Pratinema		Contents		Rev: 07/22/2026
		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Pratinema Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Allantonematidae Menu		Feeding		References
		Go to Nemaplex Main Menu		Go to Dictionary of Terminology

Classification:

Chromadorea

Chromadoria

Rhabditida

Tylenchina/Hexatylina

Sphaerularioidea

 Allantonematidae

       Pratinema Chizhov & Sturhan, 1998

Type species: Pratinema sepsis Chizhov & Sturhan, 1998

    Synonyms:
     

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Morphology and Anatomy:

Characteristics of Pratinema sepsis, the type specie,s as an example of genus

 Adult Invasive female.

• Body almost straight. Cuticle finely annulated. lateral field around 3 um wide with six incisures, inner incisures mostly indistinct.
• Cephalic capsule hemispherical without armature but with small circumoral protrusion, continuous with body contour.
• Stylet well developed, with prominent lumen and basal thickenings and mostly asymmetrical; conus about 25% of stylet length.
• Eesophagus narrow, two prominent esophageal glands. DEGO 6-8 um behindstylet base; orifice of subventral 36-40 um behind stylet base. Posterior end of the dorsal oesophageal gland close to mid-body.
• Excretory pore wide; duct wals strongly sclerotized close to pore.
•  Apical cell of gonad 155-220 um from anterior end. Postvulvar sac sometimes present. Vulvar lips equal,
  not protruding, vagina walls slightly cuticularized.
• Tail conically-elongated with slender pointed terminus.

Adult Parasitic female

• Body obese, coiled ventrally in tight spiral. Hypodermis thick, without annulation.
• Cephalic end hemispherical or slightly flattened anteriorl
• Stylet welJ defined, with thin walls and visible lumen, almost no swelling at base. DEGO 6-15 um behind stylet base.
• Cephalic capsule and esophagus reduced. Intestine thick chord-like, filled with granules.
• Ovary with numerous; oviduct narrow and long, usually filled with synchronous eggs
• Vulva opening slit-like, about half of corresponding body diameter.
•  Tail terminus rounded or with digitiform terminus of variable length
• Young parasitic females are oviparous, aged females viviparous.

Free-living male.

• Cuticle finely annulated. Cephalic capsule flatly rounded,
• Stylet small and delicate with prominent basal knobs
• Esophagus structures inconspicuous. DEGO 5-10 um fromstylet base.
• Monorchic, testis 196-270 um long
•  Spicules narrow, slightly broadening to proximal end. No gubernaculum or bursa
• Tail conically-elongated with slightly rounded terminus, often curved dorsally.

Ref: Chizhov and Sturhan, 1998

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Distribution:

Type species described from woodland and lawns near the Sunoshka River in Borok, Russia, associated with flies of the genus Sepsis

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Feeding:

Food Sources and Feeding strategies for the genus Pratinema

Insect-parasitic nematodes in the abdomen of coprophilous flies, genus Sepsis (Diptera)

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Biology and Ecology:

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Life Cycle:

The life cycle of Pratinema, as represented by P. sepsis consists of a single gamogenetic generation with copulation occurring outside the host. The
nematode is localized in the abdomen of the host and an infected fly harbors, generally, one parasitic female and  numerous eggs and juveniles.

The last-stage juveniles migrate from the host through the gonad openings into cow-dung. After 10-15 days they molt tofree-livong males and invasive females.

After copulation the invasive female penetrates the host larvae and oviiposition starts when the young flies leave the cow-dung.

Infected female flies are not completely sterile and can still produce small quantities of fully developed eggs.
Infection of male flies appears to be lethal for the

 At least two generations of the parasite per year have been (Chizhov and Sturhan, 1998).

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Ecosystem Functions and Services:

Regulation of fly populations

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Management:

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References:

Chizhov, V.N. and Sturhan, D. 1998. Pratinema sepsis gen. n., sp. n. (Tylenchida: Allantonematidae), a parasite of coprophilous flies of the genus Sepsis (Diptera: Sepsidae). Russian J. Nematology  6: 5-8.

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Copyright © 1999 by Howard Ferris.
Revised: July 22, 2026.