Rev: 02/27/2023

  Classification Biology and Ecology
Morphology and Anatomy Life Cycle
Return to Stilbonema Menu Ecosystem Functions and Services
Distribution Management
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  •         Stilbonema Cobb, 1920


    Type species:  Stilbonema brevicolle Cobb, 1920

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    Morphology and Anatomy:




    • Cuticle coarsely striated, covered with mucus and rod-shaped bacteria.
    • Head capsule well developed.
    • 6 papilliform inner labial sensilla, 6 setiform outer labial sensilla, 4 setiform cephalic sensilla
    • Two circles of 8 subcephalic setae.
    • Somatic setae along body
    • Amphid fovea pore-like.
    • Pharynx muscular, mainl cylindrical, with small pyriform terminal bulb.
    • Conspicuous, elongate cardia.
    • Tail conical with spinneret


    • Didelphic, ovaries antidromously reflexed, both genital branches to the left of intestine.



    • Monorchic,

    • Spicules paired, curved

    • Gubernaculum with or without dorsocaudal apophysis.

    • Conspicuous precloacal supplements at level of pharynx.


    Ref: Armenteros et al., 2014

    Body size range for the species of this genus in the database - Click:
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    Marine nematodes in tidal sands and coral reefs.

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    Nematodes in the subfamily Stilbonematinae of the Desmodoridae are associated with, and feed on,  dense coatings of sulfur-oxidizing chemoautotrophic gammaproteobacteria with which they are apparently obligately symbiotic. The nematodes inhabit environments with low oxygen availability and reducing conditions. Essentially, the nematodes farm their bacterial associates by migrating to ocean sediments rich in hydrogen sulfide (Bulgheresi Reference Bulgheresi2011; Murfin et al. Reference Murfin, Dillman, Foster, Bulgheresi, Slatko, Sternberg and Goodrich-Blair2012; Blaxter, M. and Koutsovoulos, G. 2015)




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    Biology and Ecology:


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    Life Cycle:

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

    Transfer  ectosymbiotic bacteria among sulfidic and oxidized layers of sediiment (Moens et al., 2014)

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    Armenteros, M., Ruiz-Abierno, A., Decraemer, W. 2014. Taxonomy of Stilbonematinae (Nematoda: Desmodoridae): description of two new and three known species and phylogenetic relationships within the family. Zool; J. of the Linnean Soc. 171:1-21.

    Blaxter, M. and Koutsovoulos, G. 2015. The evolution of parasitism in Nematoda. Parasitology 142: S26-S39.

    Bulgheresi, S. 2011. Calling the roll on Laxus oneistus immune defense molecules. Symbiosis 55:127-135.

    Chitwood, B.G. 1936. Some marine nematodes from North Carolina. Proc. Helmint. Soc. Wash. 3: 1-16.

    Murfin, K. E., DillmanA. R., FosterJ. M., BulgheresiS., SlatkoB. E., SternbergP. W. and Goodrich-BlairH. 2012. Nematode-bacterium symbioses - cooperation and conflict revealed in the Omics� age. Biological Bulletin 223: 85-102.


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    Copyright © 1999 by Howard Ferris.
    Revised: February 27, 2023.