# The mamenchisaurid locality review

The earlier 19-member branch is a missing-metadata outcome, not a recorded Daye assemblage. A Tibet/Xizang locality clue is sufficient in this comparison. If a geological unit is displayed, scope it by province.

| Target | Explicit proposed clue | Earlier country-only maximum | New maximum after every reaching guess |
| --- | --- | ---: | ---: |
| Damalasaurus | Tibet / Xizang · China | 34 | 2 |
| Microdontosaurus | Tibet / Xizang · China | 34 | 2 |
| Damalasaurus | Daye Group · Tibet / Xizang · China | 34 | 1 |
| Microdontosaurus | Chaya Group · Tibet / Xizang · China | 34 | 1 |

All 19 genera and 32 captured occurrences were reviewed. Four clue comparisons for two targets were checked against 1224 reaching-guess contexts, with wider descendants and missing standard facts retained.

Remaining mamenchisaurid possibilities: none in the reviewed comparison. The recommended province-only clue leaves Damalasaurus and Microdontosaurus; finer unit + province wording leaves one. These are roster-comparison counts, not hidden-answer approvals.

The 18 genera with their own supported locality comparisons were also rechecked against the reviewed footprints. 0 exceed five after their locality and reaching guess. Zigongosaurus has no supported hidden-target comparison.

## Decisions

- Prefer Tibet/Xizang, China as the first locality support for these two targets: it narrows the reviewed comparison without immediately naming a unique unit. If a unit is displayed, include Tibet/Xizang explicitly. A blank group field on a recorded fossil elsewhere does not make its geographical origin unknown.
- Correct the earlier explanation: Microdontosaurus uses Chaya Group, not Daye Group. The place name Daye in its collection label must not be converted into a geological-group match.
- Attach sourced geography to 12 existing literature-summary rows in this review overlay. All raw occurrences, qualified referrals and supported horizon alternatives remain available; no parent-group memberships are invented.
- Keep the country-only assessment as a checkpoint. This follow-up supersedes its two target comparisons with explicit provincial support and also tests finer unit + province wording; no discovery-date clue is required for these count results.
- Retain all 19 genera as legal source guesses under the existing roster policy. This locality review does not approve additional hidden answers or resolve contested genus identities.

## Historical unit names

- Daye is a historical Jurassic locality/unit name in Qamdo, eastern Tibet. McPhee2016 uses Daye Group/Duogaila member; Wei2023 uses Daye Formation for the historical material. Preserve these different rank usages rather than silently renaming the frozen specimen horizon.
- Modern Qamdo schemes are not a verified specimen-level crosswalk for Damalasaurus or Microdontosaurus. Do not equate Daye, Chaya, Dabuka/Dapuka or Dongdaqiao across every record merely because their terminology overlaps.
- Microdontosaurus record1252925 explicitly has Chaya group, with formerly Dabuka Formation in comments and Daye as part of the locality name. Original Zhao1985 naming account remains unread.
- The geographical clue is supported at Tibet/Xizang level. No unsupported finer quarry or constituent formation is required to resolve this comparison.
- Xinjiangtitan retains Qiketai/Qigu alternatives from competing primary accounts. Qijianglong retains Suining/Upper Shaximiao alternatives; the later remapping is explicitly unpublished. Neither conflict moves those specimens to Tibet.
- Zigongosaurus has no captured genus-linked occurrence. A primary historical Wujiaba/Sichuan locality account resolves geography of its existing literature summary, but its identity and standard clues remain unapproved.
- Omeisaurus preserves all thirteen captured records. The type row combines Shaximiao Formation with Daanzhai member; that potential horizon inconsistency needs a separate specimen-level review. Its Gansu blank-horizon and qualified Guangyuan records remain intact.

## Every genus checked

| Genus | Captured occurrences | Captured provinces | Named-genus Daye / Chaya evidence |
| --- | ---: | --- | --- |
| Analong | 1 | Yunnan | No positive match found; unknowns retained where relevant |
| Anhuilong | 1 | Anhui | No positive match found; unknowns retained where relevant |
| Bellusaurus | 1 | Xinjiang | No positive match found; unknowns retained where relevant |
| Chuanjiesaurus | 1 | Yunnan | No positive match found; unknowns retained where relevant |
| Daanosaurus | 1 | Sichuan | No positive match found; unknowns retained where relevant |
| Eomamenchisaurus | 1 | Yunnan | No positive match found; unknowns retained where relevant |
| Huangshanlong | 1 | Anhui | No positive match found; unknowns retained where relevant |
| Hudiesaurus | 1 | Xinjiang | No positive match found; unknowns retained where relevant |
| Jingiella | 1 | Guangxi Zhuang | No positive match found; unknowns retained where relevant |
| Klamelisaurus | 1 | Xinjiang | No positive match found; unknowns retained where relevant |
| Omeisaurus | 13 | Chongqing, Gansu, Sichuan | No positive match found; unknowns retained where relevant |
| Qijianglong | 1 | Chongqing | No positive match found; unknowns retained where relevant |
| Rhomaleopakhus | 1 | Xinjiang | No positive match found; unknowns retained where relevant |
| Tienshanosaurus | 3 | Xinjiang | No positive match found; unknowns retained where relevant |
| Tonganosaurus | 1 | Sichuan | No positive match found; unknowns retained where relevant |
| Tongnanlong | 1 | Chongqing | No positive match found; unknowns retained where relevant |
| Xinjiangtitan | 1 | Xinjiang | No positive match found; unknowns retained where relevant |
| Yuanmousaurus | 1 | Yunnan | No positive match found; unknowns retained where relevant |
| Zigongosaurus | 0 | No genus-linked occurrence; see literature | No positive match found; unknowns retained where relevant |

## Limits

- Every captured occurrence for these 19 genera was inspected, including 13 Omeisaurus records, qualified identifications and its blank-horizon Gansu record. Targeted primary literature review is not proof of exhaustive fossil absence; new credible Tibetan occurrences must be added and can change the result.
- Exact geographic amendments apply to identified existing summaries, not to whole-genus ranges or independent future fossils. Omeisaurus summary possibleStates preserves uncertainty and creates no positive occurrence.
- Some original descriptions were inaccessible; each dossier records full-text versus abstract access and unresolved original specimen/age issues.
- Counts use the frozen source tree, all three provisional standard clues and every wrong guess reaching the target parent. They do not certify the future Expert tree, every possible game history or hidden-answer readiness.
- The live 36-genus sample remains unchanged. These source-review clue proposals and geography overlays are documented for the expanded roster; they are not newly activated game clues.

Reproduce with `python review-mamenchisaurid-localities.py`. Full specimen and source-access dossiers are preserved under `audits/2026-10-10-mamenchisaurids/`.