We describe a new genus and new species of pselaphine rove beetle, Batriscydmaenus tishechkini Parker and Owens, from lowland Panamanian rainforest. The new taxon marks a radical departure from the basic pselaphine anatomical groundplan, with a globose body shape and a dramatic reduction of foveae, sulci and striae—features that are considered plesiomorphic in Pselaphinae. This overt simplification of the integument is typical of myrmecophile and termitophile taxa within Pselaphinae. A probable symbiotic lifestyle of members of Batriscydmaenus is further implied by their compact antennae and the presence of suberect, spatulate setae covering the dorsum. The convergent evolution of this trend towards character loss in inquilinous pselaphines implies a “reductive” ecomorph, specialized for living inside social insect societies in part by abandoning many cuticular features of free-living pselaphines. Batriscydmaenus represents possibly the most extreme manifestation of this ecomorph known to date. Reductive anatomy poses a challenge to taxonomic assignment, but we confirm molecularly that the genus belongs to the tribe Batrisini, using gene fragments amplified from a paratype.

A new southern Chinese genus and species, Loeblibatrus yunnanus Yin, new genus and new species, of the staphylinid subfamily Pselaphinae is described and illustrated. Most individuals were collected from colonies of Ectomomyrmex Mayr (Hymenoptera: Formicidae) beneath stones. Adults of L. yunnanus exhibit a strong reduction of external features (e.g., foveae, carinae, sulci) that are typical of myrmecophilous pselaphines. Loeblibatrus is assigned to the supertribe Batrisitae: tribe Batrisini based on the presence of four short, thickened setae at the anterior margin of the labrum, a probable synapomorphy for the supertribe. Within Batrisini, L. yunnanus externally resembles members of the Oriental genera Batrisopsis Raffray and Ophelius Raffray, and, surprisingly, Batriscydmaenus tishechkini Parker and Owens from Central America, which is described in a companion paper. This similarity in general habitus may represent morphological convergence resulting from these beetles' shared symbiotic lifestyles with ants.

A new species of Sandalus Knoch from Florida and Alabama is described and illustrated. A key to the described species of the eastern USA is provided.

The genus Alaudes Horn is revised and placed in a new subtribe, Alaudina. The genus includes A. singularis Horn, A. setigera Blaisdell, A. alternata Fall, and the following new species: A. mojavensis Aalbu, Caterino, and Smith (Mojave Desert: California and Arizona), A. coloradoensis Aalbu, Caterino, and Smith (Colorado Desert, California), A. moenkopii Aalbu, Caterino, and Smith (Colorado Plateau, northern Arizona and southern Utah), A. californicus Aalbu, Caterino, and Smith (Central Valley, California), and A. vizcainensis Aalbu, Caterino, and Smith (Vizcaino Desert: Baja California and Baja California Sur, Mexico). Alaudes fallax Fall, A. testacea Blaisdell, and A. squamosa Blaisdell are placed as new synonyms of A. singularis Horn. The subtribe Alaudina is described and diagnosed. A key is provided to the known Alaudes species. The biology of the genus is discussed, including host preference, immatures, life expectancy, and habitat diversity. All Alaudes species are associated with various species of ants (Formicidae), and some degree of colony integration is indicated by their possession of trichomes. The species span a range of habitats from extreme deserts to midelevation mesic montane forests. The immature stages are not known.

The Neotropical species Enneboeus marmoratus Champion, 1893 is reported from the USA based on the collection of three specimens in urban San Francisco, California, representing a new country record for the species. Additional specimens were observed and photographed at the same locality on various dates during August to October 2017. This is likely a recent introduction, and its level of establishment is unknown. This also represents the first record of Archeocrypticidae from California. Additional records of the only other known North American (north of Mexico) species, Enneboeus caseyiKaszab, 1981, are provided. A world catalog of this small group of beetles is included.

The genera Dysanellus Bernhauer and Torobus Herman are illustrated and reviewed. Two species are recognized in Dysanellus, D. bruchi Bernhauer and D. transverserugosus Bernhauer. Two valid species are recognized in Torobus as well, T. laetipes (Bernhauer) and T. purpurascens (Nordmann) after the following taxonomic changes. Trigonurus brasilianus Bernhauer is recognized as a junior synonym of Staphylinus purpurascens Nordmann, new synonymy. Torobus mautnermarkhofi (Scheerpeltz) is transferred to Scariphaeus Erichson as Scariphaeus mautnermarkhofi, new combination. Synoptic catalogue entries are provided for all species that have ever been placed in either Dysanellus or Torobus to clarify the status of those species.

An analysis based on fossilized animal tracks, oral tradition, archaeological findings, and the distribution and biology of dung beetles is presented to suggest that Copris subpunctatus Gillet (Coleoptera: Scarabaeidae) probably fed on bison dung and switched to cow dung after cattle were introduced by the Spanish colonizing effort. This transition probably took place before the bison apparently became extinguished in Costa Rica at the end of 19^th or beginning of the 20^th century.

