With most sponges filtering food out of the water, I am utterly mystified by the group of deep-sea carnivorous sponges. https://watermark.silverchair.com/j.1096-3642.2006.00234.x.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAswwggLIBgkqhkiG9w0BBwagggK5MIICtQIBADCCAq4GCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQM3dUTGCBF8SVQn_JnAgEQgIICfwkAYkAjkcMHnQ6rASbFO94PpXgjSmmPGw3VJaJMX11rPSsIsUXcnZwdee96q0AuxySmmGncOQjM1HiBF5mCSywUA38I6YBEuBYxevevxcFEqQplI_fCen05wFd-LGRNbs6MsOkk5t5FQJE7IwtzCqh_P2Cb7mdH_OXwXBL7sEKZLpTbIJttGoJKvqVSlrbVi8_1JCdXFodxZEIkgUXmjn-DfE9VkCK3i7Cr8_M59gOLR-LZcHpC6tHWwbO-oEDTEJ4q4WVp5Qco9dDFp_eEODkrjpTcXC1V79exXDh_6A8-mnmWPW8Vz_wYHLlmz3glLJqucOlOtdT6CpJiytH23W8B5ejivGSP0vFlrjYeH0MgurSCMvQ1YQtTh-abmFGPAxMcxATtz9i5kf51WpR3IMsQFGLDtz_fBB8MwPqitkAoWZzwoK5TrBK8m-O4C4QDD58CoxIHYbmssfiHUmCQ1lhrjZFqndiyfjLmXAVGMKwGz43yox1ZBZOiWCsYWZnoj2Xvegw7O6nkQ-JySH3gmsn6bfWS-CUeTe_oL8ErFh28Hd_wmq7TZEu2Lo5FeDWATPRI64MLbgYUmMI7DEJQBYxEu-mRfw4OmutxmKHlI9CBQm4rAnelZw1k8DuUV-q5rz7phTC81B0tfCuRRA7r4hfbXLZtK0Icc2hVnzdKfARAcipP1_xb6_9LrKCujirtXEuS44fIELd4I8Zd0XKNciRpRxU3N06K471HFXDbAH15IRbaSvocrmHIJW1r6QSVMACH3Bx1tA7aJ-qlUqkAtmMXMfnWZjlUAS84KfE4ieBNYt3zcNJm6VWSsACxuVj0JEB1TfNqQqC1y8duONgihw

They have modified spicules, silica rods, shaped like hooks. These cover the sponge and working like velcro ensare little crustaceans.

Once a crustacean is trapped, the sponge covers it with a layer of sponge cells and digests it. It would be like a mosquito landing on your arm, getting caught in your arm hairs,and you grow a layer of skin over it to digest it.

The beautiful carnivorous sponges also take on amazing forms. Chondroclaia lampadiglosa look like a lollipop tree Image from http://chess.myspecies.info/file-colorboxed/693

Also take a look at the harp sponge described by scientsist at @MBARI_News Image is from MBARI https://www.mbari.org/scientists-discover-extraordinary-new-carnivorous-sponge/