DNA but not always morphology help to recognise monophyletic genera within ‘Cercyon’ terrestrial water scavenger beetles: a case study of Asiacyon gen. nov. (Coleoptera: Hydrophilidae)
Zuqi Mai
A B , Liyang Wang C , Sergey K. Ryndevich D , Martin Fikáček E F * , Emmanuel Arriaga-Varela G H and Fenglong Jia A *
A
B
C
D
E
F
G
H
Abstract
DNA-based studies have revealed that the terrestrial water scavenger beetle genus Cercyon Leach, 1817 (Coleoptera: Hydrophilidae: Sphaeridiinae: Megasternini) is polyphyletic, grouping similarly looking but unrelated species that were not assigned to other genera due to the absence of unusual morphological characters. In this study, we analyse the morphology, DNA data and species diversity of one of the Asian clades of ‘Cercyon’ to test whether a natural, phylogeny-based generic classification can be established. We add DNA data (five nuclear and three mitochondrial fragments) for additional species and specimens of the clade to test its monophyly and reveal phylogenetic relationships among species. We perform a detailed morphological study of all species, including SEM micrographs, to reveal synapomorphies of the DNA-based clades. We demonstrate that the lineage, described here as Asiacyon Mai, Jia, Ryndevich & Fikáček, gen. nov., is strongly supported by DNA data, has limited distribution (eastern Asia), and its species share similar biology (inhabiting fresh or decaying plant tissues), though it can be only diagnosed by a combination of plesiomorphic characters. A detailed treatment is provided for the Chinese species, including species diagnoses, illustrations of habitus and male genitalia, (re)descriptions and a key to species. A total of 14 Chinese species are recognised, of which 11 are described as new: Asiacyon pax sp. nov. (Guangdong, Hong Kong, Hunan), A. pseudincretus sp. nov. (Anhui, Jiangxi, Taiwan, Zhejiang), A. vicincretus sp. nov. (Guangdong, Guangxi), A. zhengyucheni sp. nov. (Yunnan), A. huilanae sp. nov. (Yunnan), A. cornipenis sp. nov. (Yunnan), A. belousovi sp. nov. (Yunnan), A. liangchengi sp. nov. (Yunnan), A. paraequalis sp. nov. (Yunnan), A. pengzhongi sp. nov. (Hunan) and A. xiuzhenae sp. nov. (Hainan, Yunnan). Three Chinese species previously classified in Cercyon are transferred to Asiacyon: A. incretus (d’Orchymont, 1941), comb. nov., A. primoricus (Ryndevich & Prokin, 2017), comb. nov. (newly recorded from China) and A. indicus (d’Orchymont, 1926), comb. nov. (newly recorded from China and Laos). Additionally, seven Asian species previously classified in Cercyon are transferred to Asiacyon based on their external morphology, but not studied in detail: A. aequalis (Sharp, 1884), comb. nov., A. conjiciens (Walker, 1858), comb. nov., A. dilutus (Régimbart, 1903), comb. nov., A. placidus (Sharp, 1884), comb. nov., A. pseudodilutus (Satô, 1979), comb. nov., A. retius (Ryndevich & Prokin, 2017), comb. nov., and A. rubicundus (Sharp, 1884), comb. nov. In total, the genus now comprises 21 named species and several undescribed species from India, Myanmar and Indonesia.
ZooBank: urn:lsid:zoobank.org:pub:E3C949A0-34E4-46EF-BA6A-2CD048D583B2
Keywords: Asia, China, Hydrophilidae, identification key, Megasternini, molecular systematics, morphology, natural classification, new combination, new genus, new species, Sphaeridiinae.
