Fishes · Bony fishes · Parrotfishes

Viridescent Parrotfish

Calotomus viridescens (Rüppell, 1835)
syn. Callyodon viridescens, Scarus viridescens
up to 27 cm1-30 mLeast Concern
882

It does not eat coral. This is the parrotfish that stayed in the meadow.

Where the rest of the family evolved a beak for biting rock and a mill for grinding it, this genus kept teeth that are only partly fused and feeds on seagrass, cropping the blades in sheltered bays and lagoons. That is a completely different living: the food is soft, it does not have to be crushed, and it grows in a habitat most parrotfish never enter.

It is also a reminder of where the family came from. Parrotfish are wrasses that specialized in scraping, and the seagrass-feeders sit closer to the starting point - less beak, less mill, less sand production, and none of the reef-shaping consequences the group is famous for.

So a meadow full of these is doing something quietly important. Seagrass grazing keeps blades short and productive, and the animals that do it here are few: turtles, dugongs, urchins, rabbitfish, and this small dotted parrotfish that almost nobody photographs because nobody dives seagrass on purpose.

Books print it as the dotted parrotfish, which is easier to use than the name on this card.

The genus. Calotomus Gilbert 1890 - calo- (beautiful) + tomos (cutting). ETYFish

The species. Calotomus viridescens (Rüppell 1835) - greenish. ETYFish

How to recognise it
  • small parrotfish in seagrass rather than on coral
  • mottled green-brown with scattered pale dots
  • teeth not fully fused into a beak, unlike the reef parrotfishes
  • up to 27 cm

Why it's threatened

There are no major threats known for this species.

Parrotfishes show varying degrees of habitat preference and utilization of coral reef habitats, with some species spending the majority of their life stages on coral reefs, while others primarily utilize seagrass beds, mangroves, algal beds, and /or rocky reefs. Although the majority of the parrotfishes occur in mixed habitat (primarily inhabiting seagrass beds, mangroves, and rocky reefs) approximately 78% of these mixed habitat species are experiencing greater than 30% loss of coral reef area and habitat quality across their distributions. Of those species that occur exclusively in coral reef habitat, more than 80% are experiencing a greater than 30% of coral reef loss and degradation across their distributions. However, more research is needed to understand the long-term effects of habitat loss and degradation on these species populations. Widespread coral reef loss and declining habitat conditions are particularly worrying for species that depend on live coral reefs for food and shelter especially as studies have shown that protection of pristine habitats facilitate the persistence of adult populations in species that have spatially separated adult and juvenile habitats. Furthermore, coral reef loss and declining habitat conditions are particularly worrying for some corallivorous excavating parrotfishes that play major roles in reef dynamics and sedimentation (Comeros-Raynal et al. 2012).

Threat classification from the IUCN Red List.

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Last Update: August 20, 2026