Corresponding author: Michele Rossini (
Academic editor: A. Frolov
In this study, we test and corroborate the phylogenetic position of
Rossini M, Montreuil O, Grebennikov V, Tarasov S (2021) Genome sequencing reveals extraordinary cephalic horns in the Madagascan dung beetle genus
The dung beetle tribe
Thus, considering the exclusive phenotype of
Voucher specimens and type material analyzed throughout the study are deposited in the following institutes:
The external morphology, along with the anatomy of the male and female genitalia of a total of 39
Morphological study was performed under a Leica S9D stereomicroscope. Habitus photographs were taken with a Canon EOS 5D camera and a Canon MP-E 65mm, f/2.8, 1–5× macro lens, using the Cognisys Stackshot automated system; male genitalia were photographed with a Nikon SMZ25 stereomicroscope coupled with a DS-Ri2 camera. Zerene Stacker (v. 1.04 Build T2020-05-22-1330) software and NIS-Elements-BR (Nikon Imaging Software Basic Research) were used to process and combine multiple photographs. Images were enhanced and arranged in plates in Adobe Photoshop and Illustrator CC 2015.
Genomic DNA was extracted from an ethanol-preserved female of
The read quality was checked with FastQC (
The ingroup consisted of 44 operational taxonomic units (
Gene fragments were individually aligned using MAFFT (
The combined phylogenetic analyses of the fragments of 19 mitochondrial and nuclear genes support the monophyly of the genus
Molecular phylogenies and morphological synapomorphies of the
Interestingly, our combined analysis and that of
According to
These putative synapomorphies are not found in
Interestingly,
1 | Pronotal punctation strong and coarse; elytral interstriae granulose; major male with long and widely curved clypeal horns (Fig. |
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– | Pronotal punctation very fine; elytral interstriae without granules; male without horns |
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2 | Clypeal margin of male and female with two acute teeth at middle; male with a small transversal clypeal carina (Fig. |
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– | Clypeal margin of male and female with three blunt to acute teeth at middle; male without clypeal carina |
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3 | Frontoclypeal region with a distinct hump, postoccipital margin with a pointed tubercle in the middle (Fig. |
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– | Frontoclypeal region and postoccipital margin simple to slightly swollen (Fig. |
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Of
Of
This species is distributed from the northernmost region of Madagascar to the central-western coast. It is known from the Diana, Melaky, Boeny, and Menabe regions.
The examination of the holotype of
This species is known from the central-western coast of Madagascar (Boeny and Menabe regions).
Only known from south-western Madagascar (Atsimo-Andrefana region).
Madagascar: “Mt. d’Ambre.
Within the endemic Madagascar genus
Posteromedial pronotal region with punctation rugulose-lacunose and coarse, central and medial region without punctures, punctation more spaced in the anterior region. Several punctures associated with short and stout setae. Pronotal tegument shiny and smooth on anterior half, posterior half finely microsculptured and especially in the middle.
Propleuron weakly excavated at the bottom of the pronotal anterior angles; propleuron with two carinae, the internal carina thinner and straight, external one stronger and widely sinuate.
Episternum very narrow; mesosternal surface covered by coarse and dense punctures associated with short and stout setae, anterior region of mesosternum with a wide and smooth bead, triangularly pointed backward at middle; metasternum wide and steeply elevated with respect to the mesosternum in its superior region, surface smooth, with fine punctures on the disc and coarse punctures near the mesocoxae.
Sternites ventrally visible, anterior margin with a double row of coarse and shallow punctures not perfectly aligned, three rows of punctures on the lateral most region of each sternite.
Pygidium flattened, completely margined, pygidial surface finely microreticulated and with scattered, shallow punctures.
First segment of mesotarsi with four spine-like teeth in the external margin, two to three yellow setae inserted between each tooth.
Females differ from males by the clypeal margin with three teeth distinctly reflexed upward, the lateral teeth obtuse, while the central one more acuminated, posterior margin of the lateral teeth with short setae; head surface covered by coarse and shallow punctures even on the clypeus where the punctation is shallower; pronotum not depressed medially; protibia without internoapical tooth; last abdominal sternite narrower at middle.
We are thankful to Gunilla Ståhls-Mäkelä for DNA extraction of
This study was supported by the Pentti Tuomikoski Fund and the Academy of Finland Grant (#331631), awarded to ST.
DNA sequence alignment of the material examined in our study
Authors: Michele Rossini, Olivier Montreuil, Vasily Grebennikov, Sergei Tarasov
molecular data
Copyright notice: This dataset is made available under the Open Database License (