On 15 June 2018 TNM found an empty hummingbird nest in the understorey of várzea forest c. 56 km downstream of Porto Velho (08°35’33.7”S, 63°34’54.3”W). When revisited on 9 July 2018, the nest contained two nestlings, with their eyes still closed (Fig. 1). After a few minutes, an adult P. hispidus appeared and fed the nestlings. The nest, a funnel-shaped cup, was sited 1.01 m above ground in a Costus (Costaceae) plant (Fig. 1). The cup measured 31 × 52 mm internally, and was 130 mm tall externally, with an elongated ‘tail’ of 70 mm at the base of the cup. The nest comprised fine, pale, dry palm fibres, tightly bound with spider webs, and attached to the underside of a damaged strip of leaf. Overall, the nest’s shape, composition, height and attachment were similar to those of a nest of the species found in June 2016, in Mato Grosso state, Brazil (C. P. Figueiredo; https://www.wikiaves. com/1234488). The elongated leaf of Costus sp. used here, offered a similar substrate to the leaves of understorey palms, which are among the most frequently used nest substrates of the genus Phaethornis (Ruschi 1949, Oniki 1970, Greeney et al. 2018).