Croton sertanejus, a new species from Seasonally Dry Tropical Forest in Brazil, and redescription of C. echioides (Euphorbiaceae)
Abstract
During a taxonomic study of the species of Croton sect. Adenophylli occurring in Brazil, approximately 140 collections usually identified as Croton echioides, C. rhamnifolius or C. rhamnifolioides caught our attention due to the distinct morphology of vegetative and reproductive organs. After the analysis of these collections, we concluded that they represent a new species, C. sertanejus Sodré & M.J.Silva sp. nov., which was also corroborated by an anatomical study of their leaves. This new species can be differentiated by pseudomonopodial branching, leaves with petioles up to 1.7 cm long, 4–6 subsessile nectary glands and indumentum of sessile trichomes on both surfaces. Detailed descriptions, including details of leaf anatomy, are provided for C. sertanejus sp. nov. and C. echioides, its closely related species. We also formalize the synonymization of C. kalkmannii under C. echioides and re-evaluate the typification of these names, in order to better clarify their taxonomic status.
References
Bachman S., Moat J., Hill A.W., de la Torre J. & Scott B. 2011. Supporting Red List threat assessments with GeoCAT: geospatial conservation assessment tool. ZooKeys 150: 117–126. https://doi.org/10.3897/zookeys.150.2109
Baillon H. 1864. Species Euphorbiacearum. Euphorbiacées Américaines. Première partie: Amérique austro-orientale. Adansonia 4: 257–377.
Barbosa B.L.R., Oliveira R.P., Mascarenhas A.A.S., Dórea M.D.C., Martins F.M. & Carneiro-Torres D.S. 2018. Croton aemulus and C. graomogolensis (Euphorbiaceae): Two new species from Minas Gerais, Brazil, based on distinct lines of evidence and their relation to C. muscicapa and C. longibracteatus. Phytotaxa 365: 259–272. https://doi.org/10.11646/phytotaxa.365.3.4
Berry P.E., Hipp A.L., Wurdack K.J., van Ee B.W. & 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
Bukatsch F. 1972. Bemerkungen zur Doppelfärbung Astrablau-Safranin. Mikrokosmos 61: 255.
Carneiro-Torres D.S. 2009. Diversidade de Croton L. (Euphorbiaceae) no bioma Caatinga. PhD Thesis, Universidade Estadual de Feira de Santana, Feira de Santana.
Caruzo M.B.R., Santos R.F., Feio A.C., Meira R.M.S. & Riina R. 2016. Redefinition of Croton macrobothrys (Euphorbiaceae), a tree species from the Brazilian Atlantic Forest, with the description of a new subspecies. Phytotaxa 273: 51–58. https://doi.org/10.11646/phytotaxa.273.1.5
Caruzo M.B.R., Medeiros D., Santos R.F.D., Pereira A.P.N., Torres D.S.C., Secco R.S., Muniz Filho E., Valduga E., Lima L.R., Riina R. & Rossine Y. 2020. Croton in Flora do Brasil 2020. Jardim Botânico do Rio de Janeiro. Available from http://floradobrasil.jbrj.gov.br/reflora/floradobrasil/FB17497 [accessed 26 Mar. 2021].
Dinerstein E., Olson D., Joshi A., Vynne C., Burgess N.D., Wikramanayake E., Hahn N., Palminteri S., Hedao P., Noss R., Hansen M., Locke H., Ellis E.C., Jones B., Barber C., Hayes R., Kormos C., Martin V., Crist E., Sechrest W., Price L., Baillie J.E.M., Kindt R., Van Breugel P. & Graudal L. 2017. An ecoregion-based approach to protecting half the terrestrial realm. Bioscience 67 (6): 534–545. http://doi.org/10.1093/biosci/bix014
Evert R.F. 2006. Esau’s Plant Anatomy. Meristems, Cells, and Tissues of the Plant Body – Their Structure, Function, and Development. 3rd Ed. J. Wiley & Sons, Hoboken. https://doi.org/10.1002/0470047380
Feio A.C., Meira R.M.S.A. & Riina R. 2018. Leaf anatomical features and their implications for the systematics of dragon’s blood, Croton section Cyclostigma (Euphorbiaceae) Botanical Journal of the Linnean Society 187: 614–632. https://doi.org/10.1093/botlinnean/boy038
Glaziou A.F.M. 1913. Plantae Brasiliae centralis a Glaziou lectae. Mémoires de la Société botanique de France 59 (3g): 611–648.
Govaerts R., Frodin D.G. & Radcliffe-Smith A. 2000. World Checklist and Bibliography of Euphorbiaceae (and Pandaceae). Royal Botanic Gardens, Kew.
Harris J.G. & Harris M.W. 2001. Plant Identification Terminology: An Illustrated Glossary, Second Ed. Spring Lake Publishing, Spring Lake.
