SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2115c81185af9959c19b617a2dfb7bacfc524daa37d68f821692ccdc308ea02' 
  AND token = '14lCjWkdDLsHk3eB7cwoaF+oDBWnFg23LbzkhvU9l2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables