Phylogenetic relationships and generic re‐arrangements in “South Andean Loasas” (Loasaceae)

Abstract

Loasaceae, a mostly American group, is one of the largest families of Cornales. In spite of considerable progress over the last 20 years, the relationships of some clades remain controversial, especially in the “South Andean Loasas” (SAL—Blumenbachia, Caiophora, Loasa, Scyphanthus). The present study addresses the phylogenetic relationships in SAL employing four plastid markers (rps16, trnL‐trnF, trnS‐trnG, matK) and ITS and aims at resolving the systematics and evolution of the group. Sequences obtained from a total of 59 SAL species (ca. 70% of the total, representing all lineages in the group) and 25 outgroup taxa were analysed using maximum likelihood and Bayesian inference approaches. ML best and BI strict consensus trees showed no significant differences in their topologies. Our results confirm that two species of Loasa ser. Malesherbioideae are not part of the SAL clade, but should be included in Presliophytum, a result which is here formalized. Blumenbachia (including sect. Angulatae and sect. Gripidea) is confirmed as a monophylum with high support. Loasa has to be redefined and restricted to a clade including only ser. Deserticolae, ser. Floribundae, ser. Loasa and ser. Macrospermae. Scyphanthus and Caiophora both are each monophyla and sister groups, but with two clades of Loasa as successive sister groups: (((Caiophora+Scyphanthus)+Loasa ser. Pinnatae)+(L. ser. Volubiles+L. ser. Acaules)) in a very well‐supported clade. Accordingly, Caiophora, Loasa ser. Pinnatae, L. ser. Volubiles, L. ser. Acaules and Scyphanthus could be included into a single genus, with Scyphanthus taking priority over Caiophora, creating a fairly heterogenous genus of ca. 52 species and requiring 50 new names. Alternatively, the clades Loasa ser. Pinnatae and L. ser. Volubiles + ser. Acaules can be removed into new segregate genera, which is here argued for and which requires the creation of only 16 new names. The new genus names and some of the new combinations are here formalized.

A case of behavioural diversification in male floral function – the evolution of thigmonastic pollen presentation

“…Molecular studies have largely confirmed earlier systematic re-arrangements based on morphology (e.g. 53 ), and the phylogeny of the group can be considered as well-resolved 54 – 56 . In spite of its relatively moderate number of species, the family is morphologically highly diversified (Fig.…”

“…The PCR amplification and sequencing protocols follow Acuña et al . 56 . Sequences were assembled in Geneious v. 8.0.1 84 using the default De Novo assemble settings.…”

A new striking and critically endangered species of Nasa (Loasaceae, Cornales) from North Peru

“…We analysed sequences from four plastid regions: trn L– trn F, mat K, the trn S– trn G intergenic spacers and the rps 16 intron. These have proved to be informative to infer the phylogenetic relationships in Loasoideae (Weigend et al 2004; Hufford et al 2005; Weigend and Gottschling 2006; Acuña et al 2017). Sequences were newly generated for this study or for previously published research by our working group (Acuña et al 2017, 2018; Henning et al 2018).…”

New Insights Into Grausa: Reinstatement, Distribution and Affinities of Loasa Acaulis (Loasaceae, Loasoideae)

“…Our sampling for the molecular study included 81 species (ca. 25%) of Loasaceae, plus six asterids which broadly mirrored sampling from Acuña et al (2017). All currently recognized genera and most major infrageneric clades of Loasaceae subfamily Loasoideae were included.…”

“…Volubiles and ser. Acaules from Loasa s.s. into the new genus Grausa Weigend & R.H. Acuña (Acuña et al, 2017) Acuña], but also the acaulescent, high-Andean G. lateritia. As Loasa acaulis was considered a synonym of L. lateritia it was implicitly assumed that it was also part of Grausa, however this has never been tested using phylogenetic (molecular or otherwise) evidence.…”