Abstract
We present here a taxonomic treatment of Croton sect. Lasiogyne occurring in Brazil. This study is based on field collections and analyses of more than 1,300 specimens held in 47 herbaria. Eleven species are recorded in Brazil, occurring in almost all phytogeographic domains (except the Pampa). Six species of those species are endemic to that country (Croton blanchetianus, C. claussenianus, C. compressus, C. jacobinensis, C. limae, and C. suassunae). The total absence of extrafloral nectaries and reduplicate-valvate sepals, or valvate sepals, are proposed here as morphological characteristics for the recognition of Brazilian species of the section Lasiogyne. The main characters used to differentiate the species are: branching pattern, stipule shape, venation, trichome type, shape of the sepals of the pistillate flower, shape and number of ramifications of the style, capsule shape, and seed surface texture. Croton macrocalyx is excluded here from this section and positioned in C. sect. Barhamia.
References
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Berry, P.E., Hipp, A.L., Wurdack, K.J., van Ee, B. & Riina, R. (2005) Molecular phylogenetics of the giant genus Croton and tribe Crotoneae (Euphorbiaceae sensu stricto) using ITS and trnL-trnF DNA sequence data. American Journal of Botany 92: 1520–1534. https://doi.org/10.3732/ajb.92.9.1520
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Caruzo, M.B.R. & Cordeiro, I. (2007) Sinopse da tribo Crotoneae Dumort. (Euphorbiaceae s.s.) no Estado de São Paulo, Brazil. Hoehnea 34: 571–585. http://dx.doi.org/10.1590/S2236-89062007000400011
Caruzo, M.B.R., Secco, R.S., Medeiros, D., Riina, R., Torres, D.S.C., Santos, R.F.D., Pereira, A.P.N., Rossine, Y., Lima, L.R., Muniz Filho, E. & Valduga, E. (2020) Croton in Flora e Funga do Brasil. Jardim Botânico do Rio de Janeiro. Available from: https://floradobrasil.jbrj.gov.br/FB17497 (accessed 10 May 2022)
Croizat, L. (1944) Additions to the genus Croton L. in South America. Darwiniana 6: 442–468.
Frodin, D.G. (2004) History and concepts of big plant genera. Taxon 53 (3): 753–776. https://doi.org/10.2307/4135449
Gomes, A.P.S. (2006) Revisão das espécies sul-americanas de Croton L. subgen. Croton sect. Argyroglossum Baill. (Crotonoideae - Euphorbiaceae). Tese de Doutorado. Universidade Federal Rural de Pernambuco, 156 pp.
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Johnston, J.R. (1905) New plants from the Islands of Margarita and Coche, Venezuela. Proceedings of the American Academy of Arts and Sciences 40: 681–698.
Klotzsch, J.F. (1841) Die Crotoneae der Flora von Nord-Amerika. Archiv für Naturgeschichte 7: 250–255.
Klotzsch, J.F. (1843a) Euphorbiaceae. Beitrage zur Botanik Gesammelt auf eine reise um die erde. Novorum Actorum Academiae Caesareae Leopoldino-Carolinae Naturae Curiosum 19 (Suppl. 1): 418–421.
Klotzsch, J.F. (1843b) Euphorbiaceae. In: Bentham, G. Contributions towards a Flora of South America—Enumeration of Plants Collected by Mr. Schomburgk, in British Guiana. London Journal of Botany 2: 42–52.
Kuntze, C.E.O. (1891) Revisio Generum Plantarum 2. Arthur Felix, Leipzig, pp. 375–1011.
Lamarck, J.B.A.P.M. (1786) Encyclopedie Methodique Botanique 2. Chez Pankoucke, Paris, 774 pp.
Linnaeus, C. (1753) Species Plantarum. Laurentius Salvius, Stockholm, 1200 pp.
