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💧 Freshwater 🌡️ Tropical

Haplochromis Rex

Haplochromis rex Vranken, Van Steenberge, Heylen, Decru & Snoeks, 2022
Max Length
15.5 cm
Max Weight
-
Lifespan
-
Trophic Level
3.4
Depth
-
Climate
Tropical
Resilience
High
Vulnerability
23.00/100
Typical Length
-
Depth Zone
pelagic

📖 Overview

Haplochromis Rex (Haplochromis rex) is a ray-finned fish of the family Cichlidae. It inhabits freshwater waters in pelagic environments. This species can reach a maximum total length of 15.5 cm. With a trophic level of 3.4, it is a low-level carnivore, feeding on invertebrates and small organisms.

Scientific Name
Haplochromis rex
Authority
Vranken, Van Steenberge, Heylen, Decru & Snoeks, 2022
Habitat
Freshwater
Climate
Tropical
Max Length
15.5 cm
Trophic Level
3.4
Resilience
High
Vulnerability
23.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

Dorsal spines (total): 14 - 16; Dorsal soft rays (total): 9 - 11; Anal spines: 3; Anal soft rays: 8 - 10; Vertebrae: 29 - 31. Diagnosis: Species with a piscivorous morphology; head narrow, head width 36.8-41.6% of head length; cheek deep, cheek depth 27.6-33.5% of head length; eye small, eye diameter 22.2-28.3% of head length; outer oral teeth few and large, 24-36; dominant males cream-coloured with an orange operculum and a light blue snout . Amongst piscivorous species from the Lake Edward system, Haplochromis rex differs from H. latifrons and H. mentatus by the combination of a shorter caudal peduncle, caudal peduncle length 13.5-16.2% of standard length vs. 15.7-18.0%; and a narrower interorbital area, interorbital width 44.9-52.7% of head width vs. 51.3-63.3%; further from H. latifrons by absence vs. presence of a well-defined mid-lateral band; further from H. mentatus by dominant males cream-coloured with an orange operculum vs. yellow-green with a red anterior part of flank . It differs from H. simba by a combination of a larger number of longitudinal line scales, 34-38 vs. 32-33; a larger number of scales between first anal-fin spine and upper lateral line, 12-16 vs. 9-11; absent or weakly developed vs. strongly developed mental prominence; and dominant males cream-coloured with an orange operculum and a light blue snout vs. yellow with an orange anterior part of flank and a yellow snout . It differs from H. glaucus by the combination of a narrower interorbital area, interorbital width 44.9-52.7% of head width vs. 50.9-57.1%; a steeper snout, 40-50° vs. 30-40°; rounded vs. acute oral jaws in dorsal view; and dominant males cream-coloured with an orange operculum and a light blue snout vs. uniformly light blue with a dusky snout . It differs from H. aquila by the combination of a deeper lacrimal, lacrimal depth 18.9-22.5% of head length vs. 17.0-19.1%; smaller eye, eye diameter 22.2-28.3% of head length vs. 30.0-31.5%; and dominant males cream-coloured with an orange operculum vs. light grey with a black head .It differs from H. kimondo, H. falcatus, H. curvidens, H. pardus, H. quasimodo and H. squamipinnis by the combination of stout vs. slim oral jaws; large vs. small outer oral teeth; and a smaller number of outer upper jaw teeth, 24-36 vs. 39-79; it further differs from H. kimondo, H. curvidens and H. quasimodo by a narrower head, head width 36.8-41.6% of head length vs. 42.0-48.1%; further from H. kimondo and H. quasimodo by dominant males cream-coloured with an orange operculum vs. grey dorsally and yellow or blue-black ventrally; it further differs from H. falcatus, H. pardus and H. squamipinnis by a larger number of longitudinal line scales, 34-38 vs. 29-33, rarely 34; and dominant males cream-coloured with an orange operculum vs. uniformly olive-green with an orange-red anterior part of flank, speckled to uniformly black, or uniformly slate blue, respectively .

🌀 Behaviour

Behavioural data for Haplochromis Rex is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous 👄 Mouth Brooder 🛡️ Egg Guarder
Spawning Season
spring
Spawn Location
Substrate
Fertilization
External

🌍 Habitat & Distribution

Freshwater; pelagic. Tropical

🌿 Ecology

Zone Preferences
💧 Freshwater 🐟 Pelagic
Trophic Level
3.4±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.01445 × L2.99 (TL)
Max TL
15.5cm
Dorsal Spines
15
Dorsal Rays
10
Anal Spines
3
Anal Rays
9
Vertebrae
30

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

📊 Population Risk & Fisheries

Population Resilience
High
Minimum doubling time
Fishing Vulnerability
23.00/100
Low vulnerability
Trophic Level
3.4
Predator
Climate Zone
Tropical
Described By
Vranken, Van Steenberge, Heylen, Decru & Snoeks, 2022

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