Phylogenetic analysis of Migadopinae Chaudoir, 1861, based on morphological characters analyzed using maximum parsimony and Bayesian inference, recognizes the tribal adelphotaxaAquilicini Moret, 2005 and Migadopini. Amarotypini Erwin, 1985 (type genus Amarotypus Bates, 1872) is newly synonymized with Migadopini, as its taxonomic recognition renders Migadopini paraphyletic. Phylogenetic relationships within Migadopinae establish the Andean tropicomontane Aquilex Moret, 1989-type genus of the monogeneric Aquilicini-as sister group to the circum-Antarctic Migadopini. The earliest-diverging member taxa of Migadopini are distributed across southern South America and the subantarctic Falkland Islands. Subsequent divergence implicates Australia, New Zealand, and the Campbell Plateau. Internodes of the taxon-area cladogram are optimized using RASP (Reconstruct Ancestral State in Phylogenies), with nodal optimizations interpretable by both vicariance or dispersal. Campbell Plateau taxa are ambiguously derived from an ancestral node optimized to either South America, Australia, or the Campbell Plateau itself, a result most consistent with fragmentation of these Gondwanan terranes. Only the origin of the Tasmanian Migadopiella Baehr-taxonomically placed within a paraphyletic assemblage comprising the New Zealand genera Amarotypus, Amaroxenus Larochelle & Larivi & egrave;re, and Amarophilus Larochelle & Larivi & egrave;re-is interpreted unambiguously as dispersal based, in this instance via east to west trans-Tasman dispersal. Winged flight by migadopine carabid beetles, previously hypothesized as a vehicle for dispersal between Australia and SouthAmerica, is dismissed based on restriction of macropterous taxa to two disparate and highly subordinate taxa; one comprising the Australian tropicomontane Dendromigadops Baehr and its temperate rainforest-occupying sister genus Decogmus Sloane, and the second, Antarctonomus complanatus of Valdivian and Magellanic Nothofagus forest in Chile and Argentina. Relevant fossil evidence supporting austral relationships of Migadopinae is briefly reviewed, including the mid-Cretaceous occurrence of Migadopinae in Kachin Burmese Amber, and the Miocene-aged fossil carabid beetle, Antarctotrechus balli Ashworth and Erwin (Trechini), described from the trans-Antarctic Mountains. The former supports a Cretaceous origin for Migadopinae consistent with Austral vicariance, the latter augurs the discovery of biogeographically homologous Antarctic fossil representatives that could corroborate an Austral vicariance hypothesis for the migadopine radiation.

Incagonum jcbradleyi Liebherr and Will, new species is described from La Oroya, Junín Department, Peru. The type series was collected during J. C. Bradley's visit to Peru, May–August 1920. The species is taxonomically placed among Peruvian members of the genus and proposed as adelphotaxon to Incagonum hiekei Allegro, Giachino, and Moret. Whereas I. hiekei is characterized by brachypterous flight wings, the metathoracic wings of I. jcbradleyi are vestigial, i.e., not extended beyond the hind margin of the metanotum. Incagonum jcbradleyi exhibits diagnostic features of the genus, including the absence of subapical lateral setae on metatarsomere 4 and the presence of a digitiform basal process on the spermatheca. The latter structure is also part of the spermathecal assemblages of various Glyptolenus Bates species, supporting sister-group status of Incagonum Liebherr and Glyptolenus, both Neotropical genera. Discovery of I. jcbradleyi in Junín narrows the distributional gap between the northern set of Peruvian Incagonum species and Incagonum mateui (Moret) and Incagonum inca (Moret)—restricted to Cuzco and Puno departments—at the same time suggesting that substantial biodiversity of Peruvian Incagonum remains to be discovered in the intervening departments of Huancavelica, Ayacucho, and Apurímac.

A new species of the carabid beetle genus Bembidion Latreille is described from the Central Valley, Los Angeles Basin, and surrounding areas of California. Bembidionbrownorumsp. nov. is a distinctive species, a relatively large member of the subgenus Notaphus Dejean, and within Notaphus a member of the B.obtusangulum LeConte species group. It has faint spots on the elytra and a large, convex, rounded prothorax. Of the 22 specimens from 11 localities, all but one were collected more than 55 years ago. Although the collection of the holotype in 2021 at UV light suggest the species is still extant, the lack of other recent specimens suggests the species may have a more restricted distribution than in the past, and its populations may be in decline.

