Evolution of Spermophagus seed beetles (Coleoptera, Bruchinae, Amblycerini) indicates both synchronous and delayed colonizations of host plants.
Seed beetles are a group of specialized chrysomelid beetles, which are mostly associated with plants of the legume family (Fabaceae). In the legume-feeding species, a marked trend of phylogenetic conservatism of host use has been highlighted by several molecular phylogenetics studies. Yet, little is known about the evolutionary patterns of association of species feeding outside the legume family. Here, we investigate the evolution of host use in Spermophagus, a species-rich seed beetle genus that is specialized on two non-legume host-plant groups: morning glories (Convolvulaceae) and mallows (Malvaceae: Malvoideae). Spermophagus species are widespread in the Old World, especially in the Afrotropical, Indomalaya and Palearctic regions. In this study we rely on eight gene regions to provide the first phylogenetic framework for the genus, along with reconstructions of host use evolution, estimates of divergence times and historical biogeography analyses. Like the legume-feeding species, a marked trend toward conservatism of host use is revealed, with one clade specializing on Convolvulaceae and the other on Malvoideae. Comparisons of plants' and insects' estimates of divergence times yield a contrasted pattern: on one hand a quite congruent temporal framework was recovered for morning-glories and their seed-predators; on the other hand the diversification of Spermophagus species associated with mallows apparently lagged far behind the diversification of their hosts. We hypothesize that this delayed colonization of Malvoideae can be accounted for by the respective biogeographic histories of the two groups.
INRA, UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 Avenue du campus Agropolis, 34988 Montferrier/Lez, France. Electronic address: kergoat@supagro.inra.fr.
Gael J
GJ
Kergoat
IRD/CNRS, Laboratoire Evolution Génomes Spéciation, Avenue de la terrasse, BP1, 91198 Gif-sur-Yvette, France; Université Paris-Sud 11, 91405 Orsay, France; Unité de Recherche IRD 072, African Insect Science for Food and Health (ICIPE), PO Box 30772-00100, Nairobi, Kenya. Electronic address: bleru@icipe.org.
Bruno P
BP
Le Ru
Research Institute of Forests and Rangelands of Iran, PO Box 13185-116, Tehran, Iran. Electronic address: ebrasadeghi@gmail.com.
Seyed E
SE
Sadeghi
Institute of Biological Control, Faculty of Agriculture, Kyushu University, 812-8581 Fukuoka, Japan; Laboratory of Insect Natural Enemies, Division of Agricultural Bioresource Sciences, Department of Bioresource Sciences, Faculty of Agriculture, Kyushu University, 812-8581 Fukuoka, Japan. Electronic address: tuda@grt.kyushu-u.ac.jp.
Midori
M
Tuda
Department of Entomology, Australian Museum, 6 College Street, Sydney, NSW 2010, Australia. Electronic address: Chris.Reid@austmus.gov.au.
Chris A M
CA
Reid
Department of Zoology, Hungarian Natural History Museum, H-1088 Budapest, Baross u. 13, Hungary. Electronic address: gyorgy@zoo.nhmus.hu.
Zoltán
Z
György
INRA, UMR 1062 CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), 755 Avenue du campus Agropolis, 34988 Montferrier/Lez, France.
Gwenaëlle
G
Genson
Laboratório de Sistemática e Bioecologia de Coleoptera, Departamento de Zoologia, Universidade Federal do Paraná, Caixa Postal 19020, 81531-980 Curitiba, Paraná, Brazil. Electronic address: cibele.ribeirocosta@gmail.com.
Cibele S
CS
Ribeiro-Costa
Muséum National d'Histoire Naturelle, 45 rue Buffon, 75005 Paris, France. Electronic address: delobel.alex@aliceadsl.fr.
Alex
A
Delobel
D000818:Animals; D001517:Coleoptera / Q000145:classification / Q000235:genetics / Q000502:physiology*; D019143:Evolution, Molecular; D007887:Fabaceae / Q000469:parasitology; D058507:Host Specificity; D006790:Host-Parasite Interactions; D027741:Ipomoea / Q000469:parasitology*; D019660:Malvaceae / Q000469:parasitology*; D010802:Phylogeny; D058974:Phylogeography; D012639:Seeds / Q000469:parasitology*; D017422:Sequence Analysis, DNA; D013997:Time Factors
Bruchinae; Convolvulaceae; Historical biogeography; Host-plant associations; Malvoideae; Spermophagus