Clear Lake splittail
species of fish
The Clear Lake splittail (Pogonichthys ciscoides) is an extinct species of freshwater ray-finned fish belonging to the family Leuciscidae, the shiners, daces and minnows. This species was endemic to California's Clear Lake and its tributaries until its numbers severely declined due to competition from the introduced bluegill and alterations to the flow of inlet streams. In greatly reduced numbers, the Clear Lake Splittail barely persisted until the 1967 introduction to surrounding lakes of the inland silverside as an experiment by the Department of Fish & Game. A fisherman supposedly introduced the silverside via bait bucket into Clear Lake. This dealt the final blow to the Clear Lake splittail, which had similar feeding habits. All of the splittails were taken by fishermen or have been eaten by catfish and large mouth bass. No Clear Lake splittails have been captured since the early 1970s, and the species is presumed to be extinct.
References
NatureServe (2013). "Pogonichthys ciscoides". IUCN Red List of Threatened Species.
Begin with the source’s own compact description: “Clear Lake splittail” is species of fish. The dossier treats that line as a proposition to test through Clear, Lake and splittail, not as a finished interpretation.
Why this record matters
The phrase “species of fish” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
The date and method of observation matter as much as the stated conclusion, especially where classification or consensus has changed. The source revision retrieved here is dated May 21, 2026. The linked authority identifier is Q1104737. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1967 and 2013.
Scientific names, classifications and consensus can change while older terminology persists in catalogues and historical literature. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Check terminology, classification and the date of the cited evidence. Scientific names and technical consensus can change while older records retain historical value.
- Current terminology
- Classification context
- Finding cited technical literature
Primary datasets, specimen catalogues, standards bodies and the most recent peer-reviewed literature.
Three-step research path
- Establish the record: confirm the title “Clear Lake splittail”, its source revision and the description used here.
- Expand the search: follow Clear Lake splittail primary sources, Clear Lake splittail archive and Clear research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Clear Lake splittail”?
- Has classification or technical consensus changed since the cited source?
- Is the terminology current, historical or disputed?
Search terms from this dossier
This entry incorporates text from “Clear Lake splittail” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.