Presentation given at the 2014 Annual Meeting of the Entomological Society of America.

1. © Carlos De Soto Molinari
Guanyang Zhang, Usmaan Barashat & Nico Franz
Arizona State University
taxonbytes.org somanyinsects.org @GYZhang2
Entomological Society of America Annual Meeting, Portland, Oregon, Nov 19, 2014

2. Curculionidae: Entiminae: Eustylini
(A) E. agrestis (Boheman); (B) E. consobrinus (Marshall); (C) E. hieroglyphicus Chevrolat(D) E. impressus
(Fabricius); (E) E. nicaraguensis Bovie; (F) E. quadrivittatus (Olivier)(G) E. quinquedecimpunctatus (Olivier);
(H) E. roseipes (Chevrolat); (I) E. sulcicrus Champion(J) E. triangulifer Champion; (K) E. verecundus
(Chevrolat); (L) E. vittatus (Linnaeus)

3. Exophthalmus Schoenherr, 1823
 85 described species; Caribbean [~45] and Neotropical mainland [~40]
Chauliopleurus Champion, 1911 [4 spp.]
Compsoricus Franz, 2012 [3]
Decasticha Champion, 1911 [5]
Diaprepes Schoenherr, 1823 [19]
Pachnaeus Schoenherr, 1826 [7]
ca. 131 species
Rhinospathe Chevrolat, 1878 [2]
Tropirhinus Schoenherr, 1823 [4]
Tetrabothynus Labram & Imhoff, 1852 [2]
Based on Franz (2012) Biol. J. Linn. Soc. (A
narrower definition is used here)
Species counts from O’brien & Wibmer (1982)

4. High endemism in Caribbean islands (e.g., 89% in Cuba) (Peck, 2005)
In Exophthalmus continental diversity is mainly concentrated
in Central America (including Southern Mexico) (~35 spp.);
low diversity in South America (8 spp.)
http://www.freeworldmaps.net/centralamerica/map.html
Species of Exophthalmus
genus complex are distributed
from Southern Mexico,
Caribbean to Northern South
America.

5. Can vicariance model sensu Rosen (1975) explain
continent-island relationship?
~65 Ma ~40 Ma ~40 Ma to present
Figure by Nearns & Branham, adapted from Rosen (1975),
http://kellymillerlab.com/pdf/Nearns&Branham_2008.pdf
Caribbean fauna date back to
~65 Ma (late Cretaceous/early
Cenozoic)
Area relationship

6. Are Caribbean islands strictly a ‘colonization sink’, or
could they also be a source for continental diversity?
Bellemain, E., & Ricklefs, R. E. (2008). Are islands the end of the
colonization road? Trends in Ecology & Evolution, 23(8), 461–468.
doi:10.1016/j.tree.2008.05.001

7. Are Caribbean islands strictly a ‘colonization sink’, or
could they also be a source for continental diversity?
 Unidirectional colonization from continent to islands has
been the dominant model
 Reverse colonization from Caribbean to Neotropical
mainland documented in Anolis, birds (bananaquits,
Myiarchus, parrots), turtles, and frogs (Eleutherodactylus)

8. Are Caribbean islands strictly a ‘colonization sink’, or
could they also be a source for continental diversity?
 In Anolis island to continent colonization and radiation
generated >150 species in mainland
Caribbean islands Neotropical
mainland

9. Are Caribbean islands strictly a ‘colonization sink’, or
could they also be a source for continental diversity?
 What patterns would weevils show?
?
?

10. Over-water dispersal model by Hedges et al.
Primarily based on vertebrates

11. Island-island vicariance of the GAARLandia, late Oligocene
land span (Iturralde-Vinent & McPhee, 1999)
35 – 32 Ma

12. Island-island vicariance of the GAARLandia, late Oligocene
land span (Iturralde-Vinent & McPhee, 1999)
27 – 25 Ma

13. Island-island vicariance of the GAARLandia, late Oligocene
land span (Iturralde-Vinent & McPhee, 1999)
16 – 14 Ma

14. Predictions of the models
Over-water
dispersal
Island-island
vicariance
Times of
divergences
Scattered Clustered
Ancestral ranges Narrow or
widespread
Widespread
Relationships
among island
species
Sister relationship
between any
islands
(Cuba, (Hispaniola,
Puerto Rico))

15. Biogeographic reconstruction with BioGeoBears
 Extends DEC model (Dispersal, Extinction, Cladogenesis)
to include founder-event dispersal (DEC + j )
 Founder-event dispersal leads to cladogenesis
DEC + j A DEC
AB
(founder-event)

16. Taxonomic sampling
 ~65 spp. from the Exophthalmus genus complex
(50% of described diversity)
 25 outgroups

17. • Caribbean: Cuba,
Hispaniola, Puerto
Rico, Jamaica, Lesser
Antilles (Dominica, St.
Lucia, Virgin Islands)
(50 spp.)
• Central America:
Panama, Costa Rica,
Nicaragua (15 spp.)
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America