References
Arriaga-Varela E, Seidel M, Deler-Hernández A, Viktor S, Fikáček M (2017) A review of the Cercyon Leach (Coleoptera, Hydrophilidae, Sphaeridiinae) of the Greater Antilles. ZooKeys 681, 39-93.
| Crossref | Google Scholar | PubMed |
Arriaga-Varela E, Seidel M, Fikáček M (2018a) A new genus of coprophagous water scavenger beetle from Africa (Coleoptera, Hydrophilidae, Sphaeridiinae, Megasternini) with a discussion on the Cercyon subgenus Acycreon. African Invertebrates 59(1), 1-23.
| Crossref | Google Scholar |
Arriaga-Varela E, Wong SY, Kirejtshuk A, Fikáček M (2018b) Review of the flower-inhabiting water scavenger beetle genus Cycreon (Coleoptera, Hydrophilidae), with descriptions of new species and comments on its biology. Deutsche Entomologische Zeitschrift 65, 99-115.
| Crossref | Google Scholar |
Arriaga-Varela E, Sýkora V, Fikáček M (2021) Molecular phylogeny of Megasternini terrestrial water scavenger beetles (Hydrophilidae) reveals repeated continental interchange during Paleocene-Eocene thermal maximum. Systematic Entomology 46, 570-591.
| Crossref | Google Scholar |
Bloom DD, Fikáček M, Short AEZ (2014) Clade age and diversification rate variation explain disparity in species richness among water scavenger beetle (Hydrophilidae) lineages. PLoS ONE 9, e98430.
| Crossref | Google Scholar | PubMed |
d’Orchymont A (1926) Contribution à l'étude des Hydrophilides VI. Bulletin et Annales de la Société Enlomologique de Belgique 66, 201-248 [In French].
| Google Scholar |
d’Orchymont A (1941) Palpicornia (Coleoptera). Notes diverses et espècsummarizales I. Bulletin du Musée Roya’ d’Histoire Naturelle de Belgique 17(1), 1-23 [In French].
| Google Scholar |
d’Orchymont A (1942) Palpicornia (Coleoptera). Notes diverses et espècsummarizales. III. Bulletin du Musée Royal d’Histoire Naturelle de Belgique 18(26), 1-20 [In French].
| Google Scholar |
Fikáček M (2009) Occurrence of introduced species of the genus Cercyon (Coleoptera: Hydrophilidae) in the Neotropical region. Revista de la Sociedad Entomológica Argentina 68(3–4), 351-357.
| Google Scholar |
Hansen M (1991) The hydrophiloid beetles. Phylogeny, classificationand a revision of the genera (Coleoptera, Hydrophiloidea). Biologiske Skrifter 40, 1-368.
| Google Scholar |
Hebauer F (2003) Review of the Malgassic Cercyon, with description of new species and a new genus (Coleoptera: Hydrophilidae). Acta Coleopterologica 19(2), 5-26.
| Google Scholar |
Jia FL, Liang ZL, Ryndevich SK, Fikáček M (2019) Two new species and additional faunistic records of Cercyon Leach, 1817 from China (Coleoptera: Hydrophilidae). Zootaxa 4565(4), 501-514.
| Crossref | Google Scholar | PubMed |
Jia FL, Liang ZL, Fikáček M (2020) A review of Himalcercyon stat. nov., with description of a new species from the Chinese Himalaya and an updated key to Asian genera of Megasternini (Coleoptera, Hydrophilidae). Deutsche Entomologische Zeitschrift 67, 35-49.
| Crossref | Google Scholar |
Kearse M, Moir R, Wilson A, Stones-Havas S, Cheung M, Sturrock S, Buxton S, Cooper A, Markowitz S, Duran C, Thierer T, Ashton B, Meintjes P, Drummond A (2012) Geneious Basic: an integrated and extendable desktop software platform for the organization and analysis of sequence data. Bioinformatics 28, 1647-1649.
| Crossref | Google Scholar | PubMed |
Lanfear R, Frandsen PB, Wright AM, Senfeld T, Calcott B (2017) PartitionFinder 2: new methods for selecting partitioned models of evolution for molecular and morphological phylogenetic analyses. Molecular Biology and Evolution 34, 772-773.
| Crossref | Google Scholar | PubMed |
Miller MA, Pfeiffer W, Schwartz T (2010) Creating the CIPRES Science Gateway for inference of large phylogenetic trees. In ‘Proceedings of the Gateway Computing Environments Workshop (GCE)’, 14 November 2010, New Orleans, LA, USA. INSPEC Accession Number 11705685. (IEEE) 10.1109/GCE.2010.5676129
Nguyen L-T, Schmidt HA, von Haeseler A, Minh BQ (2015) IQ-TREE: a fast and effective stochastic algorithm for estimating maximum likelihood phylogenies. Molecular Biology and Evolution 32, 268-274.
