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🌊 Marine Least Concern 🍽️ Edible 🌡️ Tropical

Longspine grunt

Rhencus macracanthus Günther, 1864
Max Length
37 cm
Max Weight
-
Lifespan
-
Trophic Level
3.5
Depth
1–30 m
Climate
Tropical
Resilience
Medium
Vulnerability
35.00/100
Typical Length
20 cm
Depth Zone
-

📖 Overview

Found near the littoral zone of coastal waters . Penetrates estuaries . Marketed fresh . Depth range assumed (RF).

Scientific Name
Rhencus macracanthus
Authority
Günther, 1864
Habitat
Marine
Climate
Tropical
Body Shape
Fusiform / normal
IUCN Status
LC
Max Length
37 cm
Depth Range
1–30 m
Latitude
2°S – 24°N
Trophic Level
3.5
Resilience
Medium
Vulnerability
35.00/100
Salinity
30–40 ppt

🔬 Taxonomy

Genus
Rhencus
Rhencus
Species
Longspine grunt
Rhencus macracanthus

🐟 Physical Description

Body oblong, moderately compressed, and somewhat deep (depth contained 2.5 to 2.7 times in standard length); mouth small and terminal, its posterior end located at the same level as the anterior rim of the eye; first gill arch with 18 to 23 gill rakers; dorsal fin deeply notched, with 12 to 14 spines and 13 to 14 soft rays (XII-IV, 13-14); dorsal and anal fins with a scaly sheath, the soft portions with international scales; second anal spine much stronger and longer than third; back dark brown or gray; belly silvery; back and flanks with 4 or 5 indistinct, dark, transverse bars (sometimes absent); operculum sometimes with a small, dark spot .: fusiform / normal.

🌀 Behaviour

Behavioural data for Longspine grunt is currently being reviewed.

🦐 Diet

aquatic invertebrates
small fish
algae
detritus

🥚 Reproduction

🐣 Oviparous

Oviparous, distinct pairing during breeding .

🌍 Habitat & Distribution

Marine; brackish; benthopelagic; depth range 1 - 30 m. Tropical; 24°N - 2°S, 110°W - 75°W

🌿 Ecology

Zone Preferences
🌊 Marine 🌿 Brackish
Trophic Level
3.5±0.5

📐 Morphometrics

Length–Weight Relationship: W = 0.01318 × L3.06 (TL)
Max TL
37cm

🌡️ Water Parameters & Tolerance

Salinity Range
30–40ppt

🛡️ Conservation Assessment

IUCN Category
Least Concern
Assessment Date
2007

📊 Population Risk & Fisheries

Population Resilience
Medium
Minimum doubling time
Fishing Vulnerability
35.00/100
Low vulnerability
Trophic Level
3.5
Predator
Body Shape
Fusiform / normal
Climate Zone
Tropical
Latitude Range
24°N – 2°S
Described By
Günther, 1864

🍽️ Edibility & Flavour

⚡ Nutrition

Per 100g cooked - Source: USDA FoodData Central

Nutrient Amount
Protein 18.2 g
Omega-3 (total) 225 mg

🔬 Mercury Safety

Mercury data for Longspine grunt has not yet been assigned. Please consult FDA/EPA guidance for general seafood safety advice.

🌿 Sustainability

Best Choice
Healthy stocks, low impact
Good Alternative
Well-managed, minor concerns
Use Caution
Check sourcing and season
Avoid
Overfished or high impact

📊 Population Dynamics

Year Region Index Notes
- - -

👥 Community & Contribute

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