Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_15417439_1 (length VARCHAR, genus_species VARCHAR)

### Question ###
For the genus/species arabidopsis thaliana, what are the lengths? 

### Accurate SQL ###

SELECT length FROM table_15417439_1 WHERE genus_species = "Arabidopsis thaliana"