Again, they were only noted recently.
Not having been mentioned in the Bible I believe the traditional religious response has been to write them off to a "separate creation".
Now, regarding "separate creation" what you want to look for are the Church Father's arguments regarding "state of grace". They are quite relevant to the issue at hand. BTW, you have to remember that for about 90% of its history the Catholic Church was pretty much subject to the Creationist Theory, so "separate creation" was a solution regularly proposed to deal with anomalies in that particular theory. Appeals to "modern Church positions" will not help us illuminate this particular debate. My understanding is the "separate creation" and "state of grace" standards for outerspace critters haven't been updated, just abandoned for the time being.
muawiyah - You can talk about this as science all you want but life from outerspace has not been observed. Those little critters still need certain conditions to support life - conditions that have not been proven for outerspace - the hot and cold temperature extremes alone must both be applied due to the extreme cold of outerspace w/ no atmosphere plus the extreme heating they would all be subject too upon re-entry into any planet suitable to support life.
Also I’ve heard of no traditional religious response calling them a ‘separate creation’ - my Bible tells me that God created all creatures - great and small, visible and not visible to the naked eye.