This species has been frequently misidentified as S. taeniopterus and S. iseri. Its status as a distinct species was recognized by Moura et al. (2001) on the basis of scale counts and color pattern.

Westneat and Alfaro (2005) recognize the Scarini as a tribe within the family Labridae. The genera Chlororus and Scarus are two distinct monophyletic lineages (Smith et al. 2008).

This species is endemic to Brazil where it is considered common across its range. It is fished in many areas particularly by spearfishing, especially in the southern limits of its range. However, there is not enough data to estimate global population trends and apparently there may not be a decline in the central and northern part of its range. It is listed as Data Deficient. This species should be re-evaluated when more data on population trends and fisheries are available.

This species is endemic to Brazil and occurs from Manoel Luis Reefs in northeastern Brazil to the São Paulo coast in southeastern Brazil. It is absent from all Brazilian oceanic islands.

This species is less common than other scarids in Brazil.

In the Abrolhos Bank, a region with Brazil’s largest network of marine protected areas, S. zelindae represents 0.9% of total reef fish biomass (Francini-Filho and Moura 2008), with highest values recorded within the no-take zone of Timbebas Reef (Francini-Filho 2005). Considering the entire Abrolhos Bank (i.e. both protected and unprotected reefs), there is no clear pattern of decreased abundance between 2001 and 2004 (Francini-Filho 2005). However, in one area open to fishing densities declined by 50% between 2001 and 2004 (Francini-Filho 2005).

This species occurs in coralline areas and rocky reefs at depths of 1 to 60 m. Scarus zelindae is predominantly herbivorous, ingesting algae and detritus (Ferreira and Gonçalves 2006). When compared to its other Brazilian congeners, it prefers crustose coralline algae. This species life history is not known. Based on a sister species in Bermuda, S. taeniopterus, longevity is estimated to be 12 years and average age of maturity would be 2 to 3 years. Therefore, the generation length is estimated to be 7.5 to 8 years.

This species is fished in many areas of its range, especially by spearfishing in the southern portion of its range. Although data is limited, there does not appear to be any decline in the central and northern part of its range. However, in one area open to fishing near Abrolhos Bank, densities declined by 50% between 2001 and 2004 (Francini-Filho 2005). There is not enough data to estimate global population trends or decline.

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).

This species is targeted by spearfishers. It is rare in the aquarium trade. In 2007, there were 45 individuals exported for the aquarium trade (BOSOT 2007).

There is no register of the catch of this species by traps and line, but it is regularly targeted by spearfishers, a fishing technique with increasing numbers of practitioners in the last decades, both recreational and professional. In addition, entire multi-specific groups of scarids, including S. zelindae, are sometimes captured with drive nets above the reefs, particularly in the Abrolhos Bank. Compared to other parrotfishes, this species is less frequently seen in trap fisheries at least in the northern portion of its range. However, there is concern for this species in the southern portion of its range where is targeted in spearfishing. More information is needed on this species population trends, life history, and the impact of fisheries on its population especially in the southern portion of its range.

This species is present in marine protected areas along the Brazilian coast, such as Recifes de Corais MPA, Costa dos Corais MPA, Abrolhos National Park. There is a collection quota of 1000 individuals/company/year for the aquarium trade. The effective implementation of the few marine protected areas in Brazil represent the most urgent conservation action to protect S. zelindae and the other large-sized Brazilian-endemic parrotfishes. The creation of new protected areas also ranks within priority actions for reef fish conservation in Brazil. Brazilian reefs, highly threatened by the country’s explosive growth, represent a priority area for biodiversity conservation in the Atlantic, due to their small relative area (0.5% of the world’s reefs) and concentration of high levels of endemism (up to 30% in reef fishes). Of particular concern is the disproportionately low redundancy for large-bodied parrotfish.

Remarkable sites where it is recorded include:
1) Manoel Luis Reefs (Parcel Manoel Luís), a large reef complex near the Amazon River mouth (Moura et al. 1999)
encompassed by a State Marine Park created in 1991 and recognized as a RAMSAR Site. Although legally protected, Manoel Luis represent a paper park with no protection and research incentives or infrastructure, being systematically exposed to illegal fisheries by fleets based in or near the city of São Luis, Maranhão State.

2) João da Cunha Reef (Recifes João da Cunha), located in the border between Ceará and Rio Grande do Norte States, these reefs represent the second larger coralline formations in the Northern coast of Brazil (with and E-W orientation) under influence of the west-flowing Equatorial current (the largest reef is Manoel Luis). Density estimates for S. zelindae are available for a few sites and habitats within these reefs (Moura 2003), which were severely damaged by a seaport construction in the 1970s and chronic overfishing.

5) Maracajaú, a large complex of non-emerging coastal reefs off the Rio Grande do Norte State coast, included in the Área de Proteção Ambiental dos Recifes de Corais (established in 200X). Although legally established, this multiple-use protected area provides limited protection as it is not yet implemented and lacks no-take reserves. Scarus zelindae was recorded in Maracajaú by Ferreira and Maida (2006), but there are no specific data on its density in the area.

6) Paraíba State, an important reef area in the northeastern Brazilian coast where S. zelindae was recorded by Rocha et al. (1998). It is remarkable that coastal reefs in Paraíba State are already critically damaged by water quality decline, overfishing and mass tourism, and still lack no-take marine protected areas. Best preserved reefs are those in the mid and outer shelf (Feitozaet al. 2005), where S. zelindae occurs in depths up to 54 m, but these are also nearly depleted of large sized commercially important reef fish species.

7) Pernambuco and Alagoas States (Corals Coast), a huge coastal area with coastal and mid/outer shelf reefs, encompassed by the largest Brazilian marine protected area (established in 1997), representing an important area where S. zelindae occurs. Although bearing a few small no-take zones, this MPA still lacks zoning, management plan and enforcement in order to effectively protect S. zelindae and other commercially-exploited parrotfish populations.

8) Abrolhos Bank, a wide portion of the continental shelf (42 000 km^2) with depths rarely exceeding 30 m, the Bank
encompasses the largest and richest coralline reefs in Brazil, where all 18 coral species recorded in Brazil co-occur. Within the Abrolhos Bank S. zelindae is common in both shallow coastal reefs and deeper offshore areas (Moura and Francini-Filho, 2006). There are three main marine protected areas (MPAs) in the region, the “Área de Proteção Ambiental Ponta da Baleia-Abrolhos” (340,000 ha, created in 1993), a “paper park” with no implementation since its legal establishment by the State of Bahia government, the Corumbau Extractive Reserve (89,500 ha, created in 2000), with management plan and zoning, but currently with deficient enforcement (Moura et al. 2007), and the Abrolhos National Marine Park (88,200 ha, created in 1983), the first Brazilian National Marine Park, counting with management plan and zoning, but currently with a heavily deficient enforcement. Despite this MPA network, effectively protection of S. zelindae and other commercially exploited parrotfish populations is not being provided.

10) Southeastern Brazil coastal islands. Significant groups of islands occur off the coast of Espirito Santo, Rio de Janeiro, São Paulo and Santa Catarina states. Scarus zelindae occurs in low densities throughout the region (e.g. Floeter et al. 2007, Luiz Jr. et al. 2008), being more common in islands than in the mainland coastlines, with numbers decreasing from the North to South. There are few MPAS in the southeastern region, and most existing ones are not implemented and lack management plans and enforcement.