SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87b8fb7e677db162e4e41acb9058a40a19d790370bb55be295d0136373eed5e8' 
  AND token = '7c5jYQN+s7l5tnaCs/BJxHd2R55+u2ADTZt83ntgH6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

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