The fossil record suggests some insect species have a marked longevity. The oldest fossils purported to represent extant insect species are from the Oligocene and Eocene. One of the most cited fossils is the extant tiger beetle Tetracha carolina (Coleoptera: Cicindelidae) that was identified over a century ago by Walther Horn in Eocene Baltic amber. We examined this and compared it to the previously described cincindelid Baltic amber fossil Palaeoiresina cassolai using X-ray microscopy and 3D imaging techniques. We conclude that Horn's fossil tiger beetle specimen is conspecific with the Eocene P. cassolai and is a member of an extinct stem group lineage of Cicindelidae. Based on a review of all the tiger beetle fossils described from Cretaceous and Paleogene deposits, we found that the assignment of these fossil species to extant lineages is not supported. There are currently no synapomorphies known from fossils that can provide evidence for Cretaceous Manticorni or Megacephalini nor is there evidence for Eocene Iresina. We provide evidence that rejects the idea of a recent beetle species persisting since the Eocene period, which is crucial for using the currently known fossil Cicindelidae species to calibrate divergence dating of beetle phylogenies.

Abstract. Two species of the Mecyclothorax argutor (Sharp, 1903) species-group, M. neonomas sp. nov. and M. brunneonubiger sp. nov., are newly described from Mauna Loa volcano on the Island of Hawai‵i. Mecyclothorax neonomas is most similar morphologically to M. swezeyi Liebherr, 2008 of Mauna Kea and is therefore proposed as its adelphotaxon. Conversely, the adelphotaxon proposed for M. brunneonubiger is M. blackburnianus Liebherr, 2008, precinctive to Kohala volcano, Island of Hawai‵i. Based on the younger geological age of origin of Mauna Loa relative to Mauna Kea and Kohala, it is hypothesized these two newly described, sympatric species arose via progressive colonization of Mauna Loa during development of the geologically dynamic Island of Hawai‵i. A revised key to all Mecyclothorax species known from Hawai‵i Island is provided.

Of the 12 specimens of Calathus -like sphodrine beetles presently known from Baltic and Rovno amber deposits, 11 specimens were investigated using light microscopy, micro-CT scanning, and 3D imaging techniques. For the first time, many significant diagnostic characters of the external morphology and male and female genitalia of Eocene Sphodrini were studied in detail. Based on these data, three fossil species are diagnosed and placed in a natural group characterized by a derived pattern in elytral chaetotaxy and microsculpture and therefore the genus Quasicalathus Schmidt & Will, gen. nov. is described to comprise these species. Due to the presence of a styloid right paramere, Quasicalathus gen. nov. is considered a member of the sphodrine “P clade” of Ruiz et al. (2009). However, given the absence of synapomorphies of any species group of the P clade, the systematic position of Quasicalathus gen. nov. within this clade remains unresolved. The Baltic amber species Calathus elpis Ortuño & Arillo, 2009 is redescribed based on additional, fossil, non-holotype material and transferred to Quasicalathus gen. nov. Identification of the additional C. elpis fossil material remains slightly uncertain due to the non-availability of the holotype for direct comparison coupled with doubts regarding the accuracy of certain character states presented in its original description. Two species are newly described: Quasicalathus agonicollis Schmidt & Will, sp. nov., from Baltic amber, and Q. conservans Schmidt & Will, sp. nov., from Rovno amber.

We found distinct and consistently placed, species- and sex-specific abrasions of the cuticle on museum specimens of 14 species of the Pterostichus Bonelli, 1810 (Carabidae, Pterostichini) subgenusHypherpes Chaudoir, 1838. We deduced that these marks are generated during mating and, therefore, can be used to distinguish between preserved specimens of beetles that had previously mated at the time of capture and those that had not mated. In addition to describing and detailing the occurrence of the marks and providing evidence that they are the result of mating, we demonstrate their utility for inferring life history using a museum voucher collection. By scoring these indications of mating from pinned specimens, we describe life cycle patterns in two similar, relatively closely related and sympatric species of the subgenus Hypherpes, P.vicinus Mannerheim, 1843 and P.californicus (Dejean, 1828). Both were sampled during a pitfall trap study in Contra Costa, California, USA from 2014-2019 and deposited in the Essig Museum of Entomology, UC Berkeley. Both species had very low adult activity through the drought and end of drought period prior to the spring of 2017 and are significantly more abundant in the post-drought period. Based on mating marks, both species responded to accumulated precipitation ending the drought by the emergence of an active, mostly unmated cohort of adults. The spring activity peak, following the end of the drought, was dominated by unmarked and presumably unmated beetles, but samples from subsequent springs included a nearly equal mix of beetles showing mating marks and apparently unmated beetles. The beetle activity appears to correspond more with the accumulated rainfall of the preceding rainy season than with the rains of the sample year. Beetles sampled in autumn and winter (rainy season) predominantly show mating marks. The occurrence throughout the year of beetles that are marked as having mated is consistent with iteroparous beetles with a lifespan of more than one year and also consistent with dynamic phenotypic polyvariance in which the adult activity period is synchronised by adjusting development time. The dominant pattern fits with a life cycle that is typically annual univoltine, or possibly biennial semivoltine in dry years, rainy season breeding (autumn-winter) iteroparous, with adult summer aestivation and possibly facultative larval hibernation. However, unmarked and so apparently unmated individuals and teneral adults were captured during peak activity periods regardless of the season, suggesting that either the beetles diapause as teneral adults that then complete development and become active at various points during the year and/or there are multiple periods of breeding and oviposition each year in at least some portion of the population.

