Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ebeb31695039536c17b9ca7c395ad0d02c11fc377e8ea4025c6680ad80b7e6c' 
  AND token = 'E8QlmDJ76qvTC7KFUIFB1e8CdwlhqxZlLpU9Lp9mFH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

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