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💧 Freshwater Least Concern 🌡️ Tropical

Marjorie's hardyhead

Craterocephalus marjoriae Whitley, 1948
Max Length
8.5 cm
Max Weight
-
Lifespan
-
Trophic Level
2.9
Depth
-
Climate
Tropical
Resilience
High
Vulnerability
27.00/100
Typical Length
5 cm
Depth Zone
-

📖 Overview

Lives in clear flowing streams where it is common along the vegetated margin. Generally in shallow water over sandy or gravelly substrates. A shoal-forming species. Capable of multiple spawnings between September and January (with peak activity early in the season). It has reproduced in captivity . Feeds mostly on aquatic insects and their larvae, micro-crustaceans, algae and fish eggs .

Scientific Name
Craterocephalus marjoriae
Authority
Whitley, 1948
Habitat
Freshwater
Climate
Tropical
Body Shape
Elongated
IUCN Status
LC
Max Length
8.5 cm
Trophic Level
2.9
Resilience
High
Vulnerability
27.00/100
Water Temp
24–30 °C
Salinity
0–0.5 ppt

🔬 Taxonomy

🐟 Physical Description

Distinguished from Craterocephalus marianae and Craterocephalus munroi and all other members of the genus by a combination of the following: head 3.0-3.4 (3.1); greatest body depth 3.6-4.7 (4.1); least body depth 8.8-11.0 00.0); origin of pectoral fin to anus 2.7-3.1 (2.9), all in SL. Dorsal process of premaxilla 1.1-1.70.4 in eye. Midlateral scale count 28-30 (29.1); transverse scale count 5.5-6.5 (6.0); vertebral count 30-32 (31.4). Position of anus in relation to tip of pelvic fin from 0.5 scales in front to 2 scales behind tip of pelvic fin. Differs osteologically from all other Craterocephalus species by a combination of the following: shape of anterior medial process of maxilla; lack of interdorsal pterygiophores (but shared with some other members of C. eyresii group); minute anterior process usually present on cleithrum; dorsal process of cleithrum also present; basisphenoid short and thick. Differs genetically from Craterocephalus marianae at the following loci: ADA, CK, FDP, GPI-l,MPI, PGM and from C. munroi at CK, FDP, GLDH, GPI-l, MPI, PGM. Unique at GPI-lf .: elongated.

🌀 Behaviour

Behavioural data for Marjorie's hardyhead is currently being reviewed.

🦐 Diet

Diet information for Marjorie's hardyhead is currently being compiled.

🥚 Reproduction

Reproduction data for Marjorie's hardyhead is currently being compiled.

🌍 Habitat & Distribution

Freshwater; benthopelagic. Tropical; 24°C - 30°C endemic to Australia.

🌿 Ecology

Zone Preferences
💧 Freshwater
Trophic Level
2.9±0.36

📐 Morphometrics

Length–Weight Relationship: W = 0.00389 × L3.12 (TL)
Max TL
8.5cm

🌡️ Water Parameters & Tolerance

Temperature Range
24–30°C
Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
27.00/100
Low vulnerability
Trophic Level
2.9
Omnivore / Planktivore
Body Shape
Elongated
Climate Zone
Tropical
Described By
Whitley, 1948

🗺️ Global Occurrence Map

Occurrence records from the Global Biodiversity Information Facility (GBIF) - 2 records indexed .

Occurrence density from GBIF View GBIF records ↗

👥 Community & Contribute

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