The Oodini precinctive to New Caledonia are reviewed with nine species recognized, of which seven are newly described in two genera. Five species are described in the genus Coptocarpus Chaudoir: C. microps sp. nov., C. erwini sp. nov., C. amieuensis sp. nov., C. magnus sp. nov., and C. lescheni sp. nov. In the genus Adelopomorpha Heller two species, A. tethys sp. nov. and A. tuberculata sp. nov., are described. In order to place cladistically the newly described species in a genus, a phylogenetic analysis of a matrix of 36 characters of adult morphology was conducted including exemplar species of three putative outgroup genera, six putative ingroup thryptocerine oodine genera, and all oodine species from New Caledonia. Results show support for Thryptocerina and monophyly of Adelopomorpha. Hoplolenus LaFerté-Sénectère is not monophyletic and Hoplolenus cyllodinus Fauvel is newly combined as Coptocarpus cyllodinus comb. nov. New Caledonian species of Coptocarpus form a clade, but the Australian species of the genus included in the analysis are rendered paraphyletic by African and Malagasy genera. Implications of this preliminary study for the classification of Oodini and trends in the evolution of the female reproductive tract are discussed. A key to the New Caledonian species of Oodini is provided.

The taxonomic position of Pristodactyla advena LeConte, 1848 (= "Acalathus" advena in the sense of previous authors) is discussed in light of a novel review of the morphological characters of Calathina and closely related taxa. All Acalathus Semenov, 1889 species and all other Dolichina share the distinct character state of having the sensory pits of the apical gonocoxites reduced or absent, while these pits are well-developed in P. advena. Therefore, P. advena is moved into the genus Calathus Bonelli, 1810 (Calathina), where it is placed in the molecular phylogeny of Ruiz et al. (2010). This move necessitates the description of Certocalathus subgen. n. for this species. Diagnostic characters of the new subgenus with respect to other Calathina and Dolichina beetles are presented. Given the lack of any clear synapomorphies, the subtribe Calathina is not obviously defined by morphology alone. However, recent molecular phylogenies indicate its monophyly is highly likely and therefore diagnostic morphological characters are polythetic. The states of selected morphological characters in Calathina and Dolichina taxa are provided as a summary for this and future studies.

A new species of Lobobrachus Sharp, 1885, Lobobrachus cleidecostae sp. nov., from Piauí state, Brazil, is described and illustrated. The genus and Lobobrachus lacerdae Sharp, 1885, are redescribed and the identity of L. alternans Tschitschérine, 1901, is discussed. Based on study of all available specimens and published descriptions it appears that L. alternans cannot be diagnosed and is a synonym of L. lacerdae. However, the syntypes of L. alternans cannot be located, thereby making a final decision on synonymy impossible to substantiate fully. Photographs of the aedeagi of L. lacerdae, L. cleidecostae, and specimens that best correspond to L. alternans, including those putatively identified by Tschitschérine, are presented for the first time.

Darlington described Tiferonia based on T. parva from New Guinea. In this review, Tiferonia leytensis sp. nov. is described from Leyte Island, Philippines, Tiferonia schoutedeni (Straneo, 1943) comb. nov. is transferred from Melanchrous Andrewes, and inclusion of Tiferonia brunnea (Jedlička, 1935) in the genus is confirmed. Characteristics of Tiferonia and genera that have been proposed as closely related to Tiferonia are discussed and a unique character, the post-ocular sulcus, shared among species of Tiferonia and Holconotus is proposed as a synapomorphy for these two genera. A key to identify adults of the four species of Tiferonia is provided.

Abstract Promecognathus (Carabidae) includes beetles that are specialist predators whose prey are polydesmidan millipedes that produce highly toxic hydrogen cyanide and benzaldehyde as a defense, and it is unknown how Promecognathus overcomes these chemicals. We observed Promecognathus laevissimus (Dejean, 1829) and P. crassus (LeConte, 1868) in the laboratory and found that they did not use behaviors to avoid the chemical defenses of their prey, Xystocheir dissecta (Wood, 1867) (Polydesmida: Xystodesmidae). We tested benzaldehyde as a feeding deterrent and found noticeable deterrence in all carabid beetles tested except Promecognathus species and Metrius contractus (Eschscholtz, 1829). A total of 18 carabid species were exposed to cyanide vapors in an enclosed chamber for 10 min to determine their relative tolerances. Promecognathus and M. contractus were unaffected by HCN exposures 7–15 times greater than quantities that knocked down all other species. Promecognathus laevissimus and M. contractus were then exposed to high levels of HCN for 2 h, and while individuals of M. contractus succumbed, all P. laevissimus were still moving after 2 h. It is possible that Promecognathus evolved a high tolerance to cyanide as part of a suite of adaptations related to millipede predation. However, we have no plausible explanation for the high tolerance in Metrius, for which there is no evidence of millipede feeding. This is the first documented case of predatory insects that exhibit high tolerance and potential resistance to cyanide. Possibly, these beetles have a detoxification mechanism that is not cyanide specific, as their tolerance level far exceeds any dose they would encounter in their natural habitat.

