第 0722 號，共 1 402 號

Hobo spider

Eratigena agrestis

名字的由來： The genus name Eratigena is an anagram of Tegenaria, the genus it was moved out of in 2013.1

無害對人無害。不用擔心。

蜘蛛

咬吃：昆蟲

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 hobo spider is a brown spider that lives in fields, woods and under rocks in Europe, Central Asia and western North America. It builds a funnel-shaped sheet of silk and waits at the narrow end for insects to crawl on. It sometimes builds webs in or around homes, so people often worry about its bite.1

分布在

Europe to Central Asia, and western North America (Pacific Northwest and Great Basin)1

歐洲, 亞洲

首頁

Hobo spiders live mostly in fields, woods and under rocks. They sometimes build webs in or around human homes. They often make a horizontal, trampoline-like web near brick walls or wood piles, where they have shelter and wait for prey.1

長度

1,4 cm (0,6 in)1

最高速度

大約 1 km/h（0,62 mph）

在陸地上, 粗略估計

牠吃什麼？

Hobo spiders catch prey insects that blunder onto their funnel webs. They wait at the small end of the funnel for the insects to arrive.1

Hobo spider 的照片 — Hobo spider。照片：Tone Killick。 CC BY 4.0, iNaturalist.

怎麼認出牠

Body length is 7 to 14 mm, and the spider is brownish in colour.1
The abdomen has V-shaped chevron patterns down the middle, pointing towards the head.1
There is a light stripe running down the middle of the underside (sternum).1
There are no coloured bands where the leg joints meet.1
The top of the front body section (cephalothorax) has indistinct or diffused patterns, not two distinct dark stripes.1

常被誤認為： Other Eratigena species have three or four pairs of light spots on the sides of the sternum rather than a central stripe, though these spots can be very faint. Spiders in the genera Agelenopsis and Hololena, and possibly some wolf spiders, have two distinct dark stripes on the top of the front body section. Positive identification of hobo spiders usually requires microscopic examination of their sex organs by an expert.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？

There is no clear evidence that the hobo spider has venom that is dangerous to humans. Earlier case reports linked its bites to isolated cases of necrosis, which is the death of skin tissue, but this is no longer supported.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。

There is little evidence that the hobo spider is dangerously venomous. The US CDC no longer lists it among venomous species, as of 2017. In Canada there is no evidence that its bites cause skin necrosis.1

如果牠咬人

清洗咬傷處，用冰敷袋冰敷止痛。如果很痛、疼痛擴散或傷者覺得不舒服，要就醫。

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？

小到可以坐在你的指甲上可以在 360 秒內跑完 100 公尺（最快的人類需要 9.6 秒）

Hobo spider 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)

Hobo spider 大約 1 km/h (0,62 mph)

一個正在走路的人 大約 5 km/h (3,1 mph)

值得知道

小知識

In Europe, hobo spiders mostly avoid houses because the larger giant house spider lives there and competes with them, so human contact is uncommon.1

The male hobo spider dies after mating.1

A hobo spider was probably carried to the small artificial Danish island of Peberholm by trains.1

破解迷思

迷思： Hobo spiders have dangerous venom that causes skin necrosis.

真相： There is little clear evidence that the hobo spider's venom is dangerous to humans. Some bites reported as hobo spider bites may have been from the desert grass spider.1