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  葉須蟲目是有體節物種,身長從數毫米到超過一米不等。每個體節均有一對槳似的疣足。口前葉一般有一對到兩對眼睛,背部有一對觸角,a ventral pair of sensory palps and a pair of organs on the neck. The peristomium is a ring, often hidden dorsally by the prostomium and the first segment. There is a muscular proboscis with one or more pairs of jaws. The next few segments tend to differ from those further back in having enlarged dorsal and ventral cirri (fine appendages) and reduced parapodial lobes and chaetae (bristles). Some species have appendages with specialised functions but most have many segments that are similar to each other but which vary in size and shape along the length of the body without abrupt changes in the chaetae and parapodia from one to the next.

  本目物種一般皆為捕食性動物或腐食性動物。

  本目的三個主要子群體為:鱗沙蠶亞目(Aphroditiformia)、吻沙蠶亞目(Glyceriformia)及沙蠶亞目(Nereidiformia): There is agreement on the monophyly of a group including the Hesionidae, Nereididae and Chrysopetalidae families but opinions differ about Pilargidae, and molecular and morphological studies continue.

  葉須蟲目原為足刺目之下的一個亞目。後來足刺目升格成為足刺亞綱,其下的葉須蟲亞目亦升格成為葉須蟲目。以下為本目所包含的四個亞目及再之下的各個科:  鱗沙蠶亞目 Aphroditiformia:有文獻把本亞目的分類單元再組成三個總科,但WoRMS質疑這種分類,只列出本亞目之下的科如下: 吻沙蠶亞目 Glyceriformia 沙蠶亞目 Nereidiformia 葉須蟲亞目 Phyllodociformia 亞目地位未定
葉須蟲目(學名:)是多毛綱足刺亞綱之下一個目。這些物種主要在海洋生活,而有少量生活於鹹淡水交界處。本目物種大多數是活躍的底棲生物,在沉積物的表面上移動或在當中挖洞,又或居住在基岩的裂縫和縫隙中。當中有部分物種會建造棲管,又有部分是浮游生物。據估計,約有3500種物種。