Rivulus Formosensis
📖 Overview
Rivulus Formosensis (Rivulus formosensis) is a ray-finned fish of the family Rivulidae. It inhabits freshwater waters. This species can reach a maximum total length of 3.3 cm. With a trophic level of 3.2, it is a low-level carnivore, feeding on invertebrates and small organisms.
🔬 Taxonomy
🐟 Physical Description
Dorsal soft rays (total): 10 - 11; Anal soft rays: 13 - 15; Vertebrae: 30. Diagnosed from all congeners by the presence of red marks on flank arranged in chevron-like pattern with a branching on the upper portion forming Y-shaped red marks in males. Additional characters not unique but useful to distinguish from all congeners when combined include: flank intense greenish blue, to purplish blue above anal-fin base in males; red marks on flank arranged in chevron-like pattern; sub-basal red stripe on the dorsal fin absent in males; absence of black reticulation on head in females; absence of orange pigmentation on caudal fin in females; 29-31 scales in the longitudinal series; frontal squamation E-patterned; 31-33 caudal-fin rays; pre-dorsal length 75.1-79.5% SL in males; and anal-fin base 20.6-23.0% SL in males; 18.2-20.0% SL in females .: elongated.
🌀 Behaviour
Behavioural data for Rivulus Formosensis is currently being reviewed.
🦐 Diet
🥚 Reproduction
🌍 Habitat & Distribution
Freshwater; benthopelagic; pH range: 5.6 - ?. Tropical South America: Formoso river floodplains, upper Corrente river drainage of the upper Paraná river basin in Brazil.
🌿 Ecology
📐 Morphometrics
🌡️ Water Parameters & Tolerance
📊 Population Risk & Fisheries
🔍 Similar Species
👥 Community & Contribute
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