📸 PhotoPhoto: Anilocra · Public domain · Wikimedia Commons Source
Herring worm
Anisakis simplex (Herring worm · アニサキス・シンプレックス)
Not Evaluated (NE) on the IUCN Red List yet.
💡 Everyday Comparisons for Size, Mass & Speed
- 💡 Its maximum larval length of 30 mm is slightly longer than the diameter of a Korean 500-won coin (26.5 mm) (Comparison).
- 💡 Marine fish and squid act as intermediate hosts, while whales, dolphins, and seals are the definitive hosts (ADW).
Reference standards: coach bus ~12 m, mid-size car ~4.9 m, compact car ~1 t, basketball hoop 3.05 m, credit card 8.56 cm.
📖 1. Overview
The herring worm is a marine parasitic nematode that matures in the stomachs of whales, dolphins, and seals. It reaches its definitive host via crustaceans, fish, and squid.
🦴 2. Anatomy & Morphology
Body length grows from 5 mm in 2nd-stage larvae to over 30 mm in 4th-stage larvae, with females being larger. Its body, covered in a collagen cuticle, molts four times during its life and has 3 lips around the mouth.
🔍 3. Ecology & Behavior
Eggs pass out in marine mammal feces and hatch, and free-swimming 2nd-stage larvae in seawater are eaten by crustaceans such as krill. Fish and squid that eat those crustaceans serve as intermediate hosts, and the worms finally mature when eaten by whales, dolphins, or seals. Adults feed on the host's stomach contents.
🇰🇷 4. Connection to Korea
It is listed as 'Goraehoechung' (Korean name) in the National List of Species of Korea.
📚 Sources & References
- • IUCN Red List: not evaluated (NE) — cross-checked with the Wikidata conservation-status entry
- • marinespecies.org — aphia.php
- • 국가생물종목록(국립생물자원관) ktsn 120000040749 — https://species.nibr.go.kr/home/mainHome.do?cont_link=009&subMenu=009002&contCd=009002&ktsn=120000040749
- • wikidata.org — Q2060647
- • commons.wikimedia.org — File:Anisakids.jpg
- • animaldiversity.org — Anisakis simplex
- • species.nibr.go.kr — mainHome.do
Recorded dimensions are widely cited representative estimates from public literature and may vary by study or specimen.