Phylum Nematoda

Rev. 08/24/2021

Class Enoplea
            1. amphids pocket like, not spiral, usually post-labial.
            2. cuticle smooth or finely striated.
            3. phasmids present or absent.
            4. esophagus cylindrical or bottle-shaped with 3 to 5 esophageal glands, stichosome or trophosome may be present.
            5. simple non-tubular excretory system, usually a single cell.
            6. female generally with two ovaries.
            7. male generally with two testes.
            8. caudal alae rare.
Sub-class: Enoplia
  1. inner labial sensillae papilliform, outer labial and cephalic sensillae setiform
  2. Stoma variable, often with teeth which are sometimes moveable (e.g., Triplonchidae - Diphtherophorina)
  3. Esophagus cylindrical, sometimes enlerged posteriorly (e.g. Triplonchida - Trichodoridae).
  4. Esophageal glands open in or near stoma.
  5. Caudal glands usually present
  6. mainly free-living, ecept Trichodoridae
                      Order 1.  Enoplida - marine and brackish water, feed on diatoms, algae etc.
                           a) marine, brackish water, and soil inhabitants.          
                           b) excretory cell not seen, have hypodermal glands.
                           c) no head setae.
                           d) male with delicate supplements.
                           e) esophageal glands open in or near stoma
 f) caudal glands present.
                                                g) spicule protractor muscles inserted in manubrium, not as a capsule surrounding spicules.
Order 2.  Triplonchida  - movable tooth.  Trichodoridae  are plant parasites and vectors of plant viruses.
a) soil inhabitants, rarely freshwater.          
                                                b) excretory cell not seen, have hypodermal glands.
                                                c) no head setae.
                                                d) male with delicate supplements.
                                                e) esophageal glands open in or near stoma
f) caudal glands restricted to tail if present
g) spicule protractor muscles as a capsule surrounding spicules.
Sub-class: Dorylaimia (from Greek - "spike throat")
  1. anterior sensillae usually not setiform
  2. Stoma with tooth or moveable odontostyle moveable
  3. Esophagus cylindrical, bottle-shaped, or even vestigial and represented as a stichosome
  4. Esophageal glands usually open behind nerve ring
  5. Caudal glands usually absent
  6. Free-living in freshwater and soil, parasites of vertebrates and invertebrates and of plants (Longidoridae).
Order 1.  Dorylaimida - movable mural tooth or hollow spear.  All soil or freshwater inhabitants, no marine.  Longidoridae are plant parasites and vectors of plant viruses.
Sub-order Dorylaimina
             a) Stoma with odontostyle 
Superfamily 1:  Dorylaimoidea
Superfamily 2:  Belondiroidea
Superfamily 3:  Tylencholaimoidea
Sub-order Nygolaimia (from Greek - "pricking throat")
             b) Stoma with grooved subventral tooth 
Superfaimly 1:  Nygolaimoidea
Order 2.  Mermithida  multiple glandular esophagus - stichosome- invertebrate parasites, e.g., Mermis, Romanomermis.
Sub-order Mermithina
Superfamily 1:  Mermithoidea
Order 3.  Mononchida - strong, cuticularized stoma, predaceous and cannibalistic. Soil and freshwater, no marine.
Sub-order Bathyodontina
Superfamily 1:  Cryptononchoide
Superfamily 2:  Mononchuloidea
Sub-order Mononchina
Superfamily 1:  Anatonchoidea
Superfamily 2:  Mononchoidea
Order 4.  Dioctophymatida - parasites of birds and mammals; intermediate hosts are oligochaetes or both oligochaetes and fish
Sub-order Dioctophymatina
Superfamily 1:  Dioctophymatoidea
Order 5.  Trichinellida - multiple glandular esophagus - stichosome- vertebrate parasites, e.g., Trichinella spiralis  (trichinosis)
                                    Trichuris (whip worm)
Sub-order Trichinellina
Superfamily 1:  Trichinelloidea
Order 6.  Isolaimiida- long and slender, soil inhabitants, probably bacterivores
Sub-order Isolaimii009)na
Superfamily 1:  Isolaimioidea
Order 7.  Muspiceida - parasites of mammals e.g. Lukonema, parasite of bats.
Sub-order Muspiceina
Superfamily 1:  Muspiceoidea
Order 8. Marimermithida - parasites of deep-sea bottom-dwelling invertebrates.
Sub-order Marimerthina
Superfamily 1: Marimermithoidea - 

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