SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd75bfa5754db46cb4ac6b1c29fb55b9a30fa9d38a127eed2fffb72a748070360' 
  AND token = 'gurQhPTGHxIjNV42I4VIglnwfvoHmH70C4OtBpkShlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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