Sectonema ventrale

Sectonema ventrale	Contents	Rev 08/03/2020
	Classification	Biology and Ecology
	Morphology and Anatomy	Life Cycle
Return to Sectonema Menu		Ecosystem Functions and Services
	Distribution	Management
Return to Aporcelaimidae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification:

Enoplea

Dorylaimia
Dorylaimida

Aporcelaimidae

Sectonematinae

Sectonema ventrale Thorne, 1930

Morphology and Anatomy:

Very large nematodes, 7-10 mm.
Cuticle with fine striations and criss-cross lines.
Labial region 25-27 µm wide, strongly offset from body contour, lips separated.
Amphid fooveae cup to stirrup-shaped, openingat head constriction and almost half lip-region diameter.
Spear is a straight mural tooth on ventral wall of stoma, 12-14 µm long . The mural tooth is attached to an odontophore almost 4x its length. Pena-Santiago and Alvarez-Ortega (2014) concluded that the spear appears to be a reduced odontostyle rather than a typical mural tooth and suggest the need for further studies.
Enlarged portion of esophagus occupies almost 68-73% of total esophagus length.
Esophagus and intestine separated by a disc.
Female gonad diovarial, amphidelphic; V= 48-56, vulva a transverse slit with sclerotized inner lips. Pars refringens vaginae well developed; uterus length 2.5-4.2 x body diameter at vulva..
Male spicules strong, 120 µm long.
Tail similar in both sexes, short conoid, conoid-rounded, 47-71 µm long, c=117-174, c'=0.7-0.8l.

Ref. Pena-Santiago and Alvarez-Ortega (2014); Andrassy (2009).

Sectonema ventrale, female anterior.

From Thorne, 1930

Sectonema ventrale female posterior

Female:

Males:

Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

Distribution:

Reported from western USA in cultivated fields in Utah, Colorado, Idaho and California (Thorne, 1930).

Categorized as predators and omnivores (Yeates et al., 1993).

Observed to feed on oligochaetes (Thorne, 1930).
When the nematode attacks its prey, the tooth is thrust into the body of the victim. The body wall is cut by a dorsal to ventral slash of the tooth (Thorne, 1930).

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Biology and Ecology:

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Life Cycle:

Ecophysiological Parameters:

For Ecophysiological Parameters for this species, click	If species level data are not available, click for genus level parameters

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Ecosystem Functions and Services:

Regulation of opportunistic species by predation.

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Management:

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References:

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

Pena-Santiago, R. and Alvarez-Ortega, S. 2014. Studies on the genus Sectonmea Thorne, 1930 (Dorylaimida: Aporcelaimidae. Redescription of S. ventrale Thorne, 1930, the type species of the genus. Nematology 14:1097-1104.

Thorne, G. 1930. Predacious nemas of the genus Nygolaimus and a new genus, Sectonema. Journal of Agricultural Reaearch 41:445-466.

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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