That would be a condition - worthy of preservation.
Inherent value says all conditions being equal… In your example, the worthy/unworthy of preservation would have to equal out.
So the question is: if were equally worthy and unworthy of preservation, ought you kill it? Or flip a coin, because there's no value to either decision?
Or would your values be to let it live unless you had a good reason not to?
like anything else.
Like a rock? Life/Rock, same thing, same inherent value?
If life has inherent value, it's not a coin toss question, you don't need a reason not to kill it, you need a reason to kill it.
Which is it for you?
All things are never equal. One would have to conduct a scientific experiment every time one were to make a decision to make sure.
There is also a middle "I don't care either way" category, which means you walk away from the dilemma. But many people become slaves of their either-or dungeon.
For example, Muslims have a nasty and odious habit (there is so much odious about them, come to think of it!) of killing their daughters and sisters if they think they "dishonored" the family (honor killings). This is a perfecter example of a moralistic religious dungeon so many humans can sink into.
The Golden Rule is applicable here too. Ask yourself if you were the subject to be decided on, which course of action wold you prefer. We choose life, because we value life (for ourselves) and because it is inhernely obvious that every living thing on this earth is a citizen of this planet and has a right to be here, their life is equally valueable to them. So, live an dlet live.
Like a rock?
Rocks are not alive. But we eed innanimate obects as well. Wanton destruction is harmful, and that which harmful is a "feels-bad" and we tend to avoid it. Living things avoid danger, whether they are flatworms or humans. It's an atavistic part of our evolved nature to preserve ourselves. We should only extend that to others if we think we deserve it too (Golden Rule again).
If life has inherent value, it's not a coin toss question, you don't need a reason not to kill it, you need a reason to kill it. Which is it for you?
We need a reason for everything we do. Otherwise we do nothing. Killing veerything in sight is counterproductive unless it represents reflief from immediate danger to you. It all comes down to feels-good, feels-bad decision approach to life that we know from infancy. It's simple approach/avoidance.