AbstractThe subfamily Murininae is renowned for its inherent taxonomic challenges associated with sampling difficulties and morphological similarities. At present, three genera are acknowledged within the subfamily; however, their phylogenetic interrelations and systematic classification remain debated. In this study, the separation of Harpiola at the genus level was robustly supported by our phylogenomic analyses based on the mitochondrial genome, coding sequences (CDSs) and ultraconserved elements (UCEs) from 12 individuals covering all three genera of Murininae. Notably, a distinctive mito‐nuclear discordance emerged, with the nuclear genealogy ((Harpiocephalus, Harpiola), Murina) contrasting with the mitochondrial genealogy (Harpiocephalus, (Harpiola, Murina)). The integration of these findings with inferences of demographic history reveals that dramatic environmental changes during the Pleistocene glacial and inter‐glacial cycles have shaped the current distribution of Murininae. Moreover, the detection of extensive gene flow between ancient lineages of Harpiola and Murina suggests that an ancestral ‘ghost’ Murina lineage may have contributed its mitochondrial DNA, along with a limited portion of nuclear DNA, to Harpiola in a bygone hybridization zone. In addition to molecular analyses, we employed traditional and geometric morphometric analyses of skulls to differentiate the three genera. Harpiocephalus is readily distinguishable, but Harpiola and certain species of Murina exhibit overlapping characteristics both morphometrically and geometrically which may be the outcome of ancient introgression events. This finding highlights the importance of fine‐scale morphological distinctions within the latter genera, which may be the outcome of ancient introgression events.

AbstractThe study of adaptive radiations has shed light on our current understanding of evolution. However, previous studies examining the mode in which species diversified, how diversification rates varied, and how ecological specialisation affected these processes have found few different results across different taxa and geographic and ecological systems, showing how complex this process is. To gain a more complete picture of how species evolve, additional model systems that encompass alternative ecological requirements are needed. Here, we present the results of a study aimed at unravelling the diversification mode and evolutionary drivers of the spider genus Dysdera, the red devil spiders, endemic to the Canary Islands. These species exhibit remarkable phenotypic variability in their mouthparts, which has been related to different levels of specialisation in the predation of isopods. We explored patterns of lineage diversification and assessed the role of trophic specialisation as a driver of species diversification. Additionally, we used climatic variables, occurrence data and morphological information to unravel the underlying mode of speciation by means of joint species distribution models and age‐range correlation methods. Our results reveal that red devil spiders underwent an early burst of diversification, followed by a slowdown of diversification rates, which is a hallmark of adaptive radiation. We also found evidence that the trophic morphology shaped diversification, with specialist species exhibiting higher rates of diversification. Finally, our analyses suggest that speciation occurred mostly in allopatry, with subsequent secondary sympatry following range expansion.

AbstractEriophyoid mites (Acari: Eriophyoidea) are among the smallest terrestrial arthropods possessing simplified morphological characters, which challenges the traditional morphology‐based species delimitation. The Diptilomiopus spp. exhibit further morphological degeneration (e.g., lack of genus on both legs and some opisthosoma setae). Especially, they possess high similarity in the reticulate prodorsal shield patterns, leading to cryptic species complex and hampering our understanding of species diversity. In this study, we implemented an integrated approach, including genetic distance analysis, phylogenetic analysis, population genetic structure construction, introgression test, and morphometric analysis, to delimitate the Diptilomiopus ligustri complex. We obtained 52 mitochondrial COI gene sequences and 19 whole‐genome sequences across 18 sample sites of this complex. All samples were collected from Ligustrum plants in China, which may cover their main distribution ranges. Our results demonstrate that the D. ligustri complex consists of at least four distinct species (i.e., D. ligustri, D. cf. ligustri sp1., D. cf. ligustri sp2., and D. cf. ligustri sp3.), which are genetically divergent but do not differ morphologically, assessed by principal component analysis of 27 morphological characteristics. No significant gene flow was observed among this complex. Divergence time estimates further showed that most Diptilomiopus species diverged in a short time interval at the Paleogene–Neogene boundary, indicating a rapid radiation. Our results highlight the integrated approaches in eriophyoid mite species complex delimitation.

