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Background: Next-generation sequencing technology can now be used to sequence historical specimens from natural history collections, an approach referred to as museomics. The museomics allows obtaining molecular data from old museum-preserved specimens, a resource of biomolecules largely underexploited despite the fact that these specimens are often unique samples of nomenclatural types that can be crucial for resolving scientific questions. Despite recent technical progress, cricket mitogenomes are still scarce in the databases, with only a handful of new ones generated each year from freshly collected material., Methods: In this study, we used the genome skimming method to sequence and assemble three new complete mitogenomes representing two tribes of the cricket subfamily Eneopterinae: two were obtained from old, historical type material of Xenogryllus lamottei (68 years old) and X. maniema (80 years old), the third one from a freshly collected specimen of Nisitrus vittatus . We compared their genome organization and base composition, and reconstructed the molecular phylogeny of the family Gryllidae., Results: Our study not only confirmed that the genome skimming method used by next generation sequencing allows us to efficiently obtain the whole mitogenome from dry-pinned historical specimens, but we also confirmed how promising it is for large-scale comparative studies of mitogenomes using resources from natural history collections. Used in a phylogenetic context the new mitogenomes attest that the mitogenomic data contain valuable information and also strongly support phylogenetic relationships at multiple time scales., Competing Interests: Tony Robillard is an Academic Editor for PeerJ., (©2024 Dong et al.)

For a long time, New Caledonia was considered a continental island, a fragment of Gondwana harbouring old clades that originated by vicariance and so were thought to be locally ancient. Recent molecular phylogenetic studies dating diversification and geological data indicating important events of submergence during the Paleocene and Eocene (until 37 Ma) brought evidence to dismiss this old hypothesis. In spite of this, some authors still insist on the idea of a local permanence of a Gondwanan biota, justifying this assumption through a complex scenario of survival by hopping to and from nearby and now-vanished islands. Based on a comprehensive review of the literature, we found 40 studies dating regional clades of diverse organisms and we used them to test the hypothesis that New Caledonian and inclusive Pacific island clades are older than 37 Ma. The results of this meta-analysis provide strong evidence for refuting the hypothesis of a Gondwanan refuge with a biota that originated by vicariance. Only a few inclusive Pacific clades (6 out of 40) were older than the oldest existing island. We suggest that these clades could have extinct members either on vanished islands or nearby continents, emphasizing the role of dispersal and extinction in shaping the present-day biota.

Relict species have always beguiled evolutionary biologists and biogeographers, who often view them as fascinating 'living fossils' or remnants of old times. Consequently, they are believed to provide interesting and important information on a vanished past and are used to understand the evolution of clades and biotas. The information that relicts provide can, however, be misleading and overemphasised when it is not remembered that they belong to groups or biotas that are mostly extinct. For example, relict species imply regional extinctions and, for this reason, they cannot simultaneously provide evidence of local biota permanence. Here we consider carefully misconceptions about relict species and highlight more clearly their evolutionary and biogeographical significance., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

We reconstruct a comprehensively sampled molecular phylogeny for the second most species‐rich tribe of the ladybird beetle family Coccinellidae, the charismatic Coccinellini. We analysed a dataset consisting of five nuclear and three mitochondrial gene fragments from 150 taxa to provide a detailed phylogeny and estimates of historical divergence times using Bayesian relaxed clocks and primary fossil calibrations and an assessment of the evolution of feeding habits. The results of phylogenetic analyses provide strong support for the monophyly of the tribe Coccinellini, highlight the existence of four major clades and most sampled Coccinellini genera (30 out of 34) were recovered monophyletic. Our dating analyses suggest an Early Cretaceous origin for Coccinellidae at ca. 140 millions years ago (Ma) and a Late Cretaceous origin for the tribe Coccinellini at ca. 83.8 Ma. Ancestral character state estimation of feeding habits highlights a high level of phylogenetic niche conservatism on aphids and indicates that the most common recent ancestor of Coccinellini likely also fed on aphids. Our reconstruction of feeding habits and assessment of the aphid fossil record suggests that the diversification of Coccinellini paralleled that of Aphididae, although with substantial variation in host‐breadth and the tendency for a few specialized lineages towards non‐aphid feeding. [ABSTRACT FROM AUTHOR]

The monophyletic Morpho sulkowskyi butterfly group, endemic of Andean cloud forests, was studied to test the respective contributions of Mio-Pliocene intense uplift period and Pleistocene glacial cycles on Andean biodiversity. We sampled nine taxa covering the whole geographical range of the group. Two mitochondrial and two nuclear genes were analysed using a Bayesian method. We established a dated phylogeny of the group using a relaxed clock method and a wide-outgroup approach. To discriminate between two hypotheses, we used a biogeographical probabilistic method. Results suggest that the ancestor of the M. sulkowskyi group originated during the Middle-Late Miocene uplift of the Eastern Cordillera in northern Peru. Biogeographical inference suggests that the M. sulkowskyi and Morpho lympharis clades diverged in the northern Peruvian Andes. The subsequent divergences, from the Late Miocene to the Late Pliocene, should have resulted from a dispersal towards the Northern Andes ( M. sulkowskyi clade), after the closure of the West Andean Portal separating the Central and Northern Andes, and a southwards dispersal along the Peruvian and Bolivian Eastern Cordilleras ( M. lympharis clade). Only a few divergences occurred at the very end of the Pliocene or during the Pleistocene, a period when the more recent uplifts interfered with Pleistocene glacial cycles. [ABSTRACT FROM AUTHOR]

Nattier, R., Robillard, T., Amedegnato, C., Couloux, A., Cruaud, C. & Desutter-Grandcolas, L. (2011) Evolution of acoustic communication in the Gomphocerinae (Orthoptera: Caelifera: Acrididae). - Zoologica Scripta, 40, 479-497. We used a phylogenetic analysis to study the communication behaviour in the Gomphocerinae (Insecta, Orthoptera, Acrididae), which are characterised by their stridulatory apparatus and a diversified acoustic repertoire. Song-emitting behaviour, together with the general description, temporal dimension and amplitude of signals were used to describe the calling song of 34 species, resulting in a matrix of 39 acoustic characters. A phylogeny using 59 gomphocerine species and two outgroups was built based on four mitochondrial markers and the acoustic characters. Based on acoustic character optimisations, ancestral calling song was reconstructed and the evolution of calling song is discussed, with a comparison to courtship behaviours. Our results show a dynamic process of calling song evolution and underline a balance between calling and courtship diversity leading to two mating strategies corresponding to two major clades in the phylogeny. [ABSTRACT FROM AUTHOR]

An increasing variety of extrinsic traits are used in comparative studies aimed at testing evolutionary hypotheses. After briefly reviewing the relevant literature, it appears that three different problems are implied by this trend. Some extrinsic traits are only surrogates for phenotypic traits, and should be redefined to better fit the requisites for phylogenetic analysis, such as selective regimes and extinction risks. Some others are already adequately defined and cannot be made less extrinsic, such as taxon age, geographical distribution, associates (parasites, symbionts, etc.), and bioclimatic modelled niches. Because they are not heritable, they should not be analysed by optimization onto a tree, but are better considered in sister-group comparisons or within a reconciliation procedure, as already done for areas of biogeography. © The Willi Hennig Society 2010. [ABSTRACT FROM AUTHOR]