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Beetles, despite their remarkable biodiversity and a long history of research, remain lacking in reference genomes annotated with structural variations in loci of adaptive significance. We sequenced and assembled high‐quality chromosome‐level genomes of four Hercules beetles which exhibit divergence in male horn size and shape and body colouration. The four Hercules beetle genomes were assembled to 11 pseudo‐chromosomes, where the three genomes assembled using Nanopore data (Dynastes grantii, D. hyllus and D. tityus) were mapped to the genome assembled using PacBio + Hi‐C data (D. maya). We demonstrated a striking similarity in genome structure among the four species. This conservative genome structure may be attributed to our use of the D. maya assembly as the reference; however, it is worth noting that such a conservative genome structure is a recurring phenomenon among scarab beetles. We further identified homologues of nine and three candidate‐gene families that may be associated with the evolution of horn structure and body colouration respectively. Structural variations in Scr and Ebony2 were detected and discussed for their putative impacts on generating morphological diversity in beetles. We also reconstructed the demographic histories of the four Hercules beetles using heterozygosity information from the diploid genomes. We found that the demographic histories of the beetles closely recapitulated historical changes in suitable forest habitats driven by climate shifts. [ABSTRACT FROM AUTHOR]

Forest soil and leaf litter support diverse arthropod mesofauna for which diversity dynamics is challenging to study due to the high number of species and specimens, small body size and limited taxonomic knowledge.Immature stages (larvae) are even harder to identify than adults, as their morphology is largely unknown. Therefore, larvae are often ignored, even though they may form a substantial proportion of specimens collected, are less mobile than adults and their exclusion may provide an incomplete diversity profile.Here, we use Oxford Nanopore DNA barcoding to investigate whether the inclusion of larvae provides a more complete taxonomic, phylogenetic and functional diversity profiles in leaf litter beetles (Coleoptera) from a subtropical forest in Taiwan.Our results indicate that larvae represent up to 38% of beetle specimens per sample, but most of them belong to 2–3 common species. Larvae of most beetle species are rarely collected repeatedly or in multiple specimens, possibly due to special habitat requirements or high seasonality.Taxonomic, phylogenetic and incidence‐based functional diversity measures were not affected by the exclusion of larvae in the Staphylinidae dataset but were strongly biased in all‐beetle dataset, especially when only common or abundant species were considered. Taxonomic beta diversity was not affected by the omission of larvae.Our results indicate that immature stages may be omitted in ecological studies of arthropods in case both adults and larvae co‐occur in the same habitat, and the sites are sampled repeatedly. Caution is needed (1) in groups in which larvae and adults do not inhabit the same environment or strongly differ in biology, (2) when rare species are omitted or (3) when functional diversity is calculated from abundance data. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2006.09.023 Byline: I.-Min Tso, Jen-Pan Huang, Chen-Pan Liao Abstract: Many studies have shown that colour signals are important in spider-insect interactions. The bright body coloration of certain orb-weaving spiders seems to serve as a visual lure to diurnal prey. However, no studies have examined whether this coloration affects spiders' nocturnal hunting. Some nocturnal lepidopteran pollinators use colour vision to locate their food resources, so orb-weaving spiders' bright coloration may also be attractive to visually oriented nocturnal insects. To assess the role of body coloration of the orchid spider, Leucauge magnifica, in luring nocturnal prey, we investigated whether: (1) these spiders actively hunt during the night; (2) nocturnal prey comprise a significant proportion of total prey intake; and (3) altering body colour signals significantly affect the nocturnal prey capture rate. Round-the-clock monitoring of L. magnifica activity patterns showed that they hunt more actively at night. Owing to the presence of relatively large moths in their diet at night, L. magnifica consumed higher prey biomass during nocturnal hunting, although this was not statistically significant owing to large variability. Painting over the spiders' yellow ventrum stripes significantly reduced their moth capture rate. These results show that certain orb-weaving spiders with bright body coloration attract nocturnal prey, and they obtain larger prey from nocturnal hunting. Author Affiliation: (a) Center for Tropical Ecology and Biodiversity, Taiwan (a ) Department of Life Science, Tunghai University, Taiwan Article History: Received 18 January 2006; Revised 10 March 2006; Accepted 13 September 2006 Article Note: (miscellaneous) MS. number: 8807R

