Tarsal formula
Appearance
![](http://178.128.105.246/cars-http-upload.wikimedia.org/wikipedia/commons/thumb/3/30/InsectLeg.png/220px-InsectLeg.png)
The tarsal formula is the number of segments on the tarsi of arthropods. The tarsus is the bottom part of an arthropod's legs, see diagram.
The formula has 3 numbers a-b-c, starting with the front leg (a), then the middle leg (b), then the hind leg (c). For example, a tarsal formula of "5-5-4" means there are 5 segments in the fore leg's tarsi, 5 segments in the middle leg's tarsi, and 4 segments in the hind leg's tarsi.[1] This character is especially useful at family rank and higher.[2]
The characteristic is useful when identifying insects.
References
[change | change source]- ↑ Waterbug key. [1] Archived 2014-03-10 at the Wayback Machine
- ↑ "tarsus, tarsi, tarsomere, tarsal formula - BugGuide.Net". bugguide.net.