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Abstract While some relationships in phylogenomic studies have remained stable since the Sanger sequencing era, many challenging nodes remain, even with genome-scale data. Incongruence or lack of resolution in the phylogenomic era is frequently attributed to inadequate data modeling and analytical issues that lead to systematic biases. However, few studies investigate the potential for random error or establish expectations for the level of resolution achievable with a given empirical data set and integrate uncertainties across methods when faced with conflicting results. Ants are the most species-rich lineage of social insects and one of the most ecologically important terrestrial animals. Consequently, ants have garnered significant research attention, including their systematics. Despite this, there has been no comprehensive genus-level phylogeny of the ants inferred using genomic data that thoroughly evaluates both signal strength and incongruence. In this study, we provide insight into and quantify uncertainty across the ant tree of life by utilizing the most taxonomically comprehensive ultraconserved elements data set of ants to date, including 277 (81%) of recognized ant genera from all 16 extant subfamilies, and representing over 98% of described species. We use simulations to establish expectations for resolution, identify branches with less-than-expected concordance, and dissect the effects of data and model selection on recalcitrant nodes. Simulations show that hundreds of loci are needed to resolve recalcitrant nodes on our genus-level ant phylogeny. This demonstrates the continued role of random error in phylogenomic studies. Our analyses provide a comprehensive picture of support and incongruence across the ant phylogeny, while offering a more nuanced depiction of uncertainty and significantly expanding generic sampling. We use a consensus approach to integrate uncertainty across different analyses and find that assumptions about root age exert substantial influence on divergence dating. Our results suggest that advancing the understanding of ant phylogeny will require not only more data but also more refined phylogenetic models. We also provide a workflow for identifying under-supported nodes in concatenation analyses, outline a pragmatic way to reconcile conflicting results in phylogenomics, and introduce a user-friendly locus selection tool for divergence dating. 

Morphometric analyses of male genitalia are routinely used to distinguish genera and species in beetles, butterflies, and flies, but are rarely used in ants, where most morphometric analyses focus on the external morphology of the worker caste. In this work, we performed linear morphometric analysis of the male genitalia to distinguish Monomorium and Syllophopsis in Madagascar. For 80 specimens, we measured 10 morphometric characters, especially on the paramere, volsella, and penisvalvae. Three datasets were made from linear measurements: mean (raw data), the ratios of characters (ratio data), and the Removal of Allometric Variance (RAV data). The following quantitative methods were applied to these datasets: hierarchical clustering (Ward’s method), unconstrained ordination methods including Principal Component Analysis (PCA), Non-Metric Multidimensional Scaling analyses (NMDS), Linear Discriminant Analysis (LDA), and Conditional Inference Trees (CITs). The results from statistical analysis show that the ratios proved to be the most effective approach for genus-level differentiation. However, the RAV method exhibited overlap between the genera. Meanwhile, the raw data facilitated more nuanced distinctions at the species level compared with the ratios and RAV approaches. The CITs revealed that the ratios of denticle length of the valviceps (SeL) to the paramere height (PaH) effectively distinguished between genera and identified key variables for species-level differentiation. Overall, this study shows that linear morphometric analysis of male genitalia is a useful data source for taxonomic delimitation. 

Abstract The classification of ants (Hymenoptera: Formicidae) has progressed in waves since the first 17 species were described by Linnaeus in the 1758 edition of Systema Naturae. Since then, over 18,000 species-rank names have accumulated for the global myrmecofauna, of which ~14,260 living and ~810 fossil species are valid. Here, we provide a synopsis of ant biodiversity and review the history and classification of the family, while highlighting the massive growth of the field in the new millennium. We observe that major transformation has occurred for ant classification due to advances in DNA sequencing technologies, model-based hypothesis testing, and imaging technologies. We therefore provide a revised and illustrated list of diagnostic character states for the higher clades of Formicidae, recognizing that vastly more work is to be done. To facilitate discussion and the systematic accumulation of evolutionary knowledge for the early evolution of the ants, we suggest an informal nomenclatural system for the higher clades of ants, based on names currently in use and a set of names that have been democratically selected by the authors. To guide future work on ant systematics, we summarize currently available databases and present perspectives on regions in need of biodiversity exploration, challenges facing the field, and the future of ant taxonomy. 

Abstract The genus Ponera includes over 60 extant species worldwide. These tiny, endogeic predator ants are predominantly distributed in the Indomalaya and Australasia regions, with a few additional Holarctic species. Herein, we explore and describe the diversity of the Malagasy Ponera fauna through an integrative taxonomic approach. We obtained our morphological species hypotheses from multivariate analyses of ten continuous morphometric characters. Species boundaries and reliability of morphological clusters were tested via confirmatory Linear Discriminant Analysis (LDA), cross-validation (LOOCV), and analyses of a mitochondrial COI gene fragment. According to the combined application of the analyses, altogether, three species are inferred in the Malagasy region, Ponera petila Wilson (1957), P. swezeyi Wheeler (1933), and P. adumbrans Csősz & Fisher sp. n. Ponera petila and P. swezeyi belong to the Indo-Australian Ponera tenuis group; the third species, P. adumbrans sp. n., is morphologically similar to the Papua New Guinean P. clavicornis Emery (1900). Furthermore, Linear Discriminant Analysis classified the type specimens of P. bableti Perrault (1993), along with a P. petila cluster with posterior p  = 1. Therefore, we propose the new junior synonymy of P. bableti with P. petila . Madagascar’s extant biodiversity is predominantly explained by colonization events from the African continent across the Mozambique channel via rafting. However, since no native Ponera species are known from the Afrotropical continent, and the closest congeners have an almost exclusively Indo-Australian distribution, the likelihood of an Indo-Australian origin of the Malagasy Ponera fauna is implied. 