Lucena, M.F.A. & Sales, M.F. (2006) Tricomas foliares em espécies de Croton L. (Crotonoideae-Euphorbiaceae). Rodriguésia v. 57 (1): 11–25. https://doi.org/10.1590/2175-7860200657102
Luján, M., León, Y. & Riina, R. (2015) Synopsis of Croton (Euphobiaceae) in the Andes of Mérida, Venezuela. Caldasia 37 (1): 73–90. https://doi.org/10.15446/caldasia/v37n1.50815
Martius, C.F.P. (1837) Herbarium Florae Brasiliensis. Flora (Jena) 20 (2): 73–128.
Müller Argoviensis, J. (1865) Euphorbiaceae. Vorläufige Mittheilungen aus dem für De Candolle’s Prodromus bestimmten Manuscript über diese Familie. Linnaea 34: 1–224.
Müller Argoviensis, J. (1866) Euphorbiaceae excl. Euphorbieae. In: Candolle, A.L.P.P. de (Ed.) Prodromus Systematis Naturalis Regni Vegetabilis 15(2). Masson, Paris, pp. 511–1260.
Müller Argoviensis, J. (1873) Euphorbiaceae. In: Martius, C.F.P. von & Eichler, A.W. (Eds.) Flora brasiliensis vol. 11 (2). F. Fleischer, Wien & Leipzig, 751 pp.
Oliveira, A.S., Senna, L.M., Pena, E.M. & Alves, M.V.S. (1989) Euphorbiaceae Juss.—Espécies ocorrentes nas restingas do estado do Rio de Janeiro, Brasil. Acta Botanica Brasilica 3: 131–139. https://doi.org/10.1590/S0102-33061989000300013
Pax, F. (1897) Euphorbiaceae. In: Engler, H.G.A. & Prantl, K.A.E. (Eds.) Die natürlichen Pflanzenfamilien, Nachtrag und Register zu Teil II–IV. Engelmann, Leipzig, 380 pp.
QGIS Development Team (2020) QGiS Geographic information System. Open Source Geospatial Foundation Project. Available from: https://qgis.org/en/site/ (accessed January 2021)
Radcliffe-Smith, A. & Govaerts, R.H.A. (1997) New names and combinations in the Crotonoideae. Kew Bulletin 52: 183–189. https://doi.org/10.2307/4117851
Radford, A.E., Dickson, W.C., Massey, J.R. & Bell, C.R. (1974) Vascular Plant Systematics. Harper & Row Publishers, New York, 891 pp.
Rossine, Y., Gomes, A.P.S., Melo, A.L., Athiê-Souza, S.M. & Sales, M.F. (2020a) Croton suassunae (Euphorbiaceae): A new dioecious species from Northeastern Brazil. Systematic Botany 45: 249–253. https://doi.org/10.1600/036364420X15862837791366
Rossine, Y., Athiê-Souza, S.M., Melo, A.L. & Sales, M.F. (2020b) Rediscovery and lectotypification of Croton claussenianus (Euphorbiaceae), an enigmatic endemic species from southeastern Brazil. Phytotaxa 442 (4): 291–300. https://doi.org/10.11646/phytotaxa.442.4.3
Rossine, Y., Melo, A.L., Athiê-Souza, S.M. & Sales, M.F. (2021) Taxonomic updates in Brazilian species of Croton sect. Lasiogyne (Euphorbiaceae): new synonyms and lectotypifications. Phytotaxa 490 (1): 82–90. https://doi.org/10.11646/phytotaxa.490.1.7
Sá-Haiad, B. (1987) Taxonomia e morfologia das espécies do gênero Croton L. seção Croton, subseção Lasiogyne (Klotzsch) Müll. Arg., série Gonocladium (Baill.) Müll. Arg. ocorrentes em restingas do estado do Rio de Janeiro. Dissertação de Mestrado, Rio de Janeiro. 92 pp.
