Sidymella is a genus of spider in the family Thomisidae, found in South America, Australia and New Zealand. It was originally named Sidyma, but this was later found to have been used already for a genus of moths.

The genus was first erected by Eugène Simon in 1895 under the name Sidyma, with the type species Sidyma lucida. However, it was later discovered that there was a moth genus Sidyma, named in 1856, so the genus name was preoccupied. The replacement name Sidymella was provided by Strand in 1942.