A recently discovered songbird from the Babar Islands in Indonesia’s Banda Sea has been recognized as a new species. This small bird, named the Merry Fantail (Lipidula laguceria), stands out due to its unique song, which differentiates it from its close relatives. Previously, it was considered the same as the cinnamon giant fantail (Rhipidura fuscorufa), located approximately 135 km (84 mi) east of the Tanimbar Islands.

Merry Fantail (Lipidula laguceria) November 2022. Image credit: James A. Eaton.

Known as a small insectivorous songbird from the Rhipidura fuscorufa family, these birds are native to the Lingidae.

This species measures approximately 18 cm (7 inches) in length, recognized for its cinnamon tail and underparts, as well as its characteristic tail-spreading behavior typical of fantails.

The Rhipidura fuscorufa was first identified in 1883 on the Tanimbar Islands. However, specimens from the Babar group, about 80 miles west, were later examined and previously considered to belong to the same species, a view that persisted for over 120 years.

“Rhipidura fuscorufa is endemic to Indonesia and resides on Tanimbar Island and the Babar Island Group,” said Dr. James Eaton from Bird Tours Asia Limited and Dr. Alex Berryman from BirdLife International.

“Initially described in 1883 based on specimens from the Tanimbar Islands, 15 years later, Rhipidura fuscorufa specimens collected from Babar Island were also examined. Scientists concluded in 1901 that the Babar specimens were consistent with those from the Tanimbar Islands.

For approximately 120 years, the common taxonomic classification was Rhipidura fuscorufa as a monotypic species.

Dr. Eaton first noticed differences in vocalizations between the Babar and Tanimbar populations during a visit in 2011, suggesting the presence of an as-yet undetected species.

To confirm this, authors analyzed 19 specimens at the American Museum of Natural History in New York and the Tring Museum of Natural History in the UK, along with 18 audio recordings from both island groups.

The researchers observed subtle physical differences; Babar birds exhibited darker upper bodies and less pronounced cinnamon underparts compared to Tanimbar birds, while wing, tail, beak, and leg measurements showed no significant variation.

However, the song of the two Rhipidura fuscorufa populations varied considerably.

“The calls of the Babar birds typically consist of single whistles that increase in pitch, whereas Tanimbar calls include varying lengths of whistles for a more rhythmic effect,” they stated. “Though the lengths of strophes are similar, Tanimbar songs feature more notes and shorter intervals between them.”

Cinnamon Giant Fantail (Rhipidura fuscorufa) November 2022. Image credit: James A. Eaton.

Over several years, scientists conducted 132 reproduction experiments during visits to Babar and Tanimbar islands.

Both populations responded to their respective recordings but ignored the songs from the other islands. The study revealed that no Babar birds responded to Tanimbar songs, and vice versa.

“Despite being currently classified as monotypic, our research displays distinct differences between the Tanimbar and Babar populations of Rhipidura fuscorufa,” noted the researchers.

“Morphologically, the two populations have subtle differences in coloration, while the vocalizations are markedly distinct, providing strong evidence that these vocal differences act as a reproductive barrier.”

“Based on this, we propose that Rhipidura fuscorufa populations in the Babar Islands should be taxonomically separated from those in the Tanimbar Islands.”

“While we lack an established name for the Babar population, we describe it as Lipidula laguceria.”

Both the newly identified Lipidula laguceria and its relative Rhipidura fuscorufa are currently listed as Near Threatened under conservation standards, as they adapt well to degraded habitats rather than dense forests.

“Rhipidura fuscorufa is listed as Near Threatened on the IUCN Red List,” the scientists stated.

“Following this classification, both Rhipidura fuscorufa and Lipidula laguceria now have a more restricted range, fulfilling criteria for potential threat listings under IUCN Red List criteria B1 and B2.”

“However, both species demonstrate resilience to habitat degradation and are often found in modified habitats, open areas, and even scrubland with tall mango trees.”

“Indeed, both fantail species appear to prefer highly altered habitats over closed-canopy forests.” Therefore, neither species meets the criteria for being listed as B1 or B2 and should continue to be classified as Near Threatened.”

The discovery of Lipidula laguceria is detailed in a research paper published this month in the British Ornithologists Club Newsletter.

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James A. Eaton and Alex J. Berryman. 2026. A mysterious new species of fantail from the Babar Islands, Maluku Province, Indonesia. British Ornithologists Club Newsletter 146 (2): 203-215; doi: 10.25226/bboc.v146i2.2026.a6