Santos, R.F., Riina, R. & Caruzo, M.B.R. (2017) Diversity of arborescent lineages of Crotoneae (Euphorbiaceae) in the Brazilian Atlantic Rain Forest. Plant Systematics and Evolution 303 (10): 1467–1497. https://doi.org/10.1007/s00606-017-1441-8
Secco, R.S., Cordeiro, I., Senna-Vale, L., Sales, M.F., Lima, L.R., Medeiros, D., Sá-Haiad, B., Oliveira, A.S.D., Caruzo, M.B.R., Carneiro-Torres, D.S. & Bigio, N.C. (2012) An overview of recent taxonomic studies on Euphorbiaceae s.l. in Brazil. Rodriguésia v. 63 (1): 227–242. https://doi.org/10.1590/S2175-78602012000100014
Silva, J.S., Sales, M.F., Gomes, A.P.S. & Carneiro-Torres, D.S. (2010) Sinopse das espécies de Croton L. (Euphorbiaceae) no estado de Pernambuco, Brasil. Acta Botanica Brasilica v. 24 (2): 441–453. https://doi.org/10.1590/S0102-33062010000200015
Sprengel, C.P.J. (1826) Systema Vegetabilium ed. 16, vol. 3. Sumtibus Librariae Dieterichianae, Göttingen, 936 pp.
Swartz, O.M.D. (1800) Flora Indiae Occidentalis: aucta atque illustrata sive descriptiones plantarum in prodromo recensitarum, vol. 2. Erlangae, Stockholm, 1230 pp.
Thiers, B. (2023, continuously updated) Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Available from: http://sweetgum.nybg.org/science/ih/ (accessed 9 July 2020)
van Ee, B.W. (2011) The contribution of Johann Friedrich Klotzsch to the taxonomy of Croton (Euphorbiaceae) and associated genera. Willdenowia 41: 15–33. https://doi.org/10.3372/wi.41.41102
van Ee, B.W. & Berry, P.E. (2009) A phylogenetic and taxonomic review of Croton (Euphorbiaceae s.s.) on Jamaica including the description of Croton jamaicensis, a new species of section Eluteria. Systematic Botany v. 34 (1): 129–140. https://doi.org/10.1600/036364409787602203
van Ee, B.W., Riina, R. & Berry, P.E. (2011) A revised infrageneric classification and molecular phylogeny of New World Croton (Euphorbiaceae). Taxon 60: 791–823. https://doi.org/10.1002/tax.603013
Webster, G.L. (1993) A provisional synopsis of the sections of the genus Croton (Euphorbiaceae). Taxon 42: 793–823. https://doi.org/10.2307/1223265
Webster, G.L., Del-Arco-Aguillar, M.J. & Smith, B.A. (1996) Systematic distribution of foliar trichome types in Croton (Euphorbiaceae). Botanical Journal of the Linnean Society 121: 41–57. https://doi.org/10.1111/j.1095-8339.1996.tb00744.x
Baillon, H.E. (1858) Étude générale du groupe des Euphorbiacées. Librairie de Victor Masson et fils, Paris, 684 pp.
Baillon, H.E. (1864) Species Euphorbiacearum. Euphorbiacées Américaines. Première partie: Amérique austro-orientale. Adansonia 4: 257–377.
Berry, P.E., Hipp, A.L., Wurdack, K.J., van Ee, B. & Riina, R. (2005) Molecular phylogenetics of the giant genus Croton and tribe Crotoneae (Euphorbiaceae sensu stricto) using ITS and trnL-trnF DNA sequence data. American Journal of Botany 92: 1520–1534. https://doi.org/10.3732/ajb.92.9.1520
Berry, P.E., Kainulainen, K., van Ee, B.W. (2017) A Nomenclator of Croton (Euphorbiaceae) in Madagascar, the Comoros Archipelago, and the Mascarene Islands. PhytoKeys 90: 1–87. https://doi.org/10.3897/phytokeys.90.20586
BFG – The Brazil Flora Group (2021) Brazilian Flora 2020: Leveraging the power of a collaborative scientific network. Taxon 71 (1): 178–198. https://doi.org/10.1002/tax.12640
Carneiro-Torres, D.S. (2009) Diversidade de Croton L. (Euphorbiaceae) no bioma Caatinga. Tese de Doutorado. Universidade Estadual de Feira de Santana. Feira de Santana, Bahia, Brasil.
