Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef35439d349b51a453b02cac56693c3ce8e696baa3131eac7f811beeefd2c289' 
  AND token = 'FI0bVmY7DpPcPy6UC7Mn725mp28YdykGKt0B3f89Mxg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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