SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c148bf6d94c752871bf6136f1c27953501b7b7ce8194f22a116d362a8ad768f9' 
  AND token = 'SHNUUxp9EmD4V4HgoMDfJTYYNPgT5cPQuM3k/1JLXqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

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