SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '083b181a678494b81a5c00311630b56f2120fd30d09efeb5feae55ba971b13ac' 
  AND token = '/SiIMihQ+Y5kqrmm3OvIcv7dCG8BVa7kwH5TR0YPsT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

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