Hydrocyanic acid (HCN) is a well-known defensive allomone in the chemical arsenal of millipedes in the order Polydesmida. The presence of HCN in the headspace vapor of adult Xystocheir dissecta (Wood, 1867), a common millipede from the San Francisco Bay Area, was traced by laser desorption/ionization-mass spectrometry (LDI-MS). To accomplish this, the headspace vapor surrounding caged, live millipedes was allowed to diffuse passively over gold-nanoparticle (AuNP) deposits placed at various distances from the emitting source. The stainless steel plates with AuNP deposits were removed and irradiated by a 355-nm laser. The gaseous ions generated in this way were detected by time-of-flight mass spectrometry. The intensity of the mass spectrometric peak detected at m/z 249 for the Au(CN)(2)(-) complex anion was compared to that of the residual Au- signal (m/z 197). Using this procedure, HCN vapors produced by the live millipedes could be detected up to 50 cm away from the source. Furthermore, the addition of H2O2, as an internal oxygen source for the gold cyanidation reaction that takes place in the AuNP deposits, significantly increased the detection sensitivity. Using the modified H2O2 addition procedure, HCN could now be detected at 80 cm from the source. Moreover, we found a decreasing intensity ratio of the Au(CN)(2)(-)/Au- signals as the distance from the emitting source increased, following an exponential-decay distribution as predicted by Fick's law of diffusion. Graphical abstract

A sulfur-containing compound causes the foul smell of the defensive pygidial gland fluid of Ceroglossus buqueti Laporte and Ceroglossus magellanicus Gehin. This compound was identified as 3-methyl-1-(methylthio)-2-butene by a comparison of its mass spectrum, and chromatographic properties with those of a chemically synthesized standard. Although a few sulfur compounds are known from insect secretions, this sulfur-bearing isoprene derivative has not been characterized previously from any arthropod source. Additional components in the defensive section include acetic, propanoic, isobutyric, butanoic, methacrylic, ethacrylic, tiglic and benzoic acids, and 11-tricosene. Samples prepared from specimens of Ceroglossus chilensis Eschscholtz showed methacrylic, ethacrylic, and other acids. However, 3-methyl-1-(methylthio)-2-butene was not detected in the defensive fluid of C. chilensis.

The Australian genus Pediomorphus Chaudoir, 1878 is reviewed and eight new species are described: Pediomorphus maximus Will, new species and Pediomorphus crenulatus Will, new species from New South Wales; Pediomorphus minor Will, new species from South Australia; Pediomorphus punctatus Will, new species from Northern Territory; Pediomorphus storeyi Will, new species from Queensland; Pediomorphus semilaevis Will, new species from Northern Territory and Queensland; Pediomorphus robustus Will, new species from Queensland and Western Australia; and Pediomorphus obtusus Will, new species from Queensland, Northern Territory, and Western Australia. A key to the 13 species of the genus is provided.

Urban ecosystems, as mosaics of residential, industrial, commercial, and agricultural land, present challenges for species survival due to impervious surface, degradation, fragmentation, and modification of natural habitat, pollution, and introduced species. Some urban habitats, such as community gardens, support biodiversity and promote ecosystem services. In gardens, local factors (e.g., vegetation, groundcover) and landscape surroundings (e.g., agriculture, built or impervious cover) may influence species abundance, richness, and functional traits that are present. We examined which local and landscape factors within 19 community gardens in the California central coast influence ground beetle (Carabidae) activity density, species richness, functional group richness, and functional traits-body size, wing morphology, and dispersal ability. Gardens with higher crop richness and that are surrounded by agricultural land had greater carabid activity density, while species and functional group richness did not respond to any local or landscape factor. Gardens with more leaf litter had lower carabid activity, and gardens with more leaf litter tended to have more larger carabids. Changes in local (floral abundance, ground cover) and landscape (urban land cover) factors also influenced the distribution of individuals with certain wing morphology and body size traits. Thus, both local and landscape factors influence the taxonomic and functional traits of carabid communities, with potential implications for pest control services that are provided by carabids.