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Sang Il Kim, Brian D. Farrell. 2015.
Phylogeny of world stag beetles (Coleoptera: Lucanidae) reveals a Gondwanan origin of Darwin's stag beetle.
Molecular Phylogenetics and Evolution, 2015, 86: 35-48.
http://dx.doi.org/10.1016/j.ympev.2015.02.015
© 2015 Elsevier Inc. All rights reserved.
Abstract
Stag beetles (family Lucanidae Latreille, 1804) are one of the earliest branching lineages of scarab beetles
that are characterized by the striking development of the male mandibles. Despite stag beetlesТ popularity
among traditional taxonomists and amateur collectors, there has been almost no study of lucanid relationships
and evolution. Entomologists, including Jeannel (1942), have long recognized resemblance between
the austral stag beetles of the tribes Chiasognathini, Colophonini, Lamprimini, Pholidotini, Rhyssonotini,
and Streptocerini, but this hypothesis of their close relationship across the continents has never been
tested. To gain further insight into lucanid phylogeny and biogeography, we reconstructed the first
molecular phylogeny of world stag beetles using DNA sequences from mitochondrial 16S rDNA, nuclear
18S and 28S rDNA, and the nuclear protein-coding (NPC) gene wingless for 93 lucanid species representing
all extant subfamilies and 24 out of the 27 tribes, together with 14 representative samples of other early
branching scarabaeoid families and two staphyliniform beetle families as outgroups. Both Bayesian inference
(BI) and maximum likelihood inference (MLI) strongly supported the monophyly of Lucanidae sensu
lato that includes Diphyllostomatidae. Within Lucanidae sensu stricto, the subfamilies Lucaninae and
Lampriminae appeared monophyletic under both methods of phylogenetic inferences; however,
Aesalinae and Syndesinae were found to be polyphyletic. A time-calibrated phylogeny based on five fossil
data estimated the origin of crown group Lucanidae as circa 160 million years ago (MYA). Divergence
between the Neotropical and Australasian groups of the Chiasognathini was estimated to be circa
47 MYA, with the South African Colophonini branching off from the ancient Chiasognathini lineage around
87 MYA. Another Gondwanan relationship was recovered between the Australasian Eucarteria and the
Neotropical Casignetus, which diverged circa 58 MYA. Lastly, as JeannelТs hypothesis predicted, divergence
within Lampriminae between the Australasian Lamprima and the Neotropical Streptocerus was estimated
to be circa 37 MYA. The split of these lineages were generally concordant with the pattern of continental
break-up of the super-continent Gondwana, and our biogeographic reconstructions based on the dispersal-
extinction-cladogenesis model (DEC) corroborate our view that the divergences in these austral
lineages were caused by vicariance events following the Gondwanan break-up. In addition, the
phylogenetic position and geographic origin of the Hawaiian genus Apterocyclus was revealed for the first
time. Overall, our results provide the framework toward studying lucanid relationships and divergence
time estimates, which allowed for more accurate biogeographic explanations and discussions on ancestral
lucanids and the evolutionary origin of the enlarged male mandibles.
Иллюстрация из статьи (Kim, Farrell, 2015). |