Molecular systematics of the Catesbaeeae‐Chiococceae complex (Rubiaceae): flower and fruit evolution and biogeographic implications

Abstract

The classification of the Catesbaeeae and Chiococceae tribes, along with that of the entire Rubiaceae, has long been debated. The Catesbaeeae-Chiococceae complex (CCC) includes approximately 28 genera and 190 species primarily concentrated in the Greater Antilles (nearly 70% of the species), Central and South America, and in the western Pacific (three genera). Previous molecular studies, with broad sampling of the Rubiaceae, have shown the CCC to be a monophyletic group. The present study is a more detailed examination of the generic relationships within the CCC using two data sets, the nuclear ribosomal ITS regions and the trnL-F chloroplast intron and spacer. Maximum parsimony analyses lend further support to the previous hypotheses that the CCC is monophyletic and sister to Strumpfia maritima. However, within the complex several genera do not form monophyletic groups. Previous studies of the Rubiaceae suggest that the ancestral fruit type in the CCC is a multiseeded capsule. Indehiscent, fleshy fruits appear to have evolved three to four times within this lineage. Changes in floral morphologies within the complex tend to correspond to cladogenesis among and within genera. Finally, molecular analyses suggest one or possibly two long-distance dispersals from the Americas to the western Pacific.Key words: biogeography; Caribbean; Catesbaeeae; Chiococceae; flower evolution; fruit evolution; islands; ITS; Neotropics; Pacific; Rubiaceae; systematics; trnL-F.The Rubiaceae is one of the largest and most diverse families of flowering plants, with approximately 650 genera and 13 000 species (Delprete, 2004), mostly of pantropical distribution. Historically fruit and seed characters have been used to infer the classification of the family and in several cases to define subfamilies (de Candolle, 1830; Hooker, 1873;Schumann, 1891). The subfamilial and tribal classification went through several minor modifications until Bremekamp (1966), using many additional characters, divided the family into eight The authors thank Lynn Raulerson and Agnus Rinehart (University of Guam), and Ritidian National Wildlife Refuge, Guam, David Lorence (National Tropical Botanical Garden, Lawai, Hawaii), George Proctor (Institute of Jamaica, Natural History Division, Kingston, Jamaica), Andreas Oberli (Hope Gardens, Kingston, Jamaica), Luke Lee and Kevin Boswell (Forestry Department of Jamaica), Teodoro Clase (Jardín Botánico Nacional, Santo Domingo, Dominican Republic), Tanguay Jaffré and Jean-Christphe Pintaud (IRD, Noumea, New Caledonia), David Orr (Waimea Arboretum, Hawaii), and Barry Hammel (Missouri Botanical Garden) for field assistance and advice; Kobinah Abdul-Salim (NYBG) for statistical advice; Claes Persson (Gö-teborg University) and anonymous reviewers for their helpful suggestions, the curators of NOU and NY herbaria, and the National Tropical Botanical Garden, Waimea Arboretum and the Hope Gardens for permission to sample herbarium and/or living collections.

New World Origins of Southwest Pacific Gesneriaceae: Multiple Movements Across and Within the South Pacific

“…However, subtropical Coronanthereae might have been unsuited for the cool climate and extreme seasonality of Antarctica, which finally became inhospitable to woody plants ;15 Ma (Hill and Scriven 1995). The findings in numerous molecular studies now support the hypothesis that current biotic patterns in the southern Pacific are influenced by dispersal (Swenson and Bremer 1997;Hurr et al 1999;Wagstaff et al 2000Wagstaff et al , 2002Mummenhoff et al 2001;Gemmill et al 2002;Winkworth et al 2002b;Howarth et al 2003;Nepokroeff et al 2003;Smissen et al 2003;Berry et al 2004;Clement et al 2004;Mummenhoff 2004;Albach et al 2005;Bartish et al 2005;Cronk et al 2005;Motley et al 2005;Meudt and Simpson 2006;Clark et al 2008Clark et al , 2009Pfeil and Crisp 2008;Smith et al 2008;Tay et al 2010). The inference of dispersal has been most obvious for species on oceanic islands of recent origin but less so for those on continental islands.…”

“…However, such a pattern is not unique to Gesneriaceae. Motley et al (2005) postulated one or two long-distance dispersal events from the Caribbean to the western Pacific among Bikkia and its relatives (Rubiaceae), with no evidence of island hopping.…”

Systematics, taxonomy and floristics of Brazilian Rubiaceae: an overview about the current status and future challenges

“…2003;Delprete & Cortés-B. 2004;Dessein 2003;Lantz 2003;Motley et al 2005;Persson 2000a,b;Piesschaert et al 2000;Razafimandimbison & Bremer 2001, 2002Rova et al 2002;Stoffelen et al 1996), with the intent of clarifying the subfamilial, tribal and generic delimitation in the Rubiaceae. Following these studies, a family classification for a general overview on the systematic significance of pollen in the Rubiaceae was published by Dessein et al (2005), where significant correlations with tribal delimitations were detected.…”

“…(Motley et al 2005), with the main center of diversity in the Greater Antilles, several genera in Central and South America, and a few genera in the islands of the South Pacific. In Brazil are present the following genera: Chiococca P. Browne, Coutarea Aubl., Erithalis P. Browne, Exostema (Pers.)…”

Phylogenetics, Conservation, and Historical Biogeography of the West Indian Members of the Adelieae (Euphorbiaceae)

“…), a genus endemic to Cuba and Hispaniola, and the Jamaican endemic Portlandia P. Browne (7 spp.) are sister taxa (Motley & al., 2005 (Nordenstam, 2006).…”