AbstractStripes and bands are common colour patterns in snakes. Some species are known to exhibit colour polymorphism and that includes expressing it in the bands and stripes. Bridal snake, Dryocalamus is a medium‐sized arboreal snake in South to Southeast Asia and most species of the genus are banded, but including two striped species. In Borneo, banded D. subannulatus and striped D. tristrigatus occur sympatrically and the two species are similar morphologically except for their colour patterns. We hypothesized the two species in Borneo exhibit a significant colour dimorphism of one species and conducted morphological and genetical analysis to test the hypothesis. Morphological examinations revealed that D. subannulatus and D. tristrigatus are not distinguishable in Borneo by scalation. Mitochondrial phylogenetic analysis and nuclear SNP analysis showed D. subannulatus and D. tristrigatus from Borneo formed clades or clusters by region not by species. Dryocalamus subannulatus and D. tristrigatus in Borneo are morphologically and genetically indistinguishable and Bornean D. subannulatus should be treated as a colour morph of D. tristrigatus. This is a rare example of sympatrically distinct banded/striped dimorphism in snakes. Relative abundance of banded/striped morph of the genus is probably different depending on region, and any ecological factor may contribute to it.

AbstractMalachiinae (Coleoptera: Malachiidae), commonly known as true soft‐winged flower beetles, are widely distributed across the globe except New Zealand. It is the largest subfamily of Cleroidea (over 3000 species) and is currently divided into seven tribes, among which the relationships are hard to assess due to their bizarre morphological modifications in males. Although a few molecular phylogenetics were attempted, they were all constructed on basis of four or five short nucleotide fragments, which may not contain enough phylogenetic information, thereby resulting in unclear relationships. To investigate the phylogenetic relationships among the tribes within Malachiinae, low‐coverage whole genomes of 26 species from the superfamily Cleroidea were sequenced and analysed, including 22 species of Malachiinae. The mitochondrial genomes (mitogenomes), nuclear genes (18S, 28S rRNA) and universal single‐copy orthologs (USCOs) were obtained as molecular markers from low‐coverage sequencing data. A total of 24 complete or nearly complete mitochondrial genomes of Malachiidae species were annotated and analysed. Further combined the newly sequenced data and those available in the public database, four different data matrices were analysed by different methods to reconstruct the phylogeny of Malachiinae. The results indicated that these phylogenetic analyses produced consistent topologies, and the phylogenetic relationships within Malachiinae were recovered as (Illopini + (Troglopini + (Colotini + Apalochrini))) + (Ebaeini + (Attalini + Malachiini)).

AbstractThe phylogenetic position of the tardigrade species Grevenius annulatus was clarified using specimens from North‐West Russia. Molecular phylogenetic analysis revealed close affinity of this species with the family Isohypsibiidae. At the same time, its isolated position within this clade, supported by a set of unique morphological and biological characters, prompted the distinguishing of a new genus Cucumibius gen. nov. A new genus Chilibius gen. nov. was also established for Isohypsibius sculptus. We provide a detailed description of the ultrastructure of C. annulatus comb. nov. body cuticle. The newly discovered presence of a complex cuticle of the ‘heterotardigrade type’ in the superfamily Isohypsibioidea is discussed.

AbstractAs defining various taxonomic ranks, especially at and within a specific level, can often be difficult, we used an evolutionarily young group of Central Asian beetles, the genus Anoplistes, to examine the limits between species, subspecies and ecotype. The molecular data (COI genetic distance, haplotype network and species delimitation) and detailed morphology (using SEM) of taxa assigned to the rank of species, subspecies and ecotype were used to verify their taxonomic status and attempt to more precisely establish the boundaries between these concepts. The minimum threshold for the COI genetic distance between species was found to be approximately 3%, while at the threshold of 4%–5% the morphology left no doubt as to the species distinctiveness. The threshold of approximately 2% was accepted as adequate for a subspecies rank, whereas intraspecific variability among individuals of the same subspecies (including its ecotypes) ranged from 0% to 2%. A newly presented colour/elytral pattern form, possibly another ecotype of A. halodendri distributed in western Mongolia, exemplifies adaptation to different environmental conditions via ecological speciation. Our results provide support that ecotypes can form phylogenetically distinct clades. Based on the results of the haplotype network, it can be tentatively concluded that the sand ecotype was the incipient form from which further ecotypes and subspecies developed.