18. Molecular phylogeny and dating
 6 genes: COI, COII, 12s (Mitochondrial); 28s, Ef-1α, Arginine
kinase (nuclear); 4747 bp (aligned)
 Dated phylogeny obtained using BEAST 1.8, with three fossil
calibration points based on Dominican ambers (16 Ma;
Miocene)
Biogeographic reconstruction with BioGeoBears
(Matzke, 2014)

20. DEC DEC + j (founder-event)
LnL = -167 LnL = -117
• DEC + j fit better to
data
• Ancestral ranges
resolved to single
areas
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America

21. Caribbean species are paraphyletic rendered by
Central American species
Central American clade comprises a single radiation
Caribbean Central American

22. Colonization of Central America from the Caribbean
occurred once in early Miocene (~18 Ma) through
founder event dispersal
Caribbean Central American
18.8-18.1 Ma

23. Dispersal mechanism may involve rafting on flotsams
(floating vegetation), produced by hurricanes/thunderstorms
and propelled by prevailing water currents
A floating island of vegetation (ca. 600 square meters) © Pervaze Sheikh
in Amazon river, carrying a cattle egret (Bubulcus ibis) (1997 in Brazil)

24. Southeast to northwest surface-water currents in Caribbean
since Oligocene could have facilitated oceanic over-water
dispersal
Water currents directions (Hedges, 2006)

25. Reconstruction of ancestral ranges
recovered episodic dispersal events via
founder speciation
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America
Ancestral areas were
reconstructed with BioGeoBears
& mapped on dated phylogeny

26. 20 10 0
Miocene
Plio
Pl
ei
• Island species are not
monophyletic
Cuba
Ma

27. 20 10 0
Miocene
Plio
Pl
ei
Hispaniola
Ma
• Island species are not
monophyletic

28. 20 10 0
Miocene
Plio
Pl
ei
• Island species are not
monophyletic
Jamaica

29. 20 10 0
Miocene
Plio
Pl
ei
Puerto Rico
Ma
• Island species are not
monophyletic

30. 20 10 0
Miocene
Plio
Pl
ei
Lesser Antilles
Ma
• Island species are not
monophyletic

31. 20 10 0
Miocene
Plio
Pl
ei
Central America
Ma
• Para- or polyphyly of island
species contrasts to single origin
of mainland clade

32. 20 10 0
Miocene
Plio
Pl
ei
• Relationships within & between
island species suggest complex
biogeographic history
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America
Ma

33. 20 10 0
Miocene
Plio
Pl
ei
Ma
• Cuba was the ancestral
range of entire clade in late
Oligocene
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America
24.3 Ma

34. 20 10 0
Miocene
Plio
Pl
ei
Ma
• Founder-event dispersal – one
daughter lineage colonizes a
new range and another retains
the ancestral range
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America
A founder
dispersal
example
Founder-event
dispersal

35. 20 10 0
Miocene
Plio
Pl
ei
Ma
• 14 founder-event dispersals
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America
inferred
• Nearly all prior to 13 Ma (11/14)
• Several clades diversified
within- island
Founder-event
dispersal

36. L P H J U C
L - 1
P 1 - 1 1 1 1
H -
J 1 - 1
U 3 3 -
C -
Cuba and Puerto Rico were
major sources of colonists
(11 emigrations out of these
islands)
No emigration out of
Hispaniola
Sink
Source
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America

37. Cuba and Puerto Rico were
major sources of colonists
(11 emigrations out of these
islands)
No emigration out of
Hispaniola
Emigration
Immigration
Cuba
Hispaniola
Jamaica
Puerto Rico
Lesser Antilles
Central America

38. Central America was colonized from the Caribbean
in early Miocene through over-water dispersal
Episodic founder-event dispersals best explain
current distribution in Caribbean
Model with founder-event dispersal (DEC + j)
outperformed DEC

39. Include additional samples from Mesoamerica
(Southern Mexico and Guatemala) and Northern
South America
Increase outgroup sampling to test origin of
Caribbean species
Explore/devise methods to model changing
geography

40. NSF DEB-1155984 (to N. Franz)
USDA (Agreement No. 58-1275-1-335; to N. Franz)
Dr. Nick Matzke (BioGeoBear analyses)
Anyi Mazo Vargas (preliminary DNA data)
Dr. Robert Anderson (specimens; Candiana Museum of Nature)
Dr. Steve Davis (AMNU), Dr. Conrad Labandeira (USNM)
(loan of fossils)
Albert Deler Hernandez, Franklyn Cala Riquelme (field
assistance in Cuba)
Franz Lab: Sal Anzaldo, Andrew Jansen, Andrew
Johnston, Dr. Sangmi Lee (www.Taxonbytes.org)