## Problem 314 — rank:316

**Title:** How many species exist?

**Added binding assumptions (LaTeX):**

```latex
Specify a genuine equivalence relation for the counted taxonomic units and the treatment of uncertain split/merge assignments. If arbitrarily many species may have zero detection probability, adding them leaves the observed law unchanged; without a positive detection lower bound, arbitrarily small detection probabilities also defeat uniform informative upper bounds. These are identifiable-model obstructions, not unsolved counting theorems. The research target is defensible tail restrictions and efficient survey design.
```

**Direct edits:** 0. **Fresh external checks:** None; supplied sources retained as provenance.