Phylogeny and biogeography of the tribe Liabeae (Compositae subfamily Cichorioideae)

Abstract

AbstractThe tribe Liabeae (Compositae) contains ca. 175 species distributed in 18 genera and its members occupy a variety of habitats in the Andes of South America as well as in Mexico, Central America, and the West Indies. The tribe is recognizable by a combination of morphological characters. DNA sequence data from the nuclear ribosomal ITS region and three chloroplast regions (trnL–F, 3’ end of ndhF, matK; a total of more than 5 kb of sequence data) were used to infer a phylogeny. The data were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference. The results support the monophyly of the tribe and show a consistent placement for all genera except Cacosmia. Four well–supported clades are recovered in the remainder of the tribe, all recognized as subtribes. Liabineae (Ferreyranthus, Dillandia, Oligactis, Sampera, Liabum) are the sister group of the rest of the tribe. Sinclairineae (Sinclairiopsis and Sinclairia with segregates Liabellum and Megaliabum) are the sister group of Munnoziinae (Chrysactinium nested inside Munnozia s.l.) plus Paranepheliinae (Stephenbeckia,Microliabum, Pseudonoseris, Paranephelius, Chionopappus, Philoglossa, Erato). Cacosmia is placed as the sister group of either all the rest of the tribe or of subtribe Liabineae; morphologically its characters are either autapomorphic or plesiomorphic. Bishopanthus could not be confidently placed in any of the subtribes; it is only known from scraps of the type and a molecular study is not possible. The phylogeny slightly alters previous assumptions about the biogeography and it seems that Liabeae originated in the central and northern Andes and spread north and south with several independent introductions into Mexico and Central America and one into the Caribbean. With the exception of the Liabeae (Andes) and Moquineae (Brazil), all of the tribes in the subfamily Cichorioideae are either restricted to or have their basal grade in Africa.