磷沙蚕科

本科物種的若蟲在所有多毛綱的物種來說體型最大[3]，從 0.4 mm 到 2.5 mm不等；有紀錄最大的長達 12 mm; the late stage of an unknown phyllodicid species).[3] Chaetopteridae larvae are barrel-like in form with one to two ciliated bands at the midsection.[3] They also have a large buccal funnel.[3] These larvae are often long lived and effectively disseminate, although are constrained geographically to their appropriate ranges for successful adult growth.[3] The most common form of larval developmental plan for polychaetes is the trochophore larvae.[4] The trochophore will add segments sequentially from a posterior growth zone to produce a nectochaete larva.[4] Chaetopterus represents a distinct deviation from this general design.[4] At no point in larval growth stages does the metatrochophore take on the clearly segmented form of the typical nectochaete larva.[4] The 15 segments of Chaetopterus are formed by subdivision of existing anlage.[4]

The Chaetopteridae have several genera with peculiar and well-studied filter feeding mechanisms. The genera Chaetopterus, Mesochaetopterus, and Spiochaetopterus feed using a thin mucus net suspended across the upper portion of their tube. The mucus net is secreted by a hooplike structure called the aliform notopodia arch. The net can grow at a rate as great as one millimeter per second as water currents generated by the notopodial fans pass plankton through the net. When the net grows large enough it contacts the ciliated cup, which rolls up the net. When the roll becomes large the net is disconnected from the aliform notopodia and is rolled into a ball before the ciliated mid-dorsal groove transports it to the mouth.[2]

本科物種包括下列三個屬：

• 磷沙蚕属 Chaetopterus[1]
• Phyllochaetopterus屬
• Spiochaetopterus屬

另外，分子生物學研究表明，本分類單元是環節動物的基底，位處星蟲動物門之下[5]。

• Some relevant images of adult Chaetopteridae （页面存档备份，存于）