SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac6834be5e0d8413667cce9260b860dee7b9d3e5a59258176800d43bc238bde3' 
  AND token = 'C8q/oTWRXVXIqMjzmTtjAbLr8O9i3rhB3FJ+uCZJk2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

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