SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe4d89dda6d58c81251b96639cf77a20dc71b884fac721190d5a5ca400999abc' 
  AND token = '91DDXW5edJwUZ5/K2ouDQ0pXN50Jt/0N6ix02eQirwU=' 
  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