beautiful lugworm Christmas tree worm

Spirobranchus giganteus, commonly known as the Christmas tree worm, is a tube-building polychaetes worm. The body length is 5-7 cm, and the two umbrella-like gills are called gill caps. The gill crowns, which look like Christmas trees, are used for breathing.The multicolored spirals are highly derived structures for feeding and respiration.The worms’ most distinct features are two “crowns” shaped like Cristmas tree.The Japanese have gill crowns that look like (kanzasi) hairpins, which is a characteristic of the family Crescentidae. Westerners seem to see it as a Christmas tree.

きれいなイバラカンザシは多毛類（ゴカイ類）です。体長は5-7センチメートル、2本の傘のようなものは鰓冠（さいかん）と呼ばれる鰓です。クリスマスツリーのように見える鰓冠は呼吸に使われます。また鰓冠を用いて浮遊生物を捕らえて口に運ぶこともできます。日本人は鰓冠がかんざしのように見え、これがカンザシゴカイ科の特徴です。欧米人はクリスマスツリーに見えるようです。

While diving, you can see the Christmas tree worm on the rocks in the shallows. The red, blue, yellow, and green individuals are beautiful, and their delicate shapes make it hard to believe that they are lugworms(polychaetes worm). You can quickly retract the gill caps by touching them with your fingers. the Christmas tree worm is among tube-building polychaetes worm. It lives a permanent life in a tube, and its body length is 5 to 7 centimeters. The living tube is made of calcareous material. The habitat tube is completely embedded in the habitat, so it is possible to hide the entire body by retracting the body inside. Individuals have been collected to determine their age, and it has been found that most of them are around 10-20 years old, which is about the same lifespan as dogs and cats.

ダイビングしていると浅瀬の岩でカンザシゴカイを見ることができます。赤、青、黄、緑などの個体は美しく、これがゴカイとは思えない繊細な形が魅力的です。指で触ると鰓冠を素早く引っ込めることができます。イバラカンザシは棲菅（せいかん）ゴカイのなかまです。定住場所となる管（チューブ）のなかで定住生活をして体長は5-7センチメートル。棲管は石灰質でできいます。棲管は定住場所に完全に埋め込まれているので、体をの中に引っ込めると体全体を隠すことが可能。個体を採取して年齢が調べられたことがあり、それによると10-20年程度のものが多く犬や猫と同じくらい長生きです。