---
title: "List the provenance facts of a species"
method: GET
path: "/api/v1/species/{id}/facts"
tags: ["Species"]
---

# List the provenance facts of a species

`GET /api/v1/species/{id}/facts`

Every sourced claim about this species' trait values, including superseded and rejected ones. The species trait columns are a projection of the strongest active fact per attribute; this endpoint is the trail behind them.

## Path parameters

- `id` string, required

## Response `200`

Success

- object
  - `data` SpeciesFact[]
    - `attribute_name` string, required — The species attribute this claim is about (ex: `average_height_cm`)
    - `source` string, required — The source making the claim (ex: `powo`, `try`, `gbif`)
    - `value` string, nullable — The claimed value, as a string
    - `unit` string, nullable — The unit of the value, when the attribute carries one
    - `evidence_type` 'reported' | 'measured' | 'derived' | 'inferred', required — How the claim is backed. `reported`: asserted by an external database. `measured`: backed by referenced measurements. `derived`: computed by us from primary data. `inferred`: imputed, ex: from congeneric species.
    - `status` 'active' | 'superseded' | 'rejected', required — `active`: the current claim from this source. `superseded`: replaced by a newer claim from the same source. `rejected`: failed plausibility validation and was never applied.
    - `notes` string, nullable
    - `source_record_id` string, nullable — The identifier of the record at the source
    - `source_url` string, nullable — A link to the record at the source
    - `n_observations` integer, nullable — Number of underlying observations, for measured facts
    - `observed_at` string, nullable
    - `updated_at` string, nullable
  - `meta` object
    - `total` integer

## Other responses

- `401` — Invalid credentials

## Changes

- **2026-09-15** (v1) `bc4139bd950e` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/treflehq/apis/trefle-api-v1/changes/api/v1/species/:id/facts/get.md)

---

[API](https://skmtc.dev/treflehq/apis/trefle-api-v1.md) · [All operations](https://skmtc.dev/treflehq/apis/trefle-api-v1/llms.txt) · [OpenAPI document](https://skmtc.dev/treflehq/apis/trefle-api-v1/revisions/02782b5979dc?raw)