The male of the myrmicine genus Erromyrma is described for the first time on the basis of two specimens of Erromyrma latinodis (Mayr, 1872) collected in northern Madagascar. We used COI barcoding to confirm the identification of the male specimens as conspecific with Erromyrma latinodis . We provide an illustrated male-based key to the four Myrmicinae tribes (Attini, Crematogastrini, Solenopsidini, Stenammini) and to the Solenopsidini genera ( Adelomyrmex , Erromyrma , Solenopsis , Syllophopsis and Monomorium ) for the Malagasy region. 

The collection of Volodymyr Opanasovych Karawajew, stored at the Schmalhausen Institute of Zoology of the National Academy of Sciences of Ukraine (SIZK, Kiev), is one of the richest ant collections of the world. It contains more than 20,000 dry mounted specimens, collected mostly in Southeast Asia and the Palaearctic, as well as in the Afrotropics, Australia, and North and South America. Among them, we found type specimens of 509 taxa, described by Karawajew and other myrmecologists. The compiled Catalogue includes data on types of 80 taxa belonging to the subfamilies Dorylinae, Amblyoponinae, Ectatomminae, Ponerinae, Proceratiinae and Pseudomyrmecinae. 

The Camponotus subgenus Myrmosaga subgen. rev. from the Malagasy region is revised based on analysis of both qualitative morphological characters and morphometric traits. The multivariate analysis used the Nest Centroid (NC)-clustering method to generate species hypotheses based on 19 continuous morphological traits of minor workers. The proposed species hypotheses were confirmed by cumulative Linear Discriminant Analysis (LDA). Morphometric ratios for the subsets of minor and major workers were used in species descriptions and redefinitions. The present study places the subgenus Myrmopytia syn. nov. in synonymy to Myrmosaga . It recognizes 38 species, of which 19 are newly described: C. aina sp. nov. , C. aro sp. nov. , C. asara sp. nov. , C. atimo sp. nov. , C. bemaheva sp. nov. , C. bozaka sp. nov. , C. daraina sp. nov. , C. harenarum sp. nov. , C. joany sp. nov. , C. karsti sp. nov. , C. kelimaso sp. nov. , C. lokobe sp. nov. , C. mahafaly sp. nov. , C. niavo sp. nov. , C. rotrae sp. nov. , C. sambiranoensis sp. nov. , C. tapia sp. nov. , C. tendryi sp. nov. , C. vano sp. nov. Eleven species are redescribed: C. aurosus Roger, C. cervicalis Roger, C. dufouri Forel, C. gibber Forel, C. hagensii Forel, C. hova Forel, C. hovahovoides Forel, C. immaculatus Forel, C. quadrimaculatus Forel, C. roeseli Forel, C. strangulatus Santschi. The following are raised to species and redescribed: C. becki Santschi stat. nov. , C. boivini Forel stat. rev. , C. cemeryi Özdikmen stat. rev. , C. mixtellus Forel stat. nov. , C. radamae Forel stat. nov. Camponotus maculatus st. fairmairei Santschi syn. nov. , is synonymized under C. boivini . The following are synonymized under C. cervicalis : Camponotus cervicalis gaullei Santschi, syn. nov. ; Camponotus perroti Forel, syn. nov. ; Camponotus perroti aeschylus Forel, syn. nov. ; Camponotus gerberti Donisthorpe, syn. nov. Camponotus dufouri imerinensis Forel, syn. nov. is a synonym of C. dufouri , Camponotus hova var. obscuratus Emery, syn. nov. is a synonym of C. hova , Camponotus quadrimaculatus opacata Emery, syn. nov. is a synonym of C. immaculatus , Camponotus maculatus st. legionarium Santschi, syn. nov. is a synonym of C. roeseli , Camponotus hova maculatoides Emery, syn. nov. is a synonym of C. strangulatus . The following are synonymized under C. quadrimaculatus : Camponotus kelleri Forel, syn. nov. , Camponotus kelleri var. invalidus Forel, syn. nov. , Camponotus quadrimaculatus sellaris Emery, syn. nov. As C. imitator Forel, C. liandia Rakotonirina & Fisher, and C. lubbocki Forel have been recently described and redescribed, only diagnoses and taxonomic discussions are provided. This revision also includes an illustrated species identification key, taxonomic discussions, images, and distribution maps for each species superimposed on the ecoregions of Madagascar. 

Global socioeconomic systems exacerbate disparities that leave a disturbing proportion of the human population malnourished, making conventional food sources such as animal livestock unsustainable at global scales. Edible insects have the potential to solve both malnourishment and the unsustainability of conventional livestock agriculture. The sustainability and accessibility of farmed, edible insects, however, depends on their feed source. Future expansion of farming rests on developing locally available and affordable insect feeds. This article presents a literature review of studies which evaluate the performance of edible crickets (Orthoptera) in response to alternative feed sources such as weeds and the byproducts of agricultural and food industries. For each insect species evaluated, we analyze measurements of feed and insect performance, feed composition, effects of diet on cricket growth and survivorship, as well as other sources of performance differences. The aim of this review is to assess the current state of alternative feed research for farmed crickets and to provide guidelines for future studies on alternative feeds.