Tergum
- Pronunciation
- /TER-gum/
- Category
- Anatomy
- Singular
- tergum
- Plural
- terga
Definition
The (upper) cuticular plate of an body segment, exclusive of the . In insects and arachnids, each tergum typically consists of one or more sclerotized plates (tergites) that protect underlying musculature and viscera; it articulates laterally with the and ventrally with the sternum. The edge is termed the base, the edge the apex or margin.
Etymology
Latin tergum, 'the back, rear'
Example
In a , the terga of the thoracic segments are expanded into overlapping plates that form the roof of the and provide attachment sites for the powerful muscles.
Synonyms
- tergal plate
- notum (when referring specifically to thoracic terga)
Related Terms
Usage Notes
Tergum refers to the entire region of a segment, while tergite denotes a single hardened within that region; a tergum may comprise multiple tergites. In thoracic segments of insects, the tergum is often called the notum. The adjectival form is tergal. Contrast with sternum () and (lateral).