A Phylogenetic Analysis of Loasaceae Subfamily Loasoideae Based on Plastid DNA Sequences

Abstract

Questions of tribal and generic circumscriptions and relationships in Loasaceae subfamily Loasoideae are addressed in phylogenetic analyses that apply four plastid regions in parsimony and maximum likelihood analyses. As circumscribed in the influential monograph of Urban and Gilg, Loaseae are paraphyletic to the sister clades Klaprothieae (Klaprothia, Plakothira, and Xylopodia) and Kissenieae (Kissenia). This problem centers on the paraphyly of Huidobria: Huidobria chilensis is sister to Klaprothieae þ Kissenieae, and Huidobria fruticosa is sister to all other Loasoideae. Parametric bootstrapping finds topologies that force the monophyly of Huidobria to be significantly different from the optimal topologies in which the genus is paraphyletic; however, Templeton and Shimodaira-Hasegawa tests did not distinguish between these phylogenetic alternatives. We recognize a strongly supported Loaseae sensu stricto (s.str.) as a clade consisting of Nasa, Aosa, Chichicaste, Presliophytum, Blumenbachia, Cajophora, Loasa sect. Loasa, and Scyphanthus. In Loaseae s.str., the monophyly of each of the following has strong support: (1) Nasa, (2) Aosa þ Chichicaste, (3) Presliophytum þ Loasa malesherbioides, and (4) a higher Loaseae clade that consists of Blumenbachia, Cajophora, Scyphanthus, and the Loasa complex (¼sect. Loasa, excluding L. malesherbioides). Blumenbachia, Cajophora (including exemplars from sections Bialatae and Bicallosae), and Scyphanthus are independently monophyletic, and clades of the Loasa complex are mixed among them. The paraphyletic Loasa complex includes the following clades: (1) ser. Pinnatae, (2) ser. Acaules þ Volubile, (3) ser. Macrospermae, placed as the sister of Blumenbachia, and (4) ser. Acanthifolia þ Floribundae þ Deserticolae, which includes the type for Loasa and is the group we recommend as the basis for a revised circumscription of Loasa.

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

“…Approximately 70% of the currently recognized species in SAL were included in this study, and the results confirm the conclusions obtained in previous molecular studies (Weigend , 2004b;Hufford & al., 2005), while providing increased support and resolution (Fig. 1).…”

“…Outgroups were selected based on the phylogenetic studies of Weigend & al. (2004b) and Hufford & al. (2005) as well as on the familial and ordinal classification outlined by APG IV (2016).…”

“…The group comprises over 80 species in the genera Caiophora, Blumenbachia, Scyphanthus Sweet and Loasa (Weigend & al., 2004b, 2008Ackermann, 2011) and-as the name implies-has its centre of diversity in the southern Andes, but representatives extend from Cotopaxi (central Ecuador) and Rio de Janeiro (southeastern Brazil), to Magallanes (Chile) and Santa Cruz (Argentina). SAL share several synapomorphies (Weigend & al., 2004b) and represent a monophyletic group based on molecular data (Moody & al., 2001;Hufford & al., 2003Hufford & al., , 2005Weigend & al., 2004b;Strelin & al., 2017). Loasa, originally the largest genus (Urban & Gilg, 1900), had already lost most of its species to the segregate genera (Weigend, 1997(Weigend, , 2004; see above), but molecular data indicated that the redefined Loasa s.str.…”

Consideraciones sobre la sistemática de las familias y los géneros de plantas vasculares endémicos de Chile

“…Por otro lado, cabe señalar que la presencia del género en Juan Fernández se debería a una introducción desde el continente (Marticorena 1990, Danton et al 2006. LOASACEAE Huidobria Gay A pesar de ser reconocido como género endémico por Moreira-Muñoz (2011) y el Catálogo, Huidobria aparece como parafilético en varios análisis filogenéticos con ambas especies en una politomía en la base de la subfamilia Loasoideae (Moody et al 2001, Hufford et al 2003, Hufford et al 2005. Sin embargo, Hufford et al (2005) señalan que esto requiere pruebas y datos filogenéticos adicionales.…”

“…En la mayoría de los casos se presenta inlcuido en Loasa, junto con Caiophora y Blumenbachia (Moody et al 2001, Hufford et al 2003, Hufford et al 2005, lo que podría provocar una futura reclasificación. Respecto de su distribución geográfica, Scyphanthus ha sido considerado como endémico de Chile (Marticorena 1990, Zuloaga et al 2008, Moreira-Muñoz 2011.…”