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Diadromous Least Concern 🌡️ Temperate

Shorthead lamprey

Mordacia mordax Richardson, 1846
Max Length
50 cm
Max Weight
-
Lifespan
-
Trophic Level
4.3
Depth
-
Climate
Temperate
Resilience
Low
Vulnerability
41.00/100
Typical Length
37.5 cm
Depth Zone
demersal

📖 Overview

Adults inhabit the sea for an undetermined period and are parasitic on fishes; enter freshwater to breed. Majority of adulthood is spent in estuaries or at sea. Upstream spawning migrants occur in fast-flowing sections of rivers with a mud, sand or silt substrate, sometimes seen congregated below barriers to upstream movement such as weirs. Ammocoetes live in slow-flowing streams, burrowed in mud or silt. Common length is 35-40 cm . Larval life is 3.5 yrs. During the spawning migration, adults burrow in the substrate of rivers during the day and migrate upstream during the night. Fecundity, 3,789-13,372 eggs/female. De Castelnau (1872) states that the adults from the lower Yarra River, Victoria, are considered good food .

Scientific Name
Mordacia mordax
Authority
Richardson, 1846
Habitat
Diadromous
Climate
Temperate
IUCN Status
LC
Max Length
50 cm
Trophic Level
4.3
Resilience
Low
Vulnerability
41.00/100
Migration
Anadromous
Salinity
30–40 ppt

🐟 Physical Description

Adults: 11.3-43.2 cm TL; body proportions of pre-spawning specimens, as percentage of TL (based on 125 prespawning specimens measuring 11.3-42.1 cm TL): 8.5-11.3 prebranchial length, 7.1-9.8 branchial length, 60.4-68.3 trunk length, 14.4-20.1 tail length, 1.1-1.7 eye length and 4.9-6.6 disc length. Body proportions of spawning male specimens, as percentage of TL (based on 8 spawning males measuring 27.7-37.6 cm TL): 11.4-16.6 prebranchial length, 8.8-10.1 branchial length, 60.1-65.3 trunk length, 13.3-15.7 tail length, 8.1-11.2 disc length. Mature males with some loose skin in gular region. Urogenital papilla not prominent in mature adults; trunk myomeres, 84-96. Adult dentition: 2 triangular supraoral laminae each with 3 unicuspid teeth, 1 per apex; infraoral lamina, 7-9 unicuspid teeth of various size (these teeth become greatly enlarged with sexual maturation); 5-7 endolateral plates on either side each bearing 2-3 unicuspid teeth, usually 3; endolateral formula, typically 2-3-3-3-3-3 in immature individuals and 5-7 individual cusps on either side in mature individuals; 1 row of anterials; first row of anterials, 2 unicuspid teeth plus 1-2 bicuspid teeth or 3 unicuspid teeth flanked on either side by 1 bicuspid tooth; 1 row of exolaterals on each side; 1 row of posterials; first row of posterials, 12-14 posterial plates, the 2-4 lateralmost tricuspid and the internal ones bicuspid in immature individuals and 12-14 unicuspid teeth in mature individuals; transverse lingual lamina w-shaped, with 29 unicuspid teeth, the median one and the 2 subterminal ones slightly enlarged; longitudinal lingual laminae interrupted j-shaped, each with an undetermined number of unicuspid teeth. Velar tentacles in adults, 3-4, smooth. Body coloration (live) of immature adults brownish gray on dorsal surface and silvery on ventral surface; lateral line neuromasts darkly pigmented; caudal fin pigmentation, 25% to

🌀 Behaviour

Behavioural data for Shorthead lamprey is currently being reviewed.

🦐 Diet

small fish
crustaceans
cephalopods

🥚 Reproduction

🐣 Oviparous 📦 Batch Spawner
Spawning Season
spring
Spawn Location
Substrate
Fertilization
External

Semelparous .

🌍 Habitat & Distribution

Marine; freshwater; brackish; demersal; anadromous . Temperate; 35°S - 44°S South Wales to Gulf of St.

🌿 Ecology

Zone Preferences
🌊 Marine 💧 Freshwater 🌿 Brackish ⬇️ Benthic
Migration
Anadromous
Trophic Level
4.3±0.8

📐 Morphometrics

Length–Weight Relationship: W = 0.00102 × L3.06 (TL)
Max TL
50cm

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
Low
Minimum doubling time
Fishing Vulnerability
41.00/100
Moderate vulnerability
Trophic Level
4.3
Apex / Top predator
Climate Zone
Temperate
Described By
Richardson, 1846

🌐 Names & Taxonomy

Language Common Names
🇬🇧English Australian lamprey · Murray Lamprey · short-headed lamprey
🇸🇦Arabic جلكى أسترالية
🌍CES mihule tasmánská
🇫🇮Finnish australiannahkiainen
🇫🇷French lamproie australienne
🇵🇹Portuguese Lampreia-de-Murray
🇷🇺Russian Короткоголовая австралийская минога

Scientific Synonyms

Scientific Name Author Year Status
Petromyzon mordax Richardson 1846 Synonym

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 3 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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