Arachnodactyly

Arachnodactyly, also known as "spider fingers" or achromachia, is a condition in which the fingers are abnormally long and slender in comparison to the palm of the hand. It can be present at birth or develop in later life.This feature can occur on its own, with no underlying health problems. However, it can also be associated with certain medical conditions. Examples include Marfan syndrome and homocystinuria.Arachnodactyly has been linked to mutations in the fibrillin-2 gene.
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Arachnodactyly /arach·no·dac·ty·ly/ extreme length and slenderness of fingers and toes. a·rach·no·dac·ty·ly n. [more]Arachnodactyly - Community and Resources

Long spider-like fingers and toes.

DOLICODATTILIA