Entire hair (type 2) with inset showing end normally loosely attached to spider. Total length ca. 210um (0.210mm). Microscope magnification x440.
	Detail of barbed distal end. Magnification ca. x2,400
	Part (ca. 1/5th ) of type 1 hair showing coarse barbs along its full length. Magnification ca. x570
	Detail of barbed distal end of type 1 hair. Magnification ca. x3,100

Tarantulas are known for being large, hairy spiders with powerful fangs, a venomous bite and an appetite for birds and mice.

A less obvious attribute against themselves being preyed upon is found amongst the hairs of their abdomen.

When alarmed, Tarantulas rub their hind legs over their abdomen to dislodge a cloud of fine hairs into the path of an oncoming aggressor. Each of the myriad of hairs has a barbed, needle-sharp tip that pierces and lodges in the skin and eyes causing severe irritation and efficiently deterring a prolonged assault.

Two types of urticating hair are found on the Mexican Red-Knee Tarantula. Type 1, 1mm long with coarse barbs along its full length and type 2, just 0.2mm long, very ornate but equally as unpleasant.