IUCN. 2017. Guidelines for Using the IUCN Red List Categories and Criteria. Version 13. Prepared by the Standards and Petitions Subcommittee of the IUCN Species Survival Commission. IUCN, Gland and Cambridge.
Johansen D.A. 1940. Plant Microtechnique. McGraw-Hill, New York.
Kainulainen K., van Ee B., Razafindraibe H. & Berry P.E. 2017. A revision of the Adenophorus Group and other glandular-leaved species of Croton (Euphorbiaceae) from northern Madagascar and Mayotte, including three new species. Candollea 72 (2): 371–402. https://doi.org/10.15553/c2017v722a15
Lima L.R. & Pirani J.R. 2003. O gênero Croton L. na Cadeia do Espinhaço, Minas Gerais, Brasil. Boletim de Botânica da Universidade de São Paulo 21: 299–344. https://doi.org/10.11606/issn.2316-9052.v21i2p299-344
Metcalfe C.R. & Chalk L. 1979. Anatomy of the Dicotyledons: Systematic Anatomy of the Leaf and Stem. Vol. 1, 2nd Ed. Oxford University Press, Oxford.
Metcalfe C.R. & Chalk L. 1983. Anatomy of the Dicotyledons. Vol. 2, 2nd Ed. Clarendon Press, Oxford.
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. In: de Candolle A. (ed.) Prodromus sytematis naturalis regni vegetabilis 15: 189–1261.
Radford A.E., Dickison W.C., Massey J.R. & Bell C.R. 1974. Vascular Plant Systematics. Harper & Row Publishers, New York.
Riina R. & Berry P.E. 2010. Two new South American species of Croton (Euphorbiaceae) and their phylogenetic affinities. Anales del Jardín Botánico de Madrid 67 (1): 23–27. https://doi.org/10.3989/ajbm.2243
Rosa A.C, Ferraro A., Silva R.H., Pott V.J., Victório C.P. & Arruda R.C.O. 2021. Leaf anatomy of two medicinal Croton species: Contribution to plant recognition. Microscopy Research and Technique 84: 1–11. https://doi.org/10.1002/jemt.23727
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, Brazil. Acta Botanica Brasilica 24 (2): 441–453. https://doi.org/10.1590/S0102-33062010000200015
Soares D.A. 2013. Morfoanatomia foliar de Espécies de Croton sect. Luntia (Euphorbiaceae) como Contribuição para a Taxonomia do Gênero. MSc Dissertation, Universidade Federal de Viçosa, Viçosa.
Sodré R.C. & Silva M.J. 2020. A taxonomic reassessment of Croton grandivelus, including recognition of a new species, C. insignis, and the redefinition of C. fulvus (Euphorbiaceae). Phytotaxa 472: 207–239. https://doi.org/10.11646/phytotaxa.472.3.1
Sodré R.C., Sales M.F., Berry P.E. & Silva M.J. 2019a. Taxonomic synopsis of Croton section Geiseleria (Euphorbiaceae) in Brazil, including description of a new species. Phytotaxa 417 (1): 1–105. https://doi.org/10.11646/phytotaxa.417.1.1
Sodré R.C., Souza A.O., Alonso A.A. & Silva M.J. 2019b. Molecular, morphological, and anatomical data support a new species of Croton sect. Geiseleria (Crotonoideae, Euphorbiaceae). Plant Systematic and Evolution 305: 233–246. https://doi.org/10.1007/s00606-019-1566-z
Sodré R.C., Alonso A.A. & Silva M.J. 2022. Revised delimitation of Croton campestris (Euphorbiaceae), including description of two new species, molecular phylogenetic, anatomical and micromorphological data. Acta Botanica Brasilica 36: e2021abb0163. https://doi.org/10.1590/0102-33062021abb0163
Thiers B. 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 7 Aug. 2022].
van Ee B.W. & Berry P.E. 2021. Taxonomy of Croton flavens (Euphorbiaceae), a Caribbean endemic, and a preliminary subsectional classification of Croton section Adenophylli. Caribbean Journal of Science 51: 314–357. https://doi.org/10.18475/cjos.v51i2.a14
van Ee B.W., Riina R. & Berry P.E. 2011. A revised infrageneric classification and molecular phylogeny of New World Croton (Euphorbiaceae). Taxon 60 (3): 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 (4): 793–823. https://doi.org/10.2307/1223265
Webster G.L., Del-Arco-Aguilar 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
Copyright (c) 2022 Rodolfo Carneiro Sodré, Marcos José da Silva
This work is licensed under a Creative Commons Attribution 4.0 International License.
Creative Commons Copyright Notices
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License (CC BY 4.0) that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are NOT PERMITTED to post their submitted work online (e.g., in institutional repositories or on personal websites) prior to publication, as it may lead to nomenclatural issues.
