SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5acdb9a370c361850fd0ddbd5f7d93b7c2129b54a3f84a235745f2a8c4a4c367' 
  AND token = 'mIgsDUxgS8L92LM11Bti4wcpMPoou+AwiLSmTib6gDI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

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