Parastrichosoma recurvum		Contents		Rev 02/23/2024
		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Parastrichosoma Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Trichosomoididae Menu		Feeding		References
		Go to Nemaplex Main Menu		Go to Dictionary of Terminology

Classification:

      Back to Top

Morphology and Anatomy:

Morphologically, the two described Paratrichosoma species, P. recurvum and P, crocodylus are quite similar.

General characteristics of genus:

• Long, slender nematodes, 2-7 mm long, 0.082-0.167 mm diam.

• Cuticle  unusually thick and smooth.

• Cloaca with a thick cuticular lining.

• Males lack  caudal papillae and a distinct lobe on the posterior end

• Male spicule well-developed spicule, which has a cover at the anterior.

• Stichosome present that does not reach reach the intestine. The stichosome consists of single row of rather long and uniformly colored stichocytes with a smooth surface.

•  

• Differences between species

  •  rough transverse grooves on the spicule of P. crocodylus but not on the spicule of P. recurvum

  • protruding polar plugs on the eggs of P. recurvum  but not on the eggs of P. crocodylus.

  • Mesenchynal cells at the esophago-intestinal junction are absent in P. crocodylus but present  in small amounts in P. recurvum,

  •  the posterior end of the ovary extends beyond the anterior end of the rectum in P. crocodylua but does not in P. recurvum

Ref: Lott, 2015; Ashford and Muller 1978, Spratt 1985, Moravec and Vargas-Vazquez 1997.

Paratrichosoma recurvum: A. Posterior end of a male with spicule and everted specular sheath; B. Spinose spicular sheath. C Stichocyte at the middle part of a stichosome; D. Mature egg in the uterus; E. Advanced egg containing a larva from a serpentine tunnel in the host's skin; F. Funnel-shaped everted spicular sheath of a male. Bars: A, D, E 20 um; B 50 um; C 10 um; F 30 um. From Moravec and Vargas-Vazquez, 1998

Back to Top

Distribution:

Most infections are known from crocodilein breeding ponds where crocodiles are being farmed for skins.

Back to Top

Feeding:

 .Host crocodiles may have zigzag trails and scars under and on the epidermis caused by movement  of nematodes under the epidermis and discharge of nematode eggs from the skin into the surrounding environment. The symproms are sometimes known as "creeping disease" because of the trails.

Back to Top

Biology and Ecology:

Back to Top

Life Cycle:

Ecophysiological Parameters:

Back to Top

Ecosystem Functions and Services:

Back to Top

Management:

Managing crocodile densities in crocodile farm breeding ponds to reduce infection probabilities.

Back to Top

References:

Ashford, R. W., and R. Muller. 1978. Paratrichosoma crocodylus n. gen., n. sp. (Nematoda: Trichosomoididae) from the skin of the New Guinea crocodile. Journal of Helminthology 52:215–220.

Lott, M.J. 2015. Nematode community dynamics in Australian vertebrates: Impacts of contemporary captive management prectices. PhD Thesis, Macquarie University, Sydney, Australia..

Moravec, F., and J. Vargas-Vazquez. 1998. First description of the male and redescription of the female of Paratrichosoma recurvum (Nematoda: Capillariidae), a skin-invading parasite of crocodiles in Mexico. Parasitology Research 84:499–504.

Solger, B. 1877. Ueber eine neue Spezies von Trichosoma. Archiv fur Naturgeschichte 43:19–23.

Solger, B. 1933. Ein vergessener Parasit (Trichosoma recurvum) als Ursache von  "creeping disease"; ein literar-hitorischer Beitrag zur vergleichenden Pathologie der Haut der Wirbeltiere. Dermatologische Wochenshrift 96:476-477

, Back to Top

Copyright © 1999 by Howard Ferris.
Revised: February 23, 2024.