Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15fa994b7ff8be39a932b987e602887ca22a44799477a309209f5126a936baa0' 
  AND token = 'sRePYaARGg4nu0htaslzN3PRELmZHqeGG3U5ImW0LAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

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