Caruzo, M.B.R. & Cordeiro, I. (2007) Sinopse da tribo Crotoneae Dumort. (Euphorbiaceae s.s.) no Estado de São Paulo, Brazil. Hoehnea 34: 571–585. http://dx.doi.org/10.1590/S2236-89062007000400011
Caruzo, M.B.R., Secco, R.S., Medeiros, D., Riina, R., Torres, D.S.C., Santos, R.F.D., Pereira, A.P.N., Rossine, Y., Lima, L.R., Muniz Filho, E. & Valduga, E. (2020) Croton in Flora e Funga do Brasil. Jardim Botânico do Rio de Janeiro. Available from: https://floradobrasil.jbrj.gov.br/FB17497 (accessed 10 May 2022)
Croizat, L. (1944) Additions to the genus Croton L. in South America. Darwiniana 6: 442–468.
Frodin, D.G. (2004) History and concepts of big plant genera. Taxon 53 (3): 753–776. https://doi.org/10.2307/4135449
Gomes, A.P.S. (2006) Revisão das espécies sul-americanas de Croton L. subgen. Croton sect. Argyroglossum Baill. (Crotonoideae - Euphorbiaceae). Tese de Doutorado. Universidade Federal Rural de Pernambuco, 156 pp.
Gomes, A.P.S., Sales, M.F. & Melo, A.L. (2010a) Novidades taxonômicas em Croton sect. Argyroglossum Baill. e C. sect. Lasiogyne Klotzsch (Crotonoideae-Euphorbiaceae). Acta Botanica Brasilica 24: 905–908. http://dx.doi.org/10.1590/S0102-33062010000400004
Gomes, A.P.S., Sales, M.F. & Berry, P.E. (2010b) Croton limae (Euphorbiaceae), a new species of section Argyroglossum from northeastern Brazil. Brittonia 62: 206–209. https://doi.org/10.1007/s12228-010-9127-3
Gomes, A.P.S., Melo, A.L., Bezerra, Y.R.L., Athiê-Souza, S.M., Loiola, M.I.B. & Sales, M.F. (2018) Tricomas foliares em sete espécies de Croton sect. Lasiogyne (Klotzsch) Baill. ocorrentes no Brasil (Euphorbiaceae). Revista Nordestina de Biologia 26 (1): 151–160. https://doi.org/10.22478/ufpb.2236-1480.2018v26n1.46183.
Gray, A. (1856) A Manual of the Botany of the Northern United States. Ed. 2. George P. Putnam & Co., New York, 739 pp.
Grisebach, A.H.R. (1859) Flora of the British West Indian Islands. L. Reeve, London, 96 pp.
Humboldt, A.V., Bonpland, A.J.A. & Kunth, C.S. (1817) Nova Genera et Species Plantarum 2. Sumtibus Librariae Graeco-Latino-Germanico, Lutetiae Parisiorum [Paris], 401 pp.
IBGE—Instituto Brasileiro de Geografia e Estatística (2012) Manual Técnico da Vegetação Brasileira. 2nd ed. Instituto Brasileiro de Geografia e Estatística, Rio de Janeiro, 272 pp.
IUCN (2001) Guidelines for using the IUCN red list categories and criteria. Version 11. Gland, Switzerland and Cambridge, U. K.: Standards and Petitions Subcommittee of the IUCN Species Survival Commission. Available from: http://www.iucnredlist.org/documents/RedListGuidelines.pdf (accessed January 2021)
Johnston, J.R. (1905) New plants from the Islands of Margarita and Coche, Venezuela. Proceedings of the American Academy of Arts and Sciences 40: 681–698.
