The main threat to its survival is the large-scale destruction of the old-growth rainforest that it requires, and in 2018 it was estimated that the species was restricted to a total area of just 31 km2 (12 sq mi).

Its diet consists of invertebrates such as ants and caterpillars, preferably picked from the horizontal, lichen-covered branches of large trees; the birds have also been observed feeding on fruit.

The cherry-throated tanager was described in 1870 by the German ornithologist Jean Cabanis of the Natural History Museum, Berlin, as Nemosia rourei.

Cabanis based the description on a single specimen sent to him by the Swiss ornithologist Carl Euler, who lived on a fazenda in the state of Rio de Janeiro.

[5] There is, however, evidence that two additional specimens existed: In 1926, the ornithologist Emilie Snethlage, while reporting on her failed attempts to find an individual of the species in the wild, mentioned a mounted pair in the collection of the National Museum of Brazil in Rio de Janeiro.

[8] The cherry-throated tanager is a visually distinctive bird with an overall gray, black, and white plumage and a conspicuous bright red patch on the chest and throat.

In the latter case, it is typically followed by two shorter and high-pitched notes that have been described as "see'ee" or "pit-pit", and additional "péuuu" calls may be added to the middle or end of the sequence.

[4][5][10] Another vocalization consists of the same notes but is less regular and interspersed with rapid chittering; it is given especially when the birds reply to tape recordings and therefore might represent the song.

[5] The cherry-throated tanager is a local endemic of the Atlantic Forest, the second largest rainforest of the Americas, and one of the most biodiverse regions in the world.

[5] The cherry-throated tanager currently occurs at only two localities – the Augusto Ruschi Biological Reserve and the Caetés forest – and had been recorded from at least two others (Itarana and Conceição do Castelo) from which it has disappeared.

Those in which N. rourei was observed to participate were usually led by sibilant sirystes and contained chestnut-crowned becards and rufous-headed tanagers as "core" species.

[5] Feeding takes place in the forest canopy on tall trees, preferably on large and horizontal branches with abundant lichen.

Here, the birds search for prey with quick hops, extending their necks to pick up food items from the side and undersides of branches, from leaves, and beneath lichen.

In the following two years, three groups of ornithologists visited the fazenda for multiple days in an attempt to confirm Brettas's observation, but did not encounter the species.

In 2000, Claudia Bauer and colleagues pointed out that the extent of the black face mask as seen in the 1993 book illustration is incorrect, and that Brettas's sketch showed the same mistake, adding to the doubts about the observation's validity.

In a 1997 publication discussing his observation, Scott noted that the bird he saw clearly matched the cherry-throated tanager, but that the red throat patch was not pointed and extending over the breast as in the holotype specimen, but square-shaped.

[4] The species was rediscovered by a group of six ornithologists on February 22, 1998, in a forest fragment that is part of the Fazenda Pindobas IV, in Conceição do Castelo.

Two days later, the researchers returned to the site to document their observation; they encountered the same flock, this time containing four cherry-throated tanagers and 18 other bird species.

[4][19] The rediscovery of the species prompted a number of surveys in search for additional populations, and the newly gained knowledge about the bird's distinctive calls facilitated observations.

In 2002, the British ornithologist Guy M. Kirwan heard the calls in the Augusto Ruschi Biological Reserve, where Scott had made his possible observation in 1995.

[13]: 6 As of 2024,[update] the cherry-throated tanager is thought to survive at only two localities – the Augusto Ruschi Biological Reserve and the Caetés forest – and has probably disappeared from at least two areas where it was previously recorded.

[5] At the Fazenda Pindobas IV in Conceição do Castelo, where Bauer rediscovered the species in 1998, the birds were regularly observed in subsequent years in two connected forest fragments.

In 2002, a company explored another property bordering one of the forest fragments for marble and granite using explosives; the detonations led to a decrease in activity of the cherry-throated tanagers and of other bird species.

Remaining forest fragments are often insufficiently protected and become the target of real estate speculation, are cleared to gain space for crops such as coffee and Eucalyptus, and are affected by the construction of new infrastructure and urbanization.

[5][13]: 21–23 Additional threats include the mining of granite, marble, and limestone that produces dust and leads to heavy traffic and noise pollution due to frequent blasting.

The effects of climate change on the region remain poorly understood but will probably include higher temperatures, less rain, and more frequent storms.

[22] In 2021, the Marcos Daniel Institute, supported by several nonprofits, acquired another 6.67 km2 (2.58 sq mi) to create a second private reserve, the Reserva Kaetés.

[23] The entire Caetés forest was included in the Pedra Azul–Forno Grande ecological corridor, a priority area for conservation recognized by the state.

To increase breeding success, potential predators such as black capuchins and channel-billed toucans were chased away, and supplemental feeding of mealworms has been tried.

[13]: 44 [21][24] Such public engagement may directly benefit lesser-known Atlantic Forest endemics; for example, farmers have discovered additional localities of the critically endangered catfish Trichogenes claviger after learning about this species during campaigns focused on the cherry-throated tanager.