Development of spiderlings of <i><a href="//commons.wikimedia.org/wiki/Latrodectus_mactans" title="Latrodectus mactans">Latrodectus mactans</a></i> from Cuzco, Peru. 10: After hatching (males and females). 11: After first molt (males). 12: After second and third molts (male). 13: After fourth molt (adult male). 14: After third molt (female). 15: After fourth molt (female). 16 After fourth molt, variant coloration (female). 17: After fifth molt (female). 18: After sixth molt (mature female). 19: After sixth molt, variant pattern (mature female). Molts are counted after leaving egg-sac; there is one molt within egg-sac. White: white; crosshatch: light brown; double crosshatch: dark brow; light stipple: orange; dark stipple: red; black:black. There may be a yellow fringe around the red in areas marked white.
Herbert W. Levi and John D. McCrone, in: Psyche 73:180-186.
CC BY 2.5
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