Klotzsch, J.F. (1841) Die Crotoneae der Flora von Nord-Amerika. Archiv für Naturgeschichte 7: 250–255.
Klotzsch, J.F. (1843a) Euphorbiaceae. Beitrage zur Botanik Gesammelt auf eine reise um die erde. Novorum Actorum Academiae Caesareae Leopoldino-Carolinae Naturae Curiosum 19 (Suppl. 1): 418–421.
Klotzsch, J.F. (1843b) Euphorbiaceae. In: Bentham, G. Contributions towards a Flora of South America—Enumeration of Plants Collected by Mr. Schomburgk, in British Guiana. London Journal of Botany 2: 42–52.
Kuntze, C.E.O. (1891) Revisio Generum Plantarum 2. Arthur Felix, Leipzig, pp. 375–1011.
Lamarck, J.B.A.P.M. (1786) Encyclopedie Methodique Botanique 2. Chez Pankoucke, Paris, 774 pp.
Linnaeus, C. (1753) Species Plantarum. Laurentius Salvius, Stockholm, 1200 pp.
Lucena, M.F.A. & Sales, M.F. (2006) Tricomas foliares em espécies de Croton L. (Crotonoideae-Euphorbiaceae). Rodriguésia v. 57 (1): 11–25. https://doi.org/10.1590/2175-7860200657102
Luján, M., León, Y. & Riina, R. (2015) Synopsis of Croton (Euphobiaceae) in the Andes of Mérida, Venezuela. Caldasia 37 (1): 73–90. https://doi.org/10.15446/caldasia/v37n1.50815
Martius, C.F.P. (1837) Herbarium Florae Brasiliensis. Flora (Jena) 20 (2): 73–128.
Müller Argoviensis, J. (1865) Euphorbiaceae. Vorläufige Mittheilungen aus dem für De Candolle’s Prodromus bestimmten Manuscript über diese Familie. Linnaea 34: 1–224.
Müller Argoviensis, J. (1866) Euphorbiaceae excl. Euphorbieae. In: Candolle, A.L.P.P. de (Ed.) Prodromus Systematis Naturalis Regni Vegetabilis 15(2). Masson, Paris, pp. 511–1260.
Müller Argoviensis, J. (1873) Euphorbiaceae. In: Martius, C.F.P. von & Eichler, A.W. (Eds.) Flora brasiliensis vol. 11 (2). F. Fleischer, Wien & Leipzig, 751 pp.
Oliveira, A.S., Senna, L.M., Pena, E.M. & Alves, M.V.S. (1989) Euphorbiaceae Juss.—Espécies ocorrentes nas restingas do estado do Rio de Janeiro, Brasil. Acta Botanica Brasilica 3: 131–139. https://doi.org/10.1590/S0102-33061989000300013
Pax, F. (1897) Euphorbiaceae. In: Engler, H.G.A. & Prantl, K.A.E. (Eds.) Die natürlichen Pflanzenfamilien, Nachtrag und Register zu Teil II–IV. Engelmann, Leipzig, 380 pp.
QGIS Development Team (2020) QGiS Geographic information System. Open Source Geospatial Foundation Project. Available from: https://qgis.org/en/site/ (accessed January 2021)
Radcliffe-Smith, A. & Govaerts, R.H.A. (1997) New names and combinations in the Crotonoideae. Kew Bulletin 52: 183–189. https://doi.org/10.2307/4117851
Radford, A.E., Dickson, W.C., Massey, J.R. & Bell, C.R. (1974) Vascular Plant Systematics. Harper & Row Publishers, New York, 891 pp.
