📸 PhotoPhoto: NOAA · Public domain · Wikimedia Commons Source
Smooth hammerhead
Sphyrna zygaena (Smooth hammerhead · シロシュモクザメ)
💡 Everyday Comparisons for Size, Mass & Speed
- 💡 The mother's size of about 4 m cited in the National List of Species of Korea is nearly equal to the length of a passenger car (about 4.5 m) (Comparison).
- 💡 A newborn pup's total length of 50–60 cm is about the length of a folding umbrella (Comparison).
- 💡 It is recorded along all coasts of Korea and is targeted by commercial fisheries and anglers (National List of Species of Korea, FishBase).
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.
Site-computed relative index from recorded values; not a formal scientific metric.
📖 1. Overview
The smooth hammerhead is a shark whose head extends wide to the left and right like a hammer, recorded along all coasts of Korea. It is fierce and swims actively in search of prey.
🦴 2. Anatomy & Morphology
Its body is streamlined with a round cross-section, and its eyes sit at the tips of its hammer-shaped head. The width of the head is about 2 times its length, and the 5 undulations along the front edge of the head become more distinct as it grows.
🔍 3. Ecology & Behavior
It feeds on small sharks, rays, bony fish, shrimp, crabs, and squid. It is viviparous, usually giving birth to 30–36 pups per litter, each measuring 50–60 cm in total length at birth. Young sharks sometimes form large schools of hundreds of individuals.
🇰🇷 4. Connection to Korea
It is listed on the National List of Species of Korea as occurring along all coasts of Korea.
📚 Sources & References
- • IUCN Red List VU (2019) — https://www.iucnredlist.org/species/39388/2921825
- • IUCN Red List category VU — latest assessment at iucnredlist.org
- • catalogueoflife.org — 4Z2QW
- • iucnredlist.org — 2921825
- • 국가생물종목록(국립생물자원관) ktsn 120000057311 — https://species.nibr.go.kr/home/mainHome.do?cont_link=009&subMenu=009002&contCd=009002&ktsn=120000057311
- • wikidata.org — Q726259
- • commons.wikimedia.org — File:Sphyrna zygaena noaa.jpg
- • fishbase.se — Sphyrna-zygaena.html
- • species.nibr.go.kr — mainHome.do
- • Silhouette: PhyloPic — author not recorded · CC0 1.0 (Congeneric silhouette — Sphyrna)
Recorded dimensions are widely cited representative estimates from public literature and may vary by study or specimen.