Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread

Khaya (Meliaceae) is a widespread genus of trees distributed from the tropical forests of Africa to Madagascar and the Comoros. Khaya species are very close morphologically and some contain considerable phenotypic and ecological diversity, raising the question of their delimitation: this is the case...

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Autores principales: Bouka, Gaël U.D., Doumenge, Charles, Ekué, Marius, Daïnou, Kasso, Florence, Jacques, Degen, Bernd, Loumeto, Jean Joël, McKey, Doyl, Hardy, Olivier J.
Formato: Journal Article
Lenguaje:Inglés
Publicado: Wiley 2022
Materias:
Acceso en línea:https://hdl.handle.net/10568/119493
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author Bouka, Gaël U.D.
Doumenge, Charles
Ekué, Marius
Daïnou, Kasso
Florence, Jacques
Degen, Bernd
Loumeto, Jean Joël
McKey, Doyl
Hardy, Olivier J.
author_browse Bouka, Gaël U.D.
Daïnou, Kasso
Degen, Bernd
Doumenge, Charles
Ekué, Marius
Florence, Jacques
Hardy, Olivier J.
Loumeto, Jean Joël
McKey, Doyl
author_facet Bouka, Gaël U.D.
Doumenge, Charles
Ekué, Marius
Daïnou, Kasso
Florence, Jacques
Degen, Bernd
Loumeto, Jean Joël
McKey, Doyl
Hardy, Olivier J.
author_sort Bouka, Gaël U.D.
collection Repository of Agricultural Research Outputs (CGSpace)
description Khaya (Meliaceae) is a widespread genus of trees distributed from the tropical forests of Africa to Madagascar and the Comoros. Khaya species are very close morphologically and some contain considerable phenotypic and ecological diversity, raising the question of their delimitation: this is the case of Khaya anthotheca s.l. (sensu lato, including K. nyasica), which is often lumped with K. grandifoliola and K. ivorensis. We tested species delimitation within K. anthotheca by combining population‐genetic and morphological data. First, a visual inspection of over a thousand specimens suggested the existence of five morphogroups. Second, after genotyping 498 samples at 71 nuclear SNPs, Bayesian clustering analyses (STRUCTURE) first identified five genetic clusters (K1–K5), while further analyses subdivided K5 into two clusters. The six genetic clusters obtained are distributed in parapatry or allopatry from West Africa to East Africa, except for cluster K4, which is in sympatry with K3 in Central Africa. The partitioning of genetic clusters is also largely congruent with the morphogroups identified. The morphological differentiation of these clusters was confirmed by statistical analyses of 27 leaf characters. The clear‐cut genetic differentiation between clusters, with few admixed genotypes even in contact zones, argues for the recognition of distinct species following the biological species concept. Our analyses highlight that the current taxonomic treatment of Khaya underestimates by one‐half the total number of species. We identify two new species, circumscribe K. anthotheca and support the rehabilitation at the rank of species of three taxa considered to be synonyms of K. anthotheca (K. agboensis, K. euryphylla, K. nyasica). These results illustrate the strength of combining population‐genetic and morphological data to delineate an African rainforest tree species complex.
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spelling CGSpace1194932025-12-08T09:54:28Z Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread Bouka, Gaël U.D. Doumenge, Charles Ekué, Marius Daïnou, Kasso Florence, Jacques Degen, Bernd Loumeto, Jean Joël McKey, Doyl Hardy, Olivier J. plant morphology species diversity genetic variation genetic markers rainforests morfología vegetal diversidad de especies variación genética Khaya (Meliaceae) is a widespread genus of trees distributed from the tropical forests of Africa to Madagascar and the Comoros. Khaya species are very close morphologically and some contain considerable phenotypic and ecological diversity, raising the question of their delimitation: this is the case of Khaya anthotheca s.l. (sensu lato, including K. nyasica), which is often lumped with K. grandifoliola and K. ivorensis. We tested species delimitation within K. anthotheca by combining population‐genetic and morphological data. First, a visual inspection of over a thousand specimens suggested the existence of five morphogroups. Second, after genotyping 498 samples at 71 nuclear SNPs, Bayesian clustering analyses (STRUCTURE) first identified five genetic clusters (K1–K5), while further analyses subdivided K5 into two clusters. The six genetic clusters obtained are distributed in parapatry or allopatry from West Africa to East Africa, except for cluster K4, which is in sympatry with K3 in Central Africa. The partitioning of genetic clusters is also largely congruent with the morphogroups identified. The morphological differentiation of these clusters was confirmed by statistical analyses of 27 leaf characters. The clear‐cut genetic differentiation between clusters, with few admixed genotypes even in contact zones, argues for the recognition of distinct species following the biological species concept. Our analyses highlight that the current taxonomic treatment of Khaya underestimates by one‐half the total number of species. We identify two new species, circumscribe K. anthotheca and support the rehabilitation at the rank of species of three taxa considered to be synonyms of K. anthotheca (K. agboensis, K. euryphylla, K. nyasica). These results illustrate the strength of combining population‐genetic and morphological data to delineate an African rainforest tree species complex. 2022-08 2022-05-10T07:56:37Z 2022-05-10T07:56:37Z Journal Article https://hdl.handle.net/10568/119493 en Open Access application/pdf Wiley Bouka, G.U.D.; Doumenge, C.; Ekué, M.R.M.; Daïnou, K.; Florence, J.; Degen, B.; Loumeto, J.J.; McKey, D.; Hardy, O.J. (2022) Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread. Taxon, Online first paper (02 May 2022). 19 p. ISSN: 0040-0262
spellingShingle plant morphology
species diversity
genetic variation
genetic markers
rainforests
morfología vegetal
diversidad de especies
variación genética
Bouka, Gaël U.D.
Doumenge, Charles
Ekué, Marius
Daïnou, Kasso
Florence, Jacques
Degen, Bernd
Loumeto, Jean Joël
McKey, Doyl
Hardy, Olivier J.
Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread
title Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread
title_full Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread
title_fullStr Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread
title_full_unstemmed Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread
title_short Khaya revisited: Genetic markers and morphological analysis reveal six species in the widespread
title_sort khaya revisited genetic markers and morphological analysis reveal six species in the widespread
topic plant morphology
species diversity
genetic variation
genetic markers
rainforests
morfología vegetal
diversidad de especies
variación genética
url https://hdl.handle.net/10568/119493
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