第 1109 號，共 1 402 號

Upside-down jellyfish

Cassiopea andromeda

無害對人無害。不用擔心。

會螫人的觸手吃：肉

The upside-down jellyfish is a jellyfish that usually rests with its mouth facing up, so it can look more like a sea anemone. It lives in shallow, sheltered coastal water, such as lagoons and mangrove areas. It is special because it shares a partnership with algae that give it colour and food.1

分布在

Shallow coastal waters around mangroves, lagoons, and intertidal sand or mudflats1

印度洋, 太平洋, 紅海, 地中海, 帝汶海與阿拉弗拉海, 孟加拉灣

首頁

It usually lives on intertidal sand or mudflats, in shallow lagoons, and around mangroves.1

長度

30 cm (1 ft)1

最高速度

大約 0,7 km/h（0,44 mph）

游泳, 粗略估計

牠吃什麼？

It eats small animals from the sea, or pieces of them. It first paralyses its prey with its mucus and nematocysts, which are stinging cells.1

Upside-down jellyfish 的照片 — Upside-down jellyfish。照片：prilfish。 CC BY 4.0, iNaturalist.

怎麼認出牠

Yellow-brown bell with white or pale streaks and spots1
Usually keeps its mouth facing upward1
Bell pulses to move water through its arms1
Can grow up to 30.0 cm wide1

常被誤認為： It is often mistaken for a sea anemone. Its usual upward-facing mouth and pulsing bell are features to note.1

毒液力量

會螫人的觸手

有東西碰到時，成千上萬個小小的刺細胞就會發射。

牠的毒液有什麼作用？

Its stinging cells, called nematocysts, release venom that paralyses small prey. In people, a sting causes mild pain, a rash and swelling.1

牠對人有多危險？

對人的危險: 輕微跟蜜蜂螫差不多或更輕微。對人基本上無害。

Its sting is painful, but the symptoms described are mild.1

如果牠螫人

離開水裡，把觸手拿掉（戴手套或用布）。
熱帶箱形水母：在螫傷處倒醋至少 30 秒，求救，並準備好做心肺復甦術（CPR）。藍瓶水母和大多數其他水母：用海水沖洗，再用熱水止痛。

一定要先打緊急電話（112、000、911）。這是一般急救指引，不是醫療建議。急救基本知識

注意安全

絕對不要碰、抓或捉弄野生動物，就算是很小的動物，就算牠看起來在睡覺或已經死了也一樣。
給牠空間。如果遇到了，保持冷靜，慢慢往後退，讓牠自己離開。
如果被牠螫了：保持冷靜，保持不動，打緊急電話（112、000、911）或趕快去醫院。記住牠的樣子，有照片會很有幫助。

牠不是想來抓你。牠用毒液來捕捉食物或保護自己，而且牠更想躲起來。更多安全知識

在世界上的哪裡？

非洲亞洲歐洲北美洲南美洲澳洲與大洋洲太平洋印度洋地中海紅海帝汶海與阿拉弗拉海孟加拉灣

牠有多大？

牠有多長？

跟 9 塊玩具積木排成一排一樣長

Upside-down jellyfish 跟「你」比起來有多大？

只是在你的瀏覽器裡做算術。什麼都不會儲存，也不會傳送到任何地方。

牠有多快？

一隻花園蝸牛 大約 0,05 km/h (0,03 mph)

Upside-down jellyfish 大約 0,7 km/h (0,44 mph)

一個正在游泳的人 大約 3 km/h (1,9 mph)

值得知道

小知識

It is a jellyfish, even though it is often mistaken for a sea anemone.1

A shrimp lives among its tentacles and removes parasites from it. In exchange, the jellyfish protects the shrimp.1

Tiny algae called zooxanthellae live in its tissues, giving it its colour. In return, the jellyfish gives the algae the sunlight they need.1

It can reproduce both by budding, when it is in its polyp form, and sexually, when it is in its medusa form.1

Its pulsing bell moves water through its arms, which helps it breathe and gather food.1

破解迷思

迷思： It is a sea anemone.

真相： It is a jellyfish, a type of cnidarian, although it is often mistaken for a sea anemone.1

給毒液專家

學名: Cassiopea andromeda
類群: 水母和會螫人的海洋生物
家人: Cassiopeidae2
排序: Rhizostomeae
各大洲: 印度洋, 太平洋, 紅海, 地中海, 帝汶海與阿拉弗拉海, 孟加拉灣, 海洋
寶寶: The medusa female produces eggs and keeps them. The female uses her tentacles to catch sperm from the water to fertilise the eggs.1
對人的危險: 1 / 5: 輕微3