ðə ɹɪzˈʌlts ʌv sˌʌm stˈʌdiz sədʒˈɛst ðætðə vˈɛlvɪtfɪʃᵻz ˌɪntʊ ɐn ɛkspˈændᵻd stˈoʊnfɪʃ klˈeɪd, ðə fˈæmɪli sˈɪnɐnsˌiːɪdˌiː bɪkˈʌz ˈɔːl ʌv ðiːz fˈɪʃ hæv ɐ kˈɜːvd sˈeɪbɚlˈaɪk lˈækɹɪməl spˈaɪn ðæt kæn pɹədʒˈɛkt, jˈuːzɪŋ ɐ swˈɪtʃblˈeɪdlˈaɪk mˈɛkənˌɪzəm, ˈaʊt fɹʌm ˌʌndɚnˈiːθ ðɛɹ ˈaɪ.
The results of some studies suggest that the velvetfishes into an expanded stonefish clade, the family Synanceiidae because all of these fish have a curved sabre-like lacrimal spine that can project, using a switch-blade-like mechanism, out from underneath their eye.