A starlike water-soluble fullerene derivative, hexa(suffonbutyl)fullerene ([C.sub.60][([[C[H.sub.2]).sub.4]S[O.sub.3.sup.-].sub.6]; HSBF), consisting of a [C.sub.60] cage covalently bonded with six negatively charged sulfonate arms, was synthesized and used to selectively precipitate positively charged surfactants, amino acids, peptides, and proteins. The affinity of HSBF to the analytes depends on the charge, structure, and hydrophobic characteristics of the analytes. The ion pair precipitate was easily removed from the solution by centrifugation. After washing, the precipitate was redissolved in the solvent or buffer solution and the analyte was characterized by laser desorption ionization-time-of-flight mass spectrometry (LD-TOF). HSBF shows strong optical absorbance in the UV range, so no additional organic matrix was required to conduct LD-TOF analysis of small analytes. For the solution that contained five quaternary amines differing only in alkyl chain length, HSBF exhibits the highest affinity to the amine with the longest alkyl chain. Only the arginine signal was detected from the solution that contained 14 amino acids. The peptides with arginine as the end groups interacted most strongly with HSBF and could be selectively precipitated from a solution of a mixture of five peptides. The signals associated with a trace amount of charged peptides derived from the digestion of proteins by trypsin were greatly enhanced after concentration with HSBF. Among eight proteins in the sample solution, insulin had the strongest affinity to the HSBF and exhibited the strongest signal on the matrix-assisted laser desorption/ionization mass spectrum.

The genealogical divergence index (gdi) was developed to aid in molecular species delimitation under the multispecies coalescent model, which has been shown to delimit genetic structures but not necessarily species. Although previous studies have used meta-analyses to show that gdi could be informative for distinguishing taxonomically good species, the biological and evolutionary implications of divergences showing different gdi values have yet to be studied. I showed that an increase in gdi value was correlated with later stages of divergence further along a speciation continuum in an Amazonian Hercules beetle system. Specifically, a gdi value of 0.7 or higher was associated with diverge between biological species that can coexist in geographic proximity while maintaining their evolutionary independence. Divergences between allopatric species that were conventionally given subspecific status, such as geographic taxa that may or may not be morphologically divergent, had gdi values that fell within the species delimitation ambiguous zone (0.2 < gdi < 0.7). However, the results could be drastically affected by the sampling design, i.e. the choice of different geographic populations and the lumping of distinct genetic groups when running the analyses. Different gdi values may prove to be biologically and evolutionarily informative should additional speciation continua from different empirical systems be investigated, and the results obtained may help with objectively delimiting species in the era of integrative taxonomy. [ABSTRACT FROM AUTHOR]

Consistent and objective species delimitation is crucial to biodiversity studies, but challenges remain when conflicting taxonomic decisions have been made because different data sets and analytical methods were used to delineate species. In the rhinoceros beetle, Xylotrupes siamensis , the use of different morphological characters has resulted in taxonomic disagreement between studies. We used three molecular loci (mitochondrial CO1 and nuclear ITS2 and H3) to investigate the genetic divergence between populations exhibiting different male horn phenotypes. We also applied an approximate Bayesian computation approach to test alternative historical hypotheses that might explain the present genetic diversity among geographical populations. Furthermore, we used species distribution models to estimate the temporal variation in the geographical distribution of suitable habitats. The results show that the two phenotypic taxa within X. siamensis are not genetically structured and that their genetic structure can be explained using isolation by geographical distance. The emergence of the two phenotypic taxa might have been associated with historical isolation in separate refugia. However, spatial expansion and genetic interchange between populations might have gradually eroded the spatial genetic structure. We demonstrate that understanding the historical processes responsible for phenotypic divergence and genetic diversity among current populations could help with making evolutionarily coherent taxonomic decisions. [ABSTRACT FROM AUTHOR]