Cyathorobbea		Contents		Rev: 05/20/2025
		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Cyathorobbea Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Desmodoridae Menu		Feeding		References
		Go to Nemaplex Main Menu		Go to Dictionary of Terminology

Classification:

Chromadorea

  Chromadoria

   Desmodorida

Desmodorina

             Deamodoroidea

                Desmodoridae

       Stilbonematinae

        Cyathorobbea Scharhauser, Saavedra, Prots, Ott, Geier, Gruber-Vodicka, Polikarpov, Bourenkov & Leisch, 2025

     

Type species of the genus: Cyathorobbea tenax Scharhauser, Saavedra, Prots, Ott, Geier, Gruber-Vodicka, Polikarpov, Bourenkov & Leisch, 2025

    Synonyms:

Robbea Gerlach, 1956

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Morphology and Anatomy:

Based on PCA analyses of multiple characteristics, Scharhauser et al (2025) concluded that species of Cyathorobbea were clearly different from those of Robbea, thus supporting establishment of the new genus.

• Stilbonematinae; body length 1.8-4.5 mm; body stout (a < 110), cuticle thin, transverse striation extremely fine,
• Cephalic capsule with block layer, creating a honey-comb structure in surface view;

• Head capsule with thickened cuticle,

• Sensilla in 6-6-4 pattern, papilliform and setiform, first circle of finger-like papillae retracted into mouth opening, second as six conical papillae at margin of buccal membrane, third as four long cephalic setae directed anteriorly, close to the anterior margin of the amphidial fovea;

• Somatic setae of variable length,
• Glandular sense organs (GSOs) colorless, in 8 rows
• Amphidial fovea variable with spiral  or loop-shaped groove, ventrally wound.
• Pharynx with swollen muscular corpus, set off from the long and thin isthmus, small mainly glandular terminal bulb. .
• Body diameter decreases at onset of bacterial coat,  Bacteria arranged with their longer axis parallel to the cuticle
• Tail conical or cylindro-conical

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Distribution:

Marine nematodes in tidal sands and coral reefs.

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Feeding:

Food Sources and Feeding strategies for the genus Cyathorobbea

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)..

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Biology and Ecology:

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Life Cycle:

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Ecosystem Functions and Services:

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Management:

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References:

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.

Gerlach S.A. 1956. Die Nematodenbesiedlung des tropischen Brandungsstrandes von Pernambuco: Brasilianische Meeres-Nematoden, II. Kieler Meeresforschungen 12:202-218.

Murfin, K. E., Dillman, A. R., Foster, J. M., Bulgheresi, S., Slatko, B. E., Sternberg, P. W. and Goodrich-Blair, H. 2012. Nematode-bacterium symbioses - cooperation and conflict revealed in the omics age. Biological Bulletin 223, 85-102.

Scharhauser, F. et al. 2025.  Revision of the genus Cyathorobbea (Stilbonematinae: Desmodoridae), worldwide abundant marine nematodes with chromophoric Fe–Br inclusions and the description of a new stilbonematine genus, Zoological Journal of the Linnean Society, 203, Issue 1, January 2025, zlae005, https://doi.org/10.1093/zoolinnean/zlae005

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Copyright © 1999 by Howard Ferris.
Revised: May 20, 2025.