Genomic and Mitochondrial Data Identify Different Species Boundaries in Aposematically Polymorphic Eniclases Net-Winged Beetles (Coleoptera: Lycidae)

Abstract

Species delineation is essential for any evolutionary and biodiversity research, and recent advances in genomic sequencing have made it possible to robustly define species boundaries and detect hidden diversity. Here, we studied 14 species of aposematically colored New Guinean Eniclases (Coleoptera: Lycidae) whose conventional morphology- and single-locus mtDNA-based taxonomy has been contentious. We analyzed mitochondrial and restriction site associated DNA fragments to obtain a phylogenetic hypothesis and compared relationships recovered by the RAD analysis with species limits based on other information. The results show the presence of cryptic diversity and common mitonuclear discordance when over 30% of individuals were incorrectly assigned to species if only mitogenomic markers were considered. Nuclear data falsified the species rank of one species and identified one earlier unrecognized lineage deserving species rank. Further, our analyses demonstrate a highly variable phenotypic differentiation, with several pairs of cryptic species standing in contrast with genetically close but phenotypically highly divergent lineages. We show that morphological and mitogenomic analyses produce reliable information for taxonomy in most cases. Nevertheless, the species boundaries among closely related species should be based on all lines of evidence, including nuclear markers.

Biodiversity Inventory and Distribution of Metriorrhynchina Net-Winged Beetles (Coleoptera: Lycidae), with the Identification of Generic Ranges

“…The highest diversity of the Metriorrhynchina is known from New Guinea, especially the mountain ecosystems of the Central Cordillera, which are humid for the whole year and potentially provide favorable conditions for liquid sucking net-winged beetle larvae [ 18 , 25 ]. Since we found that New Guinea and its surrounding islands support 423 Metriorrhynchina species, it is highly probable that these represent only a fraction of the real diversity that has been shown in the recent taxonomic revisions of Diatrichalus , Falsolucidota , and Eniclases [ 39 , 45 , 71 , 75 , 101 ] and the high number of descriptions of new species from various genera by Kazantsev [ 6 , 7 , 8 , 9 ].…”

“…The poorly dispersing species are highly diversified possibly due to low gene flow between species and populations isolated by a distance and geographical barriers, such as lowlands, and mountain ranges [ 24 , 75 , 105 , 106 , 107 , 108 , 109 ]. There are only a few Metriorrhynchina genera that were able to colonize landmasses separated by the sea straits after the distance between the Australian and Asian cratons decreased in the last 20 million years [ 97 ] and biological connections were established.…”

“…Similarly, the first New Guinean Metriorrhynchina species were reported already from collections brought to Europe by the first explorers of the Pacific region [ 66 , 67 ], and the majority of currently known species were described in the period of a single decade [ 68 , 69 , 70 ]. Further alpha-taxonomic research of the New Guinea fauna was conducted by L. Bocak and M. Bocakova [ 39 , 45 ], S. V. Kazantsev [ 6 , 7 , 8 , 9 ], and several other authors [ 71 , 72 , 73 , 74 , 75 , 76 ].…”