Karne parah (Hebrew: קַרְנֵי פָרָה, also spelled Qarnei Farah and other variant English spellings) is a cantillation mark found only once in the entire Torah (Book of Numbers Numbers] 35:5), and once in the Book of Esther, immediately following the identically unique Yerach ben yomo.
Dr. David Weisberg suggested[1] that the yerach ben yomo + karne para phrase is meant to call to mind a midrash halakhah, a legal point in Jewish law determined from the verse.
For instance, he claimed[1] that the yerach ben yomo + karne para phrase of Numbers 35:5 is meant to remind the reader of the halakhah that the travel limit on Shabbat is 2,000 cubits, and the Talmud, b. Eruvin 51a derives that distance by analogy from this verse.
The rare trope sound in the Torah appears in Numbers 35:5 on the word B'amah (באמה, cubit), immediately following the word Alpayim (אלפים, two-thousand), on which an equally exclusive Yerach ben yomo is used, on the first of four occurrences of this phrase in the verse.
[3] The yerach ben yomo + karne para phrase occurs a total of 16 times according to the Leningrad Codex.