Basic anatomical features

Tylenchulus semipenetrans: citrus nematode

Size and shape comparisons

Size comparison

Dagger nematode: Xiphinema sp.

Stubby-root nematode: Paratrichodorus sp.

Reniform nematode: Rotylenchulus reniformis

Ring nematode: Mesocriconema xenoplax

Feeding apparatus: Meloidogyne hapla

Feeding apparatus: Panagrolaimus sp.

Feeding apparatus: Cruznema sp.

Feeding apparatus: Trichodorus sp.

Feeding apparatus: Meloidogyne incognita

Feeding apparatus: Xiphinema sp.

Feeding apparatus: Tylenchus sp.

Feeding apparatus: Belonolaimus sp.

Sensory structures: Desmodora pilosa

Sensory structures: Xiphinema sp.

Sensory structures: Scutellonema sp.

Characteristics of generalized male and female nematodes

Early line drawing of morphology and anatomy

Adult female root-knot nematode, Meloidogyne sp., (left), adult female spiral nematode, Helicotylenchus sp., (right).

Adult female root-knot nematode on head of pin.

Vermiform and motile adult.

Vermiform and motile adult

Sedentary adult female, swollen on outside of root.

Thick cuticle with deep striations to allow flexibility.

Protrusible, hollow, stomatostyle.

Open stoma for ingesting bacteria.

Open tubular stoma for ingesting bacteria.

Curved onchiostyle with dorsal groove.

Electron micrograph of anterior surrounded by feeding site.

Long odontostyle and extension for feeding deep into root tip cells without entering root tissue.

Small, delicate stylet. Feeding habit uncertain but possibly root hairs or algae.

Valved metacorpus; pumping structure in esophagus.

Spiral openings to chemosensory amphids on either side of head.

Slit-like openings to chemosensory amphids on either side of lip region.

Enlarged phasmid, termed scutellum in this genus. Sensory structures in lateral field on either side of posterior region of body.