أُمُّ عُوَيْفٍ

A small creeping thing (دُوَيَّبَةٌ), other than the جَرَادَة [which is termed أُمُّ عَوْفٍ]. (TA.)

And, according to AHát, أَبُو عَوْفٍ A species of the [beetles called] جِعْلَان [plural of جُعَلٌ]: it is a small creeping thing (دُوَيْبَّة), dust-coloured, that excavates with its tail and with its two horns, and [then] never appears. (TA.)