento Ethiopian, with 2-3 indistinct tips; (b) Neo-Ethiopian, with numerous indistinct tips; (c) Caribbean,with 3 main branches subdivided into numerous tips; and (d) Holarctic and (e) Neotropical, both with 3 branches forming a �fork�, �blade� and �shoe� (Slimane et al. 1996)
  • Caudal bursa type II

Body size range for the species of this genus in the database - Click:
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Distribution:

Species have been described from several countries in South and central America and the Carribean.  Recorded from toads, frogs and tree frogs.

The genus Oswaldocruzia  is cosmopolitan with around 90 species that are mainly parasites of toads and frogs but also  of  salamanders, lizards and, rarely, snakes. As of 2013, 30 species were reported from South America and 9 in Caribbean Islands (Guerrero, 2013).

Guerrero (2013) notes that the true toad, Rhinella  and other Bufonidae have great biodiversity and distribution of the genus so that further undescribed species of Oswaldocruzia may be found. Many of the species may be very closely related. Gene sequencing and molecular analyses, in combination with morphological will be necessary to decipher the diversity and evolution of this genus.

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Feeding:

Food Sources and Feeding strategies for the genus Oswaldocruzia

Parasites of amphibians

At least 38 species are parasitic in Bufonidae (true toads) around the world and around 25% of those are in Rhinella marina, the cane toad (Guerrero, 2013).

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Biology and Ecology:

 

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Life Cycle:

Studies on O. filiformis and O. pipiens demonstrated that the parasitic life cycles are direct and probably by skin penetration. Amphibians have smooth skins covered with mucus secretions that are more accessible to infective larvae whereas reptiles are covered in overlapping epidermal scales, reducing the area exposed to infection. That may contribute to the higher frequency of infections in amphibians (Baker, 1978; Hendrikx, W.M.J. 1983; Willkens et al. 2025).

For Ecophysiological Parameters for this genus, click 
 
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Ecosystem Functions and Services:

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Management:

 
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References:

Baker, M.R. 1978. Development and transmission of Oswaldocruzia pipiens Walton, 1929 (Nematoda: Trichostrongylidae) in amphibians. Canadian Journal of Zoology 56: 1026-1031. https://doi.org/10.1139/z78-145

Guerrero, R. 2013. Two new species of Oswaldocruzia (Nematoda: Trichostrongylina: Molineoidea) parasites of the cane toad Rhinella marina (Amphibia: Anura) from Peru. Acta Parasitologica, 2013, 58:30-36; ISSN 1230-2821

Hendrikx. W.M.I. 1983. Observations on the routes of infection of Oswaldocruzia filiformis (Nematoda: Trichostrongylidae) in amphibia. Zeitschrift f�r Parasitenkunde 69:119-126.

Slimane, B.B., Chabaud , A.G., and Durette-Desset, M.C. 1996.  Les nematodes trichostrongylina parasites d�amphibiens et de reptiles: problemes taxonomiques, phyletiques et biogeographiques. Systematic Parasitology 35:179-206. https://doi.org/10.1007/BF00009639

Slimane, B.B., Guerrero, R., Durette-Desset, M-C. 1996. Oswaldocruzia venezuelensis sp. n. (Nematode: Trichostrongylina, Molineoidea), a parasite of Bufo marinus from Venezuela. Folia Parasitologica 43:297-300.

Travassos, L. 1917. Trichostrongylidas brasileiras. Brazil M�dico 31:3-4.

Willkens, Y., Santos, J.N., Melo, F.T.V.V. 2025. Molineid nematodes of amphibians and reptiles: A checklist of Caribbean, Panamanian, and Neotropical species and notes on their biology and host associations. Parasitology 153:169-185. https://doi.org/10.1017/S0031182025101364

 
Revised by Howard Ferris.
Revised: August 24, 2026.