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💧 Freshwater Least Concern 🌡️ Tropical

Nomorhamphus Rex

Nomorhamphus rex Huylebrouck, Hadiaty & Herder, 2012
Max Length
4.4 cm
Max Weight
-
Lifespan
-
Trophic Level
3.1
Depth
-
Climate
Tropical
Resilience
-
Vulnerability
10.00/100
Typical Length
-
Depth Zone
pelagic

📖 Overview

Found in small, fast flowing river of few meters width that are partially covered by forest canopy, with gravel and sand bottoms. Occurs with Oryzias celebensis, Telmatherina cf. bonti, Anabas testudineus, Channa striata, Trichopodus pectoralis, Trichopodus pectoralis, Mugilogobius sp., Aplocheilus panchax, and Poecilia reticulata .

Scientific Name
Nomorhamphus rex
Authority
Huylebrouck, Hadiaty & Herder, 2012
Habitat
Freshwater
Climate
Tropical
Body Shape
Elongated
IUCN Status
LC
Max Length
4.4 cm
Trophic Level
3.1
Vulnerability
10.00/100
Salinity
0–0.5 ppt

🐟 Physical Description

Dorsal soft rays (total): 11 - 13; Anal soft rays: 14 - 15; Vertebrae: 37 - 40. This species is distinguished from its congeners by the shape of the andropodium in males: sickle-shape spiculus is curved dorsally, the proximal and middle segments in contact with the distal tip of the third anal-fin ray; the spiculus' distal segments are curved ventrally, no contact to third anal-fin ray; in males, the second anal-fin ray with 3 or 4 segments proximal to paired spines, third or fourth segment with a dorsal and a ventral row of 'subsegments' forming squares and rectangles of different sizes, the third or fourth segment appears to be subdivided into two separate rays, from the half of its length up to the spines, with a varying number of subsegments (?5 subsegments per row); first segment of the first anal-fin ray slightly constricted longitudinally, giving the appearance of 2 distinct rays; third anal-fin ray composed of 2 elongate segments, each approximately half the length of the entire ray, followed by a few short segments at the distal tip, which contact the spiculus; the fourth anal-fin ray divided into 3 rows from approximately the third of its length, forming a kind of a covering for the third anal fin ray with one dorsal and two lateral rows beneath . Nomorhamphus rex have a relatively longer lower jaw, LJLB 5.7-11.3 times in SL vs. 13.4-15.9 in N. ebrardtii and 8.8-22.2 in N. kolonodalensis .: elongated; Cross section: compressed.

🌀 Behaviour

Behavioural data for Nomorhamphus Rex is currently being reviewed.

🦐 Diet

Diet information for Nomorhamphus Rex is currently being compiled.

🥚 Reproduction

Reproduction data for Nomorhamphus Rex is currently being compiled.

🌍 Habitat & Distribution

Freshwater; pelagic; depth range 0 - ? m. Tropical

🌿 Ecology

Zone Preferences
💧 Freshwater 🐟 Pelagic
Trophic Level
3.1±0.4

📐 Morphometrics

Length–Weight Relationship: W = 0.00457 × L3.03 (TL)
Max TL
4.4cm
Dorsal Rays
12
Anal Rays
15
Vertebrae
39

🌡️ Water Parameters & Tolerance

Salinity Range
0–0.5ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2018

📊 Population Risk & Fisheries

Fishing Vulnerability
10.00/100
Low vulnerability
Trophic Level
3.1
Predator
Body Shape
Elongated
Climate Zone
Tropical
Described By
Huylebrouck, Hadiaty & Herder, 2012

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