A new Critically Endangered species of stone breaker (Phyllanthus, Phyllanthaceae) from Central Brazil, with notes on its leaf and stem anatomy Author Silva, Marcos José Da 0000-0001-9717-5701 Universidade Federal de Goiás, Instituto de Ciências Biológicas, Departamento de Botânica, CP 131, 74001 - 970, Goiânia, GO, Brazil. & marcos _ agrorural @ hotmail. com; https: // orcid. org / 0000 - 0001 - 9717 - 5701 marcos_agrorural@hotmail.com Author Alonso, Alexandre Antônio 0000-0003-1118-2703 Universidade Federal de Goiás, Instituto de Ciências Biológicas, Departamento de Botânica, CP 131, 74001 - 970, Goiânia, GO, Brazil. & alonsoalx @ yahoo. com. br; https: // orcid. org / 0000 - 0003 - 1118 - 2703 alonsoalx@yahoo.com.br Author Santos, Igor Soares Dos 0000-0002-6067-8409 Universidade Federal de Goiás, Instituto de Ciências Biológicas, Programa de Pós-graduação em Ciências Ambientais, Rua Aroeira, Campus Samambaia, CEP 74690 - 900, Goiânia, GO, Brazil. & igorsoares 1237 @ gmail. com; https: // orcid. org / 0000 - 0002 - 6067 - 8409 igorsoares1237@gmail.com text Phytotaxa 2022 2022-01-06 530 1 53 64 journal article 2742 10.11646/phytotaxa.530.1.4 1c6f4495-9280-4e5b-ba15-d422e8720c43 1179-3163 5823919 Key for identification of Phyllanthus sect. Loxopodium species occurring in Brazil 1. Stems winged, flattened or angled in cross section; leaves chartaceous............................................................................................2 - Stems cylindrical in cross section; leaves thinly membranaceous .....................................................................................................4 2. Stems up to 13 cm tall, winged, hispidulous; leaves 3–6 × 2.9–3 mm , indumented, ciliate at margin; pistillate disk patelliform; flowers on both sexes 5 and 6-merous on the same plant .............................................................................. Phyllanthus pterocaulis - Stems (15) 19–50 cm tall; subcylindrical, angled or flattened, glabrous; leaves 5–15 × 3–6 mm glabrous, non-ciliate at margin; pistillate disk anular or segmented; flowers on both sexes 5 or 6-merous on the same plant............................................................3 3. Plants dioecious; branches flattened; stipules hastate; cymules bisexual; stamens united; pistillate disk entire; capsules 2–2.1 mm long; seeds verruculose..................................................................................................................................... Phyllanthus avicularis - Plants monoecious; branches subcylindrical; stipules oval-triangular; cymules unisexual; stamens free; pistillate disk 5 or 6 segmented; capsules 3–3.1 mm long; seeds smooth .............................................................................. Phyllanthus hyssopifolioides 4. Leaves oblong-obovate, obovate or elliptic-obovate; stipules 0.8–12 mm long; segments of the staminate disk cuneate or rounded; pistillate sepals 1–1.2 mm long, linear-spathulate...................................................... Phyllanthus caroliniensis subsp. caroliniensis - Leaves elliptic; stipules 1.5–2 mm long; segments of the staminate disk oval or elliptic; pistillate sepals 0.7–0.9 mm long, oblong or spathulate.................................................................................................................... Phyllanthus caroliniensis subsp. guianensis