Two archives, queried live.
Every record below comes from The Met or Smithsonian Open Access and was filtered on that archive’s own rights field before it reached this page. 12 shown for “Oscillatoria cortiana f. tenuior Grunow in Rabenh.” — 40 records examined, 0 dropped by the rights gate.
Archives queried 2026-09-01 22:35 UTC · fetched live for this request
isPublicDomain field is true for this object.metadata_usage.access reads CC0 — a waiver, not an expired term.
Oscillatoria cortiana f. tenuior Grunow in Rabenh.
Artist not stated in the record · Aug 1883

Oscillatoria froehlichii f. tenuior Rabenh.
Artist not stated in the record

Oscillatoria irrigua var. subsalsa Grunow in Rabenh.
Artist not stated in the record · Feb 1861

Oscillatoria terebriformis var. beggiatoriformis Grunow in Rabenh.
Artist not stated in the record

Oscillatoria rubescens var. varesensis Grunow in Rabenh.
Artist not stated in the record · Mar 1852
Oedogonium grande f. tenuior
Artist not stated in the record · 14 Sep 1856

Anabaena bullosa f. tenuior Rabenh.
Artist not stated in the record · 8 Sep 1862

Oscillatoria animalis f. tenuior Stockmayer
Artist not stated in the record · Aug 1893 and Sep 1893

Oscillatoria major f. tenuior Nordstedt in Wittr. & Nordstedt
Artist not stated in the record · 11 Jul 1877

Tolypothrix flaccida f. tenuior Rabenh.
Artist not stated in the record · Aug 1853

Tolypothrix distorta f. tenuior Rabenh.
Artist not stated in the record · Apr 1859

Oscillatoria grateloupii var. tenuior Kütz.
Artist not stated in the record
Where these records came from.
Two archives are wired, and only two. Each one is filtered on its own rights field — never on a title match, and never on the presence of an image file.
- The Met Collection API (Open Access)Rights field:
isPublicDomain. The archive returned no records for this term.0 matched - Smithsonian Open Access API (api.si.edu)Rights field:
content.descriptiveNonRepeating.metadata_usage.access. 7461358 matched · 40 examined · 0 dropped by the rights gate. Kept only where metadata_usage.access === "CC0" and an image resource was published.12 shown
These figures describe the pass run at 2026-09-01 22:35 UTC, during this request. A completed pass is kept for 24 hours and replayed for an identical search, which is what keeps repeated queries inside Smithsonian’s 30-requests-per-hour allowance. A pass in which either archive failed to answer is never kept — an outage must not be replayed as though it were a finding about the catalogue.
Wikimedia Commons and the Library of Congress are deliberately not wired. Wikimedia was confirmed, on a live query, to return CC-BY material inside the same result set as genuine public domain works, and filtering it safely has not been designed yet. loc.gov was blocked by bot detection during the source evaluation, so its rights vocabulary has never been observed — and nothing here is built on a field nobody has read.
An image file is a rights claim. It never travels without its field.