第 0584 號，共 1 402 號

Western hognose snake

Heterodon nasicus

名字的由來： "Hognose" comes from its upturned nose, which looks hog-like. The scientific name nasicus comes from the Latin nasus, meaning "nose".1

無害對人無害。不用擔心。

後毒牙蛇

咬吃：肉

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。

The western hognose snake is a small, stout-bodied snake with an upturned nose that looks a bit like a pig's snout. It lives across much of North America, from southern Canada to northern Mexico, in sandy and gravelly places such as prairies and grasslands. It is often mistaken for a rattlesnake, but its bite is not regarded as dangerous to people.1

分布在

Southern Canada, through the United States, to northern Mexico. Endemic to North America.1

北美洲

首頁

It favours areas with sandy or gravelly soils, including prairies, river floodplains, scrub, grasslands, semi-deserts and some semi-agricultural land. It has been found at elevations of up to 2,500 m (8,200 feet).1

長度

13 cm 到 50 cm (5,1 in 到 1,6 ft)1

最高速度

大約 4,7 km/h（2,9 mph）

在陸地上, 粗略估計

牠吃什麼？

It mainly eats amphibians, such as large and medium tree frogs, small or medium toads and small lizards, and occasionally a rodent. It is not a true constrictor, so it bites and chews, driving its rear fangs into prey.1

Western hognose snake 的照片 — Western hognose snake。照片：Peter Paplanus。 CC BY 4.0, iNaturalist.

怎麼認出牠

Relatively small and stout-bodied, with adults rarely exceeding 40–50 cm in total length, tail included.1
A modified, upturned nose scale gives it a distinctive hog-like snout.1
Colour and pattern vary a great deal between subspecies and individuals.1
When threatened, it flattens its neck, hisses and may puff up its throat with air.1

常被誤認為： To an untrained eye, most individuals look much like rattlesnakes, which is thought to be a form of mimicry that makes predators wary. Its upturned snout and small, stout body are features to note.1

毒液力量

咬

咬的時候，毒液會從毒牙或牙齒出來。

牠的毒液有什麼作用？

The snake releases modified saliva from its Duvernoy's glands, which runs down a groove in its rear fang and helps break down the toxins of toads it eats. No deaths or whole-body (systemic) effects in people have been recorded from its bite. Bites may occasionally be medically significant.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。

The species is not dangerous to people and is not regarded as venomous. Its bites are extremely rare, and no deaths or systemic effects have been recorded. Bites may uncommonly be medically significant.1

牠害怕時會做什麼？

It flattens its neck, hisses and may make mock strikes with its mouth closed. If harassed further, it usually plays dead rather than biting.1

如果牠咬人

清洗咬傷處，讓傷者保持冷靜，並且就醫。有些種類（例如非洲樹蛇）可能在幾個小時後才致命。

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。
如果被牠咬了：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

牠有多大？

牠有多長？

跟 3 根香蕉頭尾相接一樣長跟 16 塊玩具積木排成一排一樣長可以在 77 秒內跑完 100 公尺（最快的人類需要 9.6 秒）

Western hognose snake 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？

一隻陸龜 大約 0,3 km/h (0,19 mph)

Western hognose snake 大約 4,7 km/h (2,9 mph)

一個正在走路的人 大約 5 km/h (3,1 mph)

值得知道

小知識

Captive breeders have produced more than 50 'designer' colour morphs of this snake.1

In captivity, many hognose snakes refuse food for about two to three and a half months, from January to mid March, because they instinctively brumate, or sleep, underground in winter.1

Males are considerably smaller than females.1

Hatchlings reach sexual maturity after about two years, based mostly on size rather than age.1

破解迷思

迷思： Because it looks like a rattlesnake, it must be dangerous or deadly.

真相： The western hognose snake is not dangerous to people. Its rare bites have not caused recorded deaths or whole-body effects, and it usually plays dead instead of biting.1

給毒液專家

學名: Heterodon nasicus
類群: 後毒牙蛇
家人: Colubridae2
排序: Squamata
各大洲: 北美洲
寶寶: It lays eggs. Females lay 4–23 elongate, thin-shelled eggs between June and August, which hatch after about 60 days.1
牠在野外的狀況: Least Concern (IUCN)1
對人的危險: 1 / 5: 輕微3