Out of the mud: two new species of Hippeastrum (Amaryllidaceae) from the Doce and Jequitinhonha River basins, Brazil

Authors: CAMPOS-ROCHA, ANTONIO - Universidade De Campinas (UNICAMP); MEEROW, ALAN - Retired ARS Employee; MACHADO, RAQUEL - Universidade De Campinas (UNICAMP); MAYER, JULIANA - Universidade De Campinas (UNICAMP); DA MOTA, RUBENS - Mining Institute Of Agriculture; FONTANA, ANDRE - Universidade Federal Do Vale Do São Francisco; RIBEIRO, OTAVIO - Universidade Federal De Vicosa; GARCIA, NICOLAS - Universidad De Chile; DUTILH, JULIE - Universidade De Campinas (UNICAMP)

Submitted to: Plant Systematics and Evolution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/14/2022
Publication Date: 4/27/2022
Citation: Campos-Rocha, A., Meerow, A.W., Machado, R.M., Mayer, J.L., Da Mota, R.C., Fontana, A.P., Ribeiro, O.B., Garcia, N.B., Dutilh, J.H. 2022. Out of the mud: two new species of Hippeastrum (Amaryllidaceae) from the Doce and Jequitinhonha River basins, Brazil. Plant Systematics and Evolution. 308:22. https://doi.org/10.1007/s00606-022-01805-3.
DOI: https://doi.org/10.1007/s00606-022-01805-3

Interpretive Summary: Brazil is the largest center of distribution of the genus Hippeastrum (Amaryllidaceae family), which has given many horticulturally important amaryllis hybrid plants. However, most of the Amaryllidaceae species in the wild are restricted to localized habitats. They are threatened by over-collection and ecological destruction due to various anthropogenic pressures. It is imperative that these threatened wild amaryllis species be identified and taxonomically described before they are irreversibly lost from their native habitat. In this study, we successfully described two Hippeastrum species, (viz., H. carassense and H. velloziflorum) that are endemic in nature and faced the worst ecological disaster due to the collapse of an iron ore dam dumping millions of tons of tailing into the Doce River in southeast Brazil. We provide illustrations and identification keys to the above Hippeastrum species known to occur only in this restricted geological region near the Doce River in southeast Brazil. Such discovery of new Hippeastrum species can contribute to novel breeding opportunities with unique phenotypic characteristics for the ornamental flowering industry.

Technical Abstract: In 2015, Brazil faced the worst environmental disaster in its history, when the collapse of an iron ore dam dumped millions of tons of tailings into the Doce River. In this paper, we describe two Hippeastrum species native to localities directly involved in the tragedy. The dam was located in the foothills of Serra do Caraca, a mountain range in the state of Minas Gerais, from where we describe the endemic H. carassense; H. velloziflorum was first found on an inselberg located on the banks of the Doce River, in the neighboring state of Espirito Santo. Comments on their distribution, ecology, and phenology are provided, as well as comparisons with the most similar taxa. The conservation status of the two new species is preliminarily assessed, and both are considered threatened with extinction. We also compared their leaf anatomy and micromorphology with related species of Amaryllidaceae. Based on nrDNA ITS, we infer the phylogenetic position of H. velloziflorum, a taxon with several unique morphological characters for Hippeastrum, as the first branch in subgenus Hippeastrum. The placement of H. velloziflorum in Hippeastrum is also supported by anatomical and cytological data. The somatic chromosome number was 2n = 22, and the karyotype formula was 2n = 8m + 12sm + 2st chromosome pairs. An identification key to the species of Hippeastrum occurring in the Doce and Jequitinhonha River basins is presented.