Red-fin Thresher Plecostomus L116 Care Guide

Aphanotorulus emarginatus · Freshwater Fish

Red-fin Thresher Plecostomus L116
AI-generated illustration of Red-fin Thresher Plecostomus L116
Temperature
72-82°F
pH
6.0-7.5
Adult size
~12″ (30.5 cm)
Suggested tank
20+ gal

What Red-fin Thresher Plecostomus L116 look like

Aphanotorulus emarginatus, commonly known as the Red-fin Thresher Plecostomus L116, exhibits a robust, laterally compressed body that can reach a maximum adult size of approximately 10 to 14 inches. The species is characterized by a dark, almost blackish-brown body adorned with striking red to orange margins on its pectoral and dorsal fins, which serve as a key identifying feature. The fish possesses a heavily armored integument, with bony plates providing significant protection against predation. Its mouth is adapted for a sucker-like feeding mechanism, equipped with specialized dentition that allows it to graze on algae and detritus. Notably, this species lacks pronounced sexual dimorphism; however, males may exhibit slightly more vibrant fin coloration during breeding periods. The presence of a well-defined lateral line aids in the detection of vibrations in the water, enhancing its ability to navigate its environment and locate food sources.

Behavior & temperament

The Red-fin Thresher Plecostomus L116 is primarily a benthic species, often found dwelling near the substrate of rivers and lakes, where it prefers to inhabit areas with ample hiding spots among rocks and vegetation. It exhibits a semi-social behavior, often forming loose aggregations, but can also be found solitary, particularly in larger territories. This species is generally peaceful but may display territorial aggression towards conspecifics, especially males during breeding seasons. Breeding behavior involves egg scattering, with females laying adhesive eggs on flat surfaces, which are then fertilized by males. The species is known for its relatively calm temperament, making it suitable for community tanks, provided that tank mates are not overly aggressive.

Diet & feeding

In the wild, Aphanotorulus emarginatus is an omnivorous feeder, primarily consuming algae, detritus, and small invertebrates. In captivity, it thrives on a varied diet that includes high-quality sinking pellets, fresh vegetables, and occasional protein sources such as bloodworms or brine shrimp.

Behind the name

Aphanotorulus (from Greek 'aphano' meaning 'invisible' and 'torulus' meaning 'little wheel'); emarginatus (from Latin 'emarginare' meaning 'to notch' or 'to cut out').

Plan your tank

Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.

Keeping Red-fin Thresher Plecostomus L116?

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