Olyra Linnaeus (1759: 1261)

Lopes-Neto, Raimundo Balieiro & Viana, Pedro Lage, 2022, Flora of the Serra do Cachimbo (Eastern Amazon, Brazil): Bambusoideae (Poaceae), including the description of two new species, Phytotaxa 550 (2), pp. 99-129 : 114-115

Olyra Linnaeus (1759: 1261) .

TYPE:— Olyra latifolia Linnaeus (1759: 1261) .

Plants cespitose. Culms homomorphic (dimorphic in O. ecaudata ), erect or climbing, leaning in the vegetation, 2– 4 m tall, infra- and supranodal bands of trichomes absent, unbranched at the lower and median nodes, branched at the upper nodes to produce synflorescences, without thorns. Leaves not differentiated into culm leaves and foliage leaves. Leaf sheaths without fimbriae at the apex, translucent swelling absent, outer ligule absent, blades ovate-lanceolate or lanceolate, midnerve not prominent. Synflorescences terminal, typical panicles, composed of 2-8 conjugate branches, the lower branches with male spikelets and with or without terminal female spikelets, the upper branches with male spikelets below and 1–8 terminal female spikelets; spikelets with pedicels clavate to subclavate, solitary and unisexual, glumes 2 (female spikelets) or absent (male spikelets), anthecium smooth or with small excavations. Fruit a basic caryopsis, hilum linear, as long as the caryopsis.

Olyra is an herbaceous bamboo genus mainly characterized by the erect or climbing culms, 2–4 m tall, ovatelanceolate to lanceolate leaves and synflorescences a terminal panicle, bearing male and female spikelets on the same synflorescence, with female spikelets 7.3–32 mm long and the pedicels clavate to subclavate ( Soderstrom & Zuloaga 1989). The genus has 24 species in Central and South America ( Kellogg 2015). In Brazil, twenty species occur in the Amazon, Caatinga, Cerrado, Mata Atlântica and Pampas ( Oliveira et al. 2020b). In Serra do Cachimbo, Olyra is represented by four species.

Identification key to the species of Olyra from the Serra do Cachimbo, Eastern Amazon, Brazil.

1. Culms dimorphic, vegetative culms with 5–7 leaves clustered in the apex, sheath sparsely pilose, flowering culms with leaves bladeless, sheaths glabrous.......................................................................................................................................... Olyra ecaudata

- Culms homomorphic, leaves distributed along the culms, sheaths glabrous, shortly pilose or pubescent, margins ciliate, shortciliate or densely pubescent................................................................................................................................................................2

2. Leaf blades ovate to oblong-lanceolate; female anthecium fusiform, irregularly pitted with small excavations ................................ ....................................................................................................................................................................................... Olyra taquara

- Leaf blades ovate-lanceolate; female anthecium ovoid, smooth........................................................................................................3

3. Synflorescences umbelliform, each branch with male spikelets on short pedicels basally and a single terminal female spikelet; female spikelets 23–32 × 4–5 mm, glabrous, the glumes subequal, apex awned, the awn 13–14 mm long ....................................... ...................................................................................................................................................................................... Olyra caudata

- Synflorescences pyramidal, the lower branches with male spikelets only, the upper branches with male spikelets below and 1 to many terminal female spikelets; female spikelets 10–12 × 1.4–2.2 mm, glabrous to shortly pilose, the glumes unequal, apex awned, the 3.8–4.8 mm long...................................................................................................................................................... Olyra latifolia