Paroctonchus		Contents		Rev 08/29/2026
		Classification		Hosts
		Morphology and Anatomy		Life Cycle
Return to Paroctonchus Menu		Economic Importance		Damage
		Distribution		Management
Return to Oncholaimdae Menu		Feeding		References
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Classification:

Enoplea

     Enoplia

        Enoplida

          Oncholaimina

              Oncholaimoidea

                    Oncholaimidae

    Octonchinae

Paroctonchus Shi & Xu, 2016

Type species of the genus: Paroctonchus nanjiensis Shi & Xu, 2016

Synonyms:

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Morphology and Anatomy:

• Distinct in the family Oncholaimidae in having more than three teeth, a character which also occurs in the monotypic genera Octonchus and Patagonema of the subfamily Octonchinae.
• Number and arrangement of teeth in the buccal cavity in Paroctonchus: three large teeth with the left ventrosublateral one the largest plus about 27 small teeth distributed on the wall. By contrast, Octonchus has one large tooth plus eight small teeth, while Patagonema has three large teeth with the right ventrosublateral one the largest plus 12 small teeth on three mandibular ridges.
•  Paroctonchus nanjiensis differs from Octonchus in having the amphid aperture(located in the middle portion of buccal cavity vs. at the base of buccal cavity, and from Patagonema in the absence of a demanian system  and the presence of two subventral rows of wart-like precloacal supplements vs. a ventral row of papillate supplements.
• Posterior end of buccal cavity surrounded by a pharyngeal collar.
• Amphidial fovea pocket-like with transverse slit-like aperture in middle portion of buccal cavity.
• Cardia conspicuous and conical.
• Demanian system absent.
• Tail conical-cylindrical

Male:

• Diorchic, testes outstretched
• Spicules short and straight, without gubernaculum.
• Precloacal supplements present.

Female:

• Didelphic, ovaries reflexed

Ref: Shi and Xu, 2016; Huang and Guo, 2022

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Distribution:

Type species described from intertidal sediments in a sandy beach in the China Nanji Islands Natural Reserve in the East China Sea.

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Economic Importance:

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Feeding:

Food Sources and Feeding strategies for the genus Paroctonchus

     Omnivores?

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Life Cycle:

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Damage:

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Management:

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References:

Huang, Y. and Guo, Y. 2022. Free-living Marine Nematodes from the East China Sea, https://doi.org/10.1007/978-981-16-3836-7_10

Shi, B., Xu, K. 2016. Paroctonchus nanjiensis gen. nov., sp. nov. (Nematoda, Enoplida, Oncholaimidae) from intertidal sediments in the East China Sea. Zootaxa 4126:097-106

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Revised by Howard Ferris: August 29, 2026.