Discolaimus major

Discolaimus major	Contents	Rev 06/16/2023
	Classification	Biology and Ecology
	Morphology and Anatomy	Life Cycle
Return to Discolaimus Menu		Ecosystem Functions and Services
	Distribution	Management
Return to Qudsianematidae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification:

Enoplea

Dorylaimia
Dorylaimida

Qudsianematidae (see also family Discolaimidae)

Discolaimus major Thorne, 1939

Morphology and Anatomy:

Large nematodes: up to 3 mm long.
Cuticle smooth
Lateral chords with a series of glandular bodies and pores.
Labial region wide, discoid configuration, with small inner liplets. Easily recognized by this feature.
Odontostyle strong, shorter than labial diamter with aperture occupying about half its length.
Prectum 2.5 x anal body diameter.
Female diovarial, amphidelphic.
Vulva transverse, not sclerotized.
Males rare. 4-18 ventromedial supplements.
Tail conoid, curved or bluntly rounded; simmilar in both sexes.

Ref: Andrassy (2009)

Female:	Discolaimus major Drawings fro De Bruin and Heyns, 1992

Anterior	Diovarial, amphidelphic gonads
Males:
Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

Distribution:

Reported widely: North America, southern Africa, Australia.

Feeding:

Categorized as a predator (Yeates et al., 1993) and studied as a predator (Bilgrami and Gaugler (2005).

Biology and Ecology:

Feeding activities of the predatory nematodes Laimydorus baldus and Discolaimus major preying on Hirschmanniella oryzae were studied under laboratory conditions by Bilgrami and Gaugler, 2005:

Discolaimus major killed more prey, and fed and aggregated longer than L. baldus.
Laimydorus baldus consumed prey more rapidly then D. major.
Predator activities at the feeding site were greatest at 30◦C. Predators starved for 6 days detected prey rapidly and aggregated at the feeding site longest.
Predators were increasingly efficient at finding prey as prey density increased.
Prey search and predation abilities of L. baldus and D. major were regulated by temperature, prey density, starvation and prey incubation.

Predators starved for 10 days exhibited maximum response to the presence of prey. Predators detected prey kairomones at distances of 2-3 cm on agar plates (Pervez and Bilgrami, 2000),

Life Cycle:

Ecophysiological Parameters:

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

Ecosystem Functions and Services:

References:

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

Bilgrami, A.L. and Gaugler, R. 2005. Feeding behaviour of the predatory nematodes Laimydorus baldus and Discolaimus major (Nematoda: Dorylaimida). Nematology 7:11-20.

De Bruin, S., Heyns, J. 1992. Dorylaimida (Nematoda) from Botswana. South African Jouirnal of Zoology 27:156-172

Pervez, R., Bilgrami, A.L. 2000. Some factors influencing chemoattraction behaviour of dorylaim predators, Laimydorus baldus and Discolaimus major towards prey kairomones. International Journal of Nematology 10:41-48.

Thorne, G. 1939. A monograph of the nematodes of the superfamily Dorylaimoidea. Capita Zool. 8: 1-263.

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.