Phylogenetic analysis has shown that the ground warblers (Robsonius) are the sister-group of all other species of Locustellidae, which in turn consists of two major clades. This suggests that three subfamilies may be recognised: Locustellinae new rank, comprising the genera Helopsaltes and Locustella, Megalurinae new rank, comprising the genera Poodytes, Malia, Cincloramphus, Megalurus, Elaphrornis, Schoenicola, Catriscus and Bradypterus, and another, monotypic subfamily comprising the genus Robsonius, for which we introduce the name Robsoniinae.

Recent advances in our understanding of the Bolivian avifauna have been substantial; 1,452 species are now known for the country. This manuscript presents a compilation of records made between 2005 and the present, including records for 27 species that contribute to our understanding of elevational and geographic distributions and status of birds in Bolivia. Among the most noteworthy discoveries are further records of the only recently recorded Coscoroba Swan Coscoroba coscoroba, the first record of the globally threatened Horned Curassow Pauxi unicornis in Santa Cruz for more than a decade, evidence that Scaled Dove Columbina squamata might be becoming established in the east of the country, the second record of South American Painted Snipe Nycticryphes semicollaris in Bolivia, the fifth and sixth Bolivian records of Common Tern Sterna hirundo and the third national record of Purple-throated Cotinga Porphyrolaema porphyrolaema. These findings underscore the need for sustained research and documentation of Bolivia's avifauna.

We describe the population of Slate-crowned Antpitta Grallaricula nana in the northern section of the main East Andean range in Colombia and Venezuela (from Tamá to Páramo de Santurbán) as a new subspecies. Vocally, this population is differentiated from the previously consubspecific G. n. nanitaea of the Mérida Andes in Venezuela above the traditional 75% threshold for subspecies, with on average fewer notes, shorter song length, slower song speed, reduced change in acoustic frequency, lower max. acoustic frequency of the highest note and longer note length at the start of the song. Recently published molecular studies are also consistent with its treatment as a separate subspecies. Morphological differentiation is slight, but the Tamá-Santurbán population appears to have a paler breast in females, more extensive white feathering on the belly in males and a slightly broader bill than Mérida birds. The new subspecies is separated by the Chicamocha, Suárez and Sogamoso Valleys from the nominate subspecies of the southern East Andes and hallsi of the Serranía de los Yariguíes, both of which are more clearly differentiated in both voice and plumage.

Firewood gatherer Anumbius annumbi is a furnariid endemic to southern South America that occurs in grassland, agricultural areas, shrubland, savanna, and open woodland. I report the first record of the species for Bolivia in Parque Nacional y Área Natural de Manejo Integrado Otuquis in September 2024.

Spot-backed Puffbird Nystalus maculatus is widely distributed across eastern South America but its breeding biology is poorly known. We present the first detailed observations on the nest, eggs, nestlings and their development, made in Maranhão, Brazil. Nests are tunnel-shaped, averaging 7.0 ± 1.0 cm wide and 111.0 ± 26.8 cm long (n = 11), excavated in sandy soil in sloping terrain, ending in an egg chamber. Clutches comprise 2–4 unmarked white eggs, mean 25.36 ± 12.36 × 20.82 ± 10.17 mm, mass 5.55 ± 2.74 g (n = 7). Nestlings hatch naked with closed eyes and the nestling period occupies 21–22 days. Nest predators included Crab-eating Fox Cerdocyon thous, domestic dog Canis lupus familiaris and Common Tegu Salvator merianae.

The ‘plates’ (intaglio prints) of Alexander Wilson’s nine-volume work, American ornithology (1808–14), collectively depicted hundreds of individual bird specimens including the types of many new species—or so scholars have long assumed. Here, by reconstructing the modified intaglio process used by Wilson and his team, I demonstrate that many (probably most) of his figures were composite in nature, combining anatomical details copied from multiple specimens, sometimes even multiple species. This phenomenon has been universally overlooked by historians and ornithologists, despite its critical implications for understanding Wilson’s taxonomy and nomenclature.

A 19th-century specimen of Black-bellied Storm Petrel Fregetta tropica in the collection of the Natural History Museum, Tring is putatively from Port Essington, an inlet on the Coburg Peninsula in Northern Territory, Australia, where there was a colonial-period settlement. There are no other records from the seas off northern Australia except east of the Torres Strait. Previous assessments of the avifauna of the Northern Territory have suggested that the identity or locality of the specimen should be questioned. We examined the specimen, verified that it is F. tropica, and determined that it was collected by the well-known natural historian John Gilbert, probably in 1840 or 1841, and probably in Northern Territory waters. This specimen therefore represents a notable vagrant and the first (and only) record of Black-bellied Storm Petrel for Northern Territory.

A recent proposal to treat Ayeyarwady Broadbill Cymbirhynchus [macrorhynchos] affinis of south-west Myanmar as a species separate from Black- and-red Broadbill C. macrorhynchos has failed to garner widespread support. Here we compare six specimens of affinis with a large series of C. macrorhynchos and glean what information we can from specimen data and the literature about this poorly known taxon's distribution and conservation status. C. affinis differs in being 10–17% smaller, with a 22% shallower bill, and having elongate crimson spots on the tertials, a much larger white wing spot, paler and brighter red on the underparts and rump, and broader and more extensive white subterminal tail tips. In our view these characters, which represent abrupt and profound differences across a trivial distance from the nearest population of the wide-ranging and (as we argue) probably monotypic C. macrorhynchos, uphold species rank for the taxon. However, we can find no record of it since 1874. It may once have occurred throughout the Ayeyarwady Delta, where it may now be extirpated due to the near-total loss of suitable habitat. It has also been recorded in the Rakhine Yoma (Arakan Hills) up to an elevation of at least 750 m, where suitable habitat remains, although recent (untargeted) field work has not found it there. However, the meagre evidence for its former range and status is disconcertingly inconsistent. We recommend that Ayeyarwady Broadbill be listed on the IUCN Red List as Data Deficient.