Rossine, Y., Gomes, A.P.S., Melo, A.L., Athiê-Souza, S.M. & Sales, M.F. (2020a) Croton suassunae (Euphorbiaceae): A new dioecious species from Northeastern Brazil. Systematic Botany 45: 249–253. https://doi.org/10.1600/036364420X15862837791366
Rossine, Y., Athiê-Souza, S.M., Melo, A.L. & Sales, M.F. (2020b) Rediscovery and lectotypification of Croton claussenianus (Euphorbiaceae), an enigmatic endemic species from southeastern Brazil. Phytotaxa 442 (4): 291–300. https://doi.org/10.11646/phytotaxa.442.4.3
Rossine, Y., Melo, A.L., Athiê-Souza, S.M. & Sales, M.F. (2021) Taxonomic updates in Brazilian species of Croton sect. Lasiogyne (Euphorbiaceae): new synonyms and lectotypifications. Phytotaxa 490 (1): 82–90. https://doi.org/10.11646/phytotaxa.490.1.7
Sá-Haiad, B. (1987) Taxonomia e morfologia das espécies do gênero Croton L. seção Croton, subseção Lasiogyne (Klotzsch) Müll. Arg., série Gonocladium (Baill.) Müll. Arg. ocorrentes em restingas do estado do Rio de Janeiro. Dissertação de Mestrado, Rio de Janeiro. 92 pp.
Santos, R.F., Riina, R. & Caruzo, M.B.R. (2017) Diversity of arborescent lineages of Crotoneae (Euphorbiaceae) in the Brazilian Atlantic Rain Forest. Plant Systematics and Evolution 303 (10): 1467–1497. https://doi.org/10.1007/s00606-017-1441-8
Secco, R.S., Cordeiro, I., Senna-Vale, L., Sales, M.F., Lima, L.R., Medeiros, D., Sá-Haiad, B., Oliveira, A.S.D., Caruzo, M.B.R., Carneiro-Torres, D.S. & Bigio, N.C. (2012) An overview of recent taxonomic studies on Euphorbiaceae s.l. in Brazil. Rodriguésia v. 63 (1): 227–242. https://doi.org/10.1590/S2175-78602012000100014
Silva, J.S., Sales, M.F., Gomes, A.P.S. & Carneiro-Torres, D.S. (2010) Sinopse das espécies de Croton L. (Euphorbiaceae) no estado de Pernambuco, Brasil. Acta Botanica Brasilica v. 24 (2): 441–453. https://doi.org/10.1590/S0102-33062010000200015
Sprengel, C.P.J. (1826) Systema Vegetabilium ed. 16, vol. 3. Sumtibus Librariae Dieterichianae, Göttingen, 936 pp.
Swartz, O.M.D. (1800) Flora Indiae Occidentalis: aucta atque illustrata sive descriptiones plantarum in prodromo recensitarum, vol. 2. Erlangae, Stockholm, 1230 pp.
Thiers, B. (2023, continuously updated) Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Available from: http://sweetgum.nybg.org/science/ih/ (accessed 9 July 2020)
van Ee, B.W. (2011) The contribution of Johann Friedrich Klotzsch to the taxonomy of Croton (Euphorbiaceae) and associated genera. Willdenowia 41: 15–33. https://doi.org/10.3372/wi.41.41102
van Ee, B.W. & Berry, P.E. (2009) A phylogenetic and taxonomic review of Croton (Euphorbiaceae s.s.) on Jamaica including the description of Croton jamaicensis, a new species of section Eluteria. Systematic Botany v. 34 (1): 129–140. https://doi.org/10.1600/036364409787602203
van Ee, B.W., Riina, R. & Berry, P.E. (2011) A revised infrageneric classification and molecular phylogeny of New World Croton (Euphorbiaceae). Taxon 60: 791–823. https://doi.org/10.1002/tax.603013
Webster, G.L. (1993) A provisional synopsis of the sections of the genus Croton (Euphorbiaceae). Taxon 42: 793–823. https://doi.org/10.2307/1223265
Webster, G.L., Del-Arco-Aguillar, M.J. & Smith, B.A. (1996) Systematic distribution of foliar trichome types in Croton (Euphorbiaceae). Botanical Journal of the Linnean Society 121: 41–57. https://doi.org/10.1111/j.1095-8339.1996.tb00744.x