🦠 Morphology and Anatomy

Plant-parasitic nematodes have a simple but highly specialized body organization suited for survival and parasitism. This lesson introduces core external morphology and body-wall anatomy used in identification.

---

General Body Plan

Nematodes are unsegmented, bilaterally symmetrical, and generally cylindrical with tapered ends. Their basic organization is often described as an outer body tube enclosing internal organs.

Morphological characters are central for diagnosis at genus and species level in agricultural nematology.

---

---

Outer Body Tube and Cuticle

The outer body tube includes body wall structures that provide protection, shape, and interaction with the environment. The cuticle (exoskeleton-like covering) is layered and may show taxonomically useful surface patterns.

Common diagnostic features include annulations, punctations, lateral field markings, and longitudinal ridges in specific groups.

---

---

Somatic Musculature

Somatic muscle arrangement is an important anatomical character. Classical patterns include platymyarian, coelomyarian, and circomyarian conditions based on muscle-cell profile and relationship to the hypodermis.

These patterns support comparative morphology and higher-level classification.

---

---

Summary Cheat Sheet

Topic	Key Point
Body symmetry	Bilateral, unsegmented, cylindrical
Structural concept	Outer body tube + internal organ systems
Cuticle role	Protection, support, and diagnostic patterning
Useful markings	Annulations, punctations, ridges, lateral fields
Muscle types	Platymyarian, coelomyarian, circomyarian

Exam focus: cuticle characters and somatic muscle patterns used in nematode identification.

References

1 source • [1]

[1]

Nematode morphology and anatomy notes (PATH172)

Book