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💧 Freshwater Least Concern 🌡️ Tropical

Tandanus Tropicanus

Tandanus tropicanus Welsh, Jerry & Burrows, 2014
Max Length
39.5 cm
Max Weight
-
Lifespan
-
Trophic Level
3.5
Depth
-
Climate
Tropical
Resilience
Medium
Vulnerability
39.00/100
Typical Length
-
Depth Zone
demersal

📖 Overview

Tandanus Tropicanus (Tandanus tropicanus) is a ray-finned fish of the family Plotosidae. It inhabits freshwater waters in benthic environments. This species can reach a maximum total length of 39.5 cm. With a trophic level of 3.5, it is a low-level carnivore, feeding on invertebrates and small organisms. It is assessed as Least Concern on the IUCN Red List.

Scientific Name
Tandanus tropicanus
Authority
Welsh, Jerry & Burrows, 2014
Habitat
Freshwater
Climate
Tropical
IUCN Status
LC
Max Length
39.5 cm
Trophic Level
3.5
Resilience
Medium
Vulnerability
39.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

Dorsal soft rays (total): 5 - 6; Anal soft rays: 150 - 165. Tandanus tropicanus is distinguished from its congener T. tandanus from different drainages. In the Murray-Darling drainage, it differs from T. tandanus by having the following characters: 150-165, mode 156 rays in the continuous caudodorsal and anal fins (vs. 136-149, mode 143); 31-35, mode 31, gill rakers on the first arch (vs. 24-30, mode 28); interorbital width 32.9-38.4% of HL mean 36.2% (vs. 40.3-47.7%, mean 43.5%); pectoral spine 11.1-14.0% of SL, mean 12.4% (vs. 8.9-11.2%, mean 10.1%). For individuals >20.5 cm SL, T. tropicanus can be diagnosed from T. tandanus of the Murray-Darling drainage by having 12-19 (mode 14) posterior serrae on the pectoral-fin spine (vs. 7-11, mode 9). Also, individuals >7.0 cm HL, T. tropicanus differs from T. tandanus of the Murray-Darling drainage by having the following characters: length of the inner mandibular barbel 32.3-41.0% of HL, mean 36.1% (vs. 40.9-54.7%, mean 46.7%); distance between bases of outer mandibular barbels 27.4-33.8% of HL, mean 29.6% (vs. 21.2-25.9%, mean 24.4%); distance between bases of inner mandibular barbels 13.5-15.9% of HL, mean 14.8% (vs. 10.4-13.2%, mean 12.0%); distance between bases of maxillary barbels 47.0-53.5% of HL, mean 50.1% (vs. 39.5-46.6%, mean 44.2% ); maximum cleithral width 75.6-81.4% of HL, mean 78.2% (vs. 68.6-75.2%, mean 71.9%); and eye diameter 14.7-17.2% of HL, mean 15.6% (vs. 12.3-14.6%, mean 13.6%). In the eastern coastal drainages of Australia (Burnett, Tweed, Brisbane, Fitzroy, Clarence, Mary, and Richmond), Tandanus tropicanus differs from T. tandanus by having the following features: 150-165 rays (mode 156) in the continuous caudodorsal and anal fins (vs. 132-147, mode 145); gill rakers on the first arch 31-35, mode 31 (vs. 27-30, mode 28); interorbital width 32.9-38.4% of HL, mean 36.2% (vs. 40.2-47.3%, mean 43.2%); and to a lesser degree, a longer pectoral spine (11.1-14.0% of SL, mean 12.4% vs. 10.0-11.1%, mean 10.5%, respectively). For individuals >20.5 cm SL, T. tropicanus differs from T. tandanus by having more posterior serrae on the pectoral-fin spine (range 12-19, mode 14 vs. 7-11, mode 10). Tandanus tropicanus can be differentiated from Bellinger catfish by having a larger eye diameter (14.7-18.5% of HL, mean 16.3% vs. 13.2-14.4%, mean 13.8%, respectively), a longer pectoral spine (11.1-14.0% of SL, mean 12.4% vs. 9.8-10.7%, mean 10.4%, respectively) and, to a lesser degree, fewer gill rakers on the first arch (range 31-35, mode 31 vs. 35-39, respectively). It is distinct from T. bostocki by a shorter post-orbital distance (37.4-42.7% of HL, mean 39.5% vs. 46.7-55.9%, mean 51.9%, respectively), a longer snout (44.1-52.3% of HL, mean 48.9% vs. 37.6-42.1%, mean 39.8%, respectively), and, to a lesser degree, a larger eye diameter (14.7-18.5% of HL, mean 16.3% vs. 11.9-15.5%, mean 13.3%, respectively), more rays in the continuous caudodorsal and anal fins (range 150-165, mode 156 vs. 139-149, mode 147, respectively), more gill rakers on the first arch (range 31-35, mode 31 vs. 18-22, mode 21, respectively), and prominent (vs. reduced) posterior serrae on the pectoral-fin spine, respectively .

🌀 Behaviour

Behavioural data for Tandanus Tropicanus is currently being reviewed.

🦐 Diet

Diet information for Tandanus Tropicanus is currently being compiled.

🥚 Reproduction

Reproduction data for Tandanus Tropicanus is currently being compiled.

🌍 Habitat & Distribution

Freshwater; demersal. Tropical northeast Queensland, including the Daintree, Mulgrave-Russell, Johnstone, Tully, and Five Mile drainage basins.

🌿 Ecology

Zone Preferences
💧 Freshwater ⬇️ Benthic
Trophic Level
3.5±0.6

📐 Morphometrics

Length–Weight Relationship: W = 0.00724 × L3.08 (TL)
Max TL
39.5cm
Dorsal Rays
6
Anal Rays
158

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2019

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
39.00/100
Moderate vulnerability
Trophic Level
3.5
Predator
Climate Zone
Tropical
Described By
Welsh, Jerry & Burrows, 2014

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