Throughout this contribution, overall orchid morphological terms follow Dressler [2 ]. Taxonomic delimitation of Brazilian Epidendrum species follows Pessoa [11 ]. Epidendrum densiflorum locally occurs both as an epiphytic or rupicolous species, always near river courses and streams. The cane-like stems may reach up to 1 m high [12 (link)]. The inflorescences are terminal and may reach up to 40 cm in length. The species has a flowering peak in January to April. A plant voucher is deposited at the ICN Herbarium (R. B. Singer s.n. 19/05/2019). Plant and overall flower features were documented through photos. To locate nectar, ten buds were isolated with tulle and checked for nectar 24 h after opening. A microsyringe CG model 701 RN (5 µL volume) was inserted in the floral cuniculus to pump the nectar (if present). Since no free nectar was found (see Results, Section 2 ), no further analyses (volume, concentration) were possible. Complementary, ten additional fresh, intact flowers were obtained from two specimens and dissected under a stereomicroscope to locate nectar.
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