No. 1105 / 1 402

Cannonball jellyfish

Stomolophus meleagris

名前について： Its common name comes from its similarity to a cannonball in shape and size. Its scientific name means "many mouthed hunter".1

無害人には無害。心配いらないよ。

クラゲと海の刺す生き物

刺す触手食べもの：肉

人への危険: 軽いハチに刺されたくらいか、それ以下。人にはほぼ無害。

The cannonball jellyfish is a round, dome-shaped jellyfish that looks a bit like a cannonball. It lives in warm coastal waters on both sides of the Americas and in parts of Asia, and it is common in shallow water near the coast. It matters because it is one of the most common causes of minor jellyfish stings in US and Caribbean waters.1

すんでいる場所

Southeastern US coast and Gulf of Mexico, Atlantic from New England to Brazil, Pacific from California to Ecuador, and from the Sea of Japan to the South China Sea1

大西洋, カリブ海, メキシコ湾, カリフォルニア湾

ホーム

They live in shallow inshore waters. On the southeast coast of the United States they are extremely abundant in the summer and fall, when they make up over 16% of the biomass in shallow inshore areas. This is when people are most likely to meet them while swimming.1

長さ

25 cm (9.8 in)1

最高速度

時速約0.7 km（時速0.44マイル）

泳ぐ, おおまかな予想

何を食べるの？

They mainly eat zooplankton, such as veligers, and also all forms of red drum larvae. They catch prey with their oral arms, which also help them move.1

Cannonball jellyfishの写真 — Cannonball jellyfish。写真：Richard Stovall。 CC BY 4.0, iNaturalist.

見分け方

Dome-shaped bell that can reach 25 cm in diameter1
The rim of the bell is often coloured with brown pigment1
A cluster of oral arms under the body, extending out around the mouth1
Some related species found in the Pacific and South Atlantic are pale to blue in colour1

よくまちがえられるのは： Several undescribed Stomolophus species in the Pacific and South Atlantic have pale to blue pigment. They are genetically different from the cannonball jellyfish of the North Atlantic, but they are often misidentified as that species.1

毒パワー

刺す触手

何かがふれると、何千もの小さな刺胞がいっせいに発射されるよ。

その毒（かむ・刺す毒）はどうなるの？

They release a mucus from their nematocysts (stinging cells) that contains a toxin when disturbed. The toxin can cause irregular heart rhythms and problems in the heart's conduction pathways, although this is not common in people. Contact with the nematocysts can be very painful and may cause redness and swelling, and the toxin is also harmful to the eyes.1

人にとってどれくらい危険？

人への危険: 軽いハチに刺されたくらいか、それ以下。人にはほぼ無害。

Cannonball jellyfish are mostly harmless to people. Contact usually causes slight itching or minor eye irritation. They are among the most common causes of minor stings in US and Caribbean waters. Their toxin can cause heart problems in animals and humans, but this does not usually happen.1

こわいとき、どうするの？

When disturbed, they release a toxic mucus from their nematocysts, which harms small fish nearby and drives away most predators.1

刺されたら

水から出て、触手を取りのぞこう（手袋か布を使って）。
熱帯のハコクラゲには：刺されたところに酢を少なくとも30秒かけて、助けを呼び、心肺蘇生（CPR）ができるようにしておこう。カツオノエボシやほとんどのクラゲには：海水で洗い流し、そのあと痛みにはお湯を。

まず必ず救急番号（112、000、911）に電話しよう。これは一般的な応急手当の案内で、医療のアドバイスではないよ。応急手当の基本

安全に過ごそう

野生の動物には、小さくても、ねているように見えても、死んでいるように見えても、ぜったいにさわったり、つかまえたり、からかったりしないこと。
近づかないで。出会ったら落ちついて、ゆっくりあとずさりして、そのまま行かせてあげよう。
刺されたら：落ちついて、じっとして、救急番号（112、000、911）に電話するか、急いで病院へ行こう。見た目をおぼえておいてね。写真があると役に立つよ。

きみをねらっているわけじゃないよ。毒はエサをとったり身を守ったりするために使うだけで、本当はかくれていたいんだ。安全に過ごすためにもっと知ろう

世界のどこ？

アフリカアジアヨーロッパ北アメリカ南アメリカオーストラリアとオセアニア大西洋カリブ海メキシコ湾カリフォルニア湾

どれくらい大きい？

どれくらい長い？

おもちゃのブロック8こを1列にならべた長さ

Cannonball jellyfishは、きみとくらべてどれくらい大きい？

ブラウザで計算しているだけ。何も保存されないし、どこにも送られないよ。

どれくらい速い？

カタツムリ 時速約0.05 km (0.03 mph)

Cannonball jellyfish 時速約0.7 km (0.44 mph)

泳いでいる人 時速約3 km (1.9 mph)

知っておく価値あり

データ

Juvenile portly spider crabs often live in the bell, eating some of the food the jellyfish catches. The jellyfish is not harmed because it can regenerate its tissue. One jellyfish has been seen with up to ten crabs in its bell.1

Jellyfish are commercially harvested as food. In Georgia, jellyball fishing is the state's third largest commercial fishery.1

The endangered leatherback sea turtle is one of their main predators.1

In 2012, El Golfo de Santa Clara in Mexico harvested 20,000 tons of these jellyfish from late April to early July.1

うそ・ほんとう

うそ： Cannonball jellyfish are dangerous to people.

ほんとう： They are mostly harmless to people. Contact usually causes only slight itching or minor eye irritation.1

毒のエキスパート向け

学名: Stomolophus meleagris
グループ: クラゲと海の刺す生き物
家族: Stomolophidae2
ならびかえ: Rhizostomeae
大陸: 大西洋, カリブ海, メキシコ湾, カリフォルニア湾, 海
赤ちゃん: They can reproduce sexually or asexually. Sexual reproduction happens when a cannonball shoots sperm from its mouth and another cannonball catches it. The embryos develop in pouches on the oral arms, then the larvae settle on hard surfaces and grow into polyps.1
人への危険: 1 / 5: 軽い3