Thismia Griff. Myco-heterotrophic small herbs, typically growing among leaf litter on the shady wet forest floor; root system tuberous or rarely cylindrical, roots filiform; stems unbranched; leaves (2-)4, alternate, scale-like, sometimes forming a rosette just below the flower; flowers terminal, solitary, 5-20 mm long, bisexual, actinomorphic to sometimes zygomorphic, fruit cup-shaped, fleshy; seeds many, small and ‘dustlike’, (narrowly) ellipsoid to ovoid. 108 spp., 84 in tropical and temperate Asia, 24 in the New World, 23 in South America, 20 in Brazil, 13 endemics; two subgenera.
A. subg. Ophiomeris ▸ Neotropical Thismia; 23 spp. in three sections; all species in Brazil except T. saulensis H.Maas & Maas from French Guiana, T. paradisiaca Guzman & Toro and T. andicola Aguilar-Cano, S. Guzman-Guzman & Lopera-Toro from Colombia.
▪ sect. Myostoma ‣ a single species, T. hyalina (Miers) Benth. & Hook.f. ex F.Muell. in Brazil (Acre, Amazonas, Mato Grosso, Pará, Rio de Janeiro and São Paulo states) and Peru.
▪ sect. Ophiomeris ‣ 15 spp., 12 in Brazil, 8 endemics: T. mantiqueirensis Engels & E.C.Smidt., T. janeirensis Warm., and T. macahensis (Miers) F.Muell. are restricteds to São Paulo, Rio de Janeiro and Espírito Santo states in SE Brazil, T. luetzelburgii Goebel & Suess. occur in SE Brazil disjunct in Panamá, T. glaziovii Poulsen disjunct in SE Brazil and SE Colombia, T. prataensis Mancinelli, C.T.Blum & E.C.Smidt and T. cordata D.F.Silva & J.M.A.Braga endemic to Paraná state, SE Brazil, T. variabilis D.F.Silva, Honório & J.M.A.Braga are endemic to Acre state, N Brazil; T. calcarata D. F. Silva, Honorio & J. M. A. Braga in Acre state in Brazil up to Peru; T. panamensis (Standl.) Jonker known in Brazil in Paraná state, also in Bolivia, Ecuador, Colombia, Costa Rica and Panamá, T. violacea D.F.Silva & J.M.A.Braga endemic to Goiás state (Brazil); T. paradisiaca Guzman & Toro and T. andicola Aguilar-Cano, S. Guzman-Guzman & Lopera-Toro endemics to Colombia, and T. saulensis H.Maas & Maas endemic to center French Guiana.
▪ sect. Pyramidalis ‣ 7 spp., all but two endemics to Brazil: T. caudata Maas & H.Maas and T. fungiformis (Taub. ex Warm.) Maas & H.Maas are rare species in SE Brazil; T. melanomitra Maas & H.Maas known from the Ecuador, and Mato Grosso and Pará states in Brazil; T. pseudomelanomitra D.F.Silva & J.M.A.Braga, T. ribeiroi Engels, D. Ferreira-da-Silva & Soares-Lopes and T. petasiformes D.F.Silva & J.M.A.Braga are endemics to N Mato Grosso state in Brazil, in Amazon forest; and T. singeri (de la Sota) Maas & H.Maas is known from Pará and N Mato Grosso in Brazil, Mamore Basin in Bolivia and Napo region of Ecuador.
BRAZILIAN THISMIA'S DIVERSITY DISTRIBUTIONS B. subg. Thismia ‣ 85 spp., one endemic to U.S.A., T. americana N.Pfeiff. collected few times near Chicago, U.S.A. (latter in 1917), remaining 84 in tropical Asia to Australia and Tasmania.
Thismia hyalina (Kamer & Maas, FFESP, 2016; NHM; iNaturalist), T. singeri, T. ribeiroi, T. melanomitra (Silva et al., Phytotyaxa, 2020), T. petasiformis (DF. Silva, Phytotaxa, 2022), T. panamensis (Sousa, CheckList, 2021), T. prataensis (Mancinelli et al., Systematic Botany, 2012), T. cordata (Silva et al., Phytotaxa, 2021), T. caudata, T. espirito-santensis, T. fungiformes, T. macahensis (Plantas Raras do Brasil, UEFS, 2009), T. mantiqueirensis (M.E.Engels, Phytotaxa, 2022). T. janeirensis, T. glaziovii, T. luetzelburgii (Reflora)
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