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Thornback guitarfish

Platyrhinoidis triseriata

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionMay 18, 2026
Entity authorityQ137755
Source-derived summary

The thornback guitarfish (Platyrhinoidis triseriata) is a species of ray in the family Platyrhinidae, and the only member of its genus. Despite its name and appearance, it is more closely related to electric rays than to true guitarfishes of the family Rhinobatidae. This species ranges from Tomales Bay to the Gulf of California, generally in inshore waters no deeper than 6 m (20 ft). It can be found on or buried in sand or mud, or in and near kelp beds. Reaching 91 cm (36 in) in length, the thornback guitarfish has a heart-shaped pectoral fin disc and a long, robust tail bearing two posteriorly positioned dorsal fins and a well-developed caudal fin. The most distinctive traits of this plain-colored ray are the three parallel rows of large, hooked thorns that start from the middle of the back and run onto the tail.

Encountered singly or in groups, the thornback guitarfish feeds on small, benthic invertebrates and bony fishes. It is aplacental viviparous, with the developing young drawing sustenance from a yolk sac. Females give birth to 1–15 pups annually in late summer, following a roughly year-long gestation period. The International Union for Conservation of Nature (IUCN) has listed the thornback guitarfish under Least Concern because the majority of its range lies within United States waters, where it is common since it has no commercial value and is not heavily fished commercially or recreationally.

Editorial summary

This brief starts where responsible research should: with the source description of “Thornback guitarfish” as platyrhinoidis triseriata. Everything that follows is an evidence route, not borrowed authority.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current 234-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. The account is most persuasive where Thornback, guitarfish and Platyrhinoidis can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as platyrhinoidis triseriata. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated May 18, 2026. The linked authority identifier is Q137755. None of the 0 selected statements returned an explicit reference.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. 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.

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Source & attribution

This entry incorporates text from Thornback guitarfish” 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.