Helmabia		Contents		Rev 04/25/2023
		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Helmabia Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Encholaimidae Menu		Feeding		References
		Go to Nemaplex Main Menu		Go to Dictionary of Terminology

Classification:

Type species of the genus: Helmabia vera Siddiqi, 1971

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Morphology and Anatomy:

The tessellate cuticle of the sub-family Encholaiminae is considered unique among dorylaims.  It is formed by both deep transverse and longitudinal striations.

• Cuticle tessellate, 28-30 longitudinal ridges creating a plate-like pattern..
• Head continuous or slightly offset from body contour.
• 6 of the 10 outer cephalic setae elongated.
• Odontostyle attenuated with no knobs or flanges on the extension
• Expanded posterior part of the esophagus  is an elongate glandulomuscular cylinder, which is different from other Encholaimidae. The cylindrical portion is about one third or more of the length of the whole esophagus.
• Esophagus joins the intestine with a prominent rounded cardia. 
• Tail elongate-conoid.

Ref. Siddiqi, 1971.

Siddiqi (1971) considered the posterior cylindrical esophagus sufficiently different from the terminal esophageal bulb of other Encholaimidae to warrant a new subfamily: Helmabiinae

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Distribution:

Helmabia vera, described.from cultivated soil in Malawi, has the 6 outer cephalic setae 9.5 to 11 mu long, the spear 8 to 9 mu long with lumen invisible in the anterior third and 20 longitudinal striations in the mid-body region. H. veruta, from the same locality, has the outer cephalic setae 5 to 5.5 mu long, spear 10.5 mu , with clearly visible lumen, and 28 longitudinal striations.

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Feeding:

Many members of the superfamily Tylencholaimoidea are considered hyphal feeders (Yeates et al, 1993).

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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:

Andrássy, I. 2009. Free-living Nematodes of Hungary III.  Hungarian Natural History Museum, Budapest. 608p.

Siddiqi, M.R. 1971. Helmabia, a new genus of dorylaimid nematodes with cephalic setae. Zoologischer Anzeiger 186:368-372.

Yeates, G.W., T. Bongers, R. G. M. De Goede, D. W. Freckman, and S. S. Georgieva. 1993. Feeding habits in soil nematode families and genera—An outline for soil ecologists. Journal of Nematology 25:315-331.

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Copyright  1999 by Howard Ferris.
Revised: April 25, 2023.