| Crossref | Google Scholar | PubMed |
Rambaut A, Drummond AJ, Xie D, Baele G, Suchard MA (2018) Posterior summarization in Bayesian phylogenetics using Tracer 1.7. Systematic Biology 67, 901-904.
| Crossref | Google Scholar | PubMed |
Ronquist F, Teslenko M, van der Mark P, Ayres DL, Darling A, Höhna S, Larget B, Liu L, Suchard MA, Huelsenbeck JP (2012) MrBayes 3.2: efficient Bayesian phylogenetic inference and model choice across a large model space. Systematic Biology 61, 539-542.
| Crossref | Google Scholar | PubMed |
Ryndevich SK (2006) Review of species of genus Cercyon Leach, 1817 of Russia and adjacent regions. III. Subgenera Clinocercyon Orchymont, 1942 and Conocercyon Hebauer, 2003 (Coleoptera: Hydrophilidae). Zoosystematica Rossica 15(2), 315-320.
| Google Scholar |
Ryndevich SK (2008) Review of species of the genus Cercyon Leach, 1817 of Russia and adjacent regions. IV. The subgenera Paracycreon Orchymont, 1924 and Dicytocercyon Ganglbauer, 1904 (Coleoptera: Hydrophilidae). Zoosystematica Rossica 17(2), 89-97.
| Google Scholar |
Ryndevich SK, Prokin AA (2017) Two new species of Cercyon (Clinocercyon) from Russian Far East (Coleoptera:Hydrophilidae). Zootaxa 4300(1), 125-134.
| Crossref | Google Scholar |
Ryndevich SK, Jia FL, Fikáček M (2017) A review of the Asian species of the Cercyon unipunctatus group (Coleoptera: Hydrophilidae: Sphaeridiinae). Acta Entomologica Musei Nationalis Pragae 57(2), 535-576.
| Crossref | Google Scholar |
Short AEZ, Fikáček M (2011) World catalogue of the Hydrophiloidea (Coleoptera): additions and corrections II (2006–2010). Acta Entomologica Musei Nationalis Pragae 51, 83-122.
| Google Scholar |
Short AEZ, Fikáček M (2013) Molecular phylogeny, evolution, and classification of the Hydrophilidae (Coleoptera). Systematic Entomology 38, 723-752.
| Crossref | Google Scholar |
Smetana A (1978) Revision of the subfamily Sphaeridiinae of America north of Mexico (Coleoptera: Hydrophilidae). Memoirs of the Entomological Society of Canada 105, 1-292.
| Google Scholar |
Smetana A (1979) Revision of the subfamily Sphaeridiinae of America north of Mexico (Coleoptera: Hydrophilidae). Supplemen 1. Canadian Entomologist 111, 959-966.
| Google Scholar |
Smetana A (1984) Remarks on the sphaeridiine genera Pelosoma Mulsant and Deltostethus Sharp (Coleoptera: Hydrophilidae). Coleopterists Bulletin 38, 192-200.
| Google Scholar |
Smetana A (1988) Review of the family Hydrophilidae of Canada and Alaska (Coleoptera). Memoirs of the Entomological Society of Canada 142, 3-316.
| Crossref | Google Scholar |
Taekul C, Valerio A, Austin AD, Klompen H, Johnson N (2014) Molecular phylogeny of telenomine egg parasitoids (Hymenoptera: Platygastridae s.l.: Telenominae): evolution of host shifts and implications for classification. Systematic Entomology 39, 24-35.
| Crossref | Google Scholar |
Tamura K, Stecher G, Peterson D, Filipski A, Kumar S (2013) MEGA6: Molecular Evolutionary Genetics Analysis version 6.0. Molecular Biology and Evolution 30(12), 2725-2729.
| Crossref | Google Scholar |
Toussaint E, Short AEZ (2018) Transoceanic stepping stones between Cretaceous waterfalls? The enigmatic biogeography of pantropical Oocyclus cascade beetles. Molecular Phylogenetics and Evolution 127, 416-428.
| Crossref | Google Scholar | PubMed |