Stockwellius fasciatus Anderson, a new genus and new species of Litosomina, is described from Cerro Campana, Panama. The genus and species are characterized by large size (22 mm), rhomboidal scutellum, elytral pattern with band of condensed golden micropilosity, toothed femora, dorsal apex of rostrum deeply medially emarginate, and the short, dorsally humped rostrum with an elongate patch of dense, golden micropilosity laterally below the dorsal hump. Only a single adult female collected in 1985 is known from this popular collecting locality. No information on natural history is available. A revised key to the genera of Neotropical Litosomina is presented.

Study of type specimens for the two species originally described in the presumed New World genus MycophtorusLacordaire, 1842 (Coleoptera: Erotylidae: Erotylinae: Tritomini) revealed they belong to different genera from different continents. Mycopthorus melanocerusLacordaire, 1842, the type species of Mycophtorus, is conspecific with Neomycotretus hilaris (Arrow, 1917), the type species of NeomycotretusDeelder, 1942. These findings necessitate a transfer of the generic name and type species of Mycophtorus to Neomycotretus, resulting in 23 new combinations for species of this African taxon. In addition, Petaloscelis hilarisArrow, 1917 and Neomycotretus liberianusDeelder, 1942 are synonymized under M. melanocerus, new synonymies. Having the same type species, Neomycotretus Deelder is synonymized with Mycophtorus Lacordaire, new synonymy, the latter having priority. Mycophtorus peruvianusKirsch, 1876 belongs in the genus MycotretusLacordaire, 1842 (sensu lato), becoming Mycotretus peruvianus (Kirsch), new combination. The remaining two Neotropical species previously in “Mycophtorus” are placed in Myceporthus Skelley and Powell, new genus, with the type species here designated as Mycophtorus pauperculusLacordaire, 1842.

A spider beetle, Mezium colossosetum Philips and Dickmann, new species, is described from the Western Cape, South Africa. We also propose the synonymy of Mezium namibiensis Bellés with Mezium gracilicorne Pic and discuss the possibility of a second synonym within the genus. Documentation of the variation within M. gracilicorne is illustrated and discussed. All distribution records known for the species of Mezium Curtis are listed, and the origin of the genus is hypothesized based on both morphological and preliminary molecular data.

The female of Tomarus rostratus Dupuis is described for the first time, and the first record for the species in Chile is presented. Tomarus rosettae (Endrödi, 1968) is proposed as a junior synonym of Tomarus pumilus (Prell, 1937). The recently designated subspecies Tomarus maimon fossatorBurmeister, 1847 is a synonym of its nominal species. New records are provided for the following species: Tomarus cuniculus (Fabricius, 1801), Tomarus selanderi (Cartwright, 1959), Tomarus similis (Endrödi, 1968), and Tomarus rubripes (Boheman, 1858).

Proximate and elemental compositions of five soil-dwelling scarabs, Lepidiota mansueta Burmeister, Lepidiota albistigma Burmeister, Xylotrupes gideon (Linnaeus), Catharsius molossus (Linnaeus), and Sophrops iridipennis (Brenske), were assessed. Nutrient content varied widely, and the ranges of proximate contents were as follows: moisture (2.04–2.55%), crude protein (68.54–79.33%), crude fat (4.00–5.50%), crude fibre (5.16–8.28%), total mineral (0.80–4.98%), and carbohydrate (5.28–11.84%). Caloric content was greater in L. mansueta (379.29 kcal) compared to the other four species. The caloric contents of X. gideon (375.54 kcal) and C. molossus (375.19 kcal) were at par but significantly higher than those of L. albistigma (371.04 kcal) and S. iridipennis (361.55 kcal). Sodium content ranged 23.16–35.91 mg/100 g; potassium 14.20–44.33 mg/100 g; calcium 23.33–33.37 mg/100 g; iron 1.41–37.05 mg/100 g; copper 2.01–16.13 mg/100 g; zinc 2.38–15.86 mg/100 g; and manganese 1.09–19.66 mg/100 g. The phenol, flavonoid, and antioxidant activities of L. mansueta and L. albistigma were 4.00 and 6.42 mg catechol equivalent/g, 1.59 and 3.71 mg quercetin equivalent/g, 22.60, and 28.20%(DPPH activity), respectively. Tannin content was higher in L. albistigma (13.30 mg/g) than in L. mansueta (3.24 mg/g). Based on our study, these scarab species can be explored as food supplements and nutraceutical resources in ensuring food security.

Males of Photinus pyralis (Linnaeus) and Photinus sabulosus Green were the primary victims of spider attacks at a field site in northern Virginia from 1 July 2017 to 21 August 2017. Males of these species, as is true for other members of the genus, appear to be at far greater risk of predation than are females, a reflection of the mating system of fireflies in which males fly in search of females that are largely sedentary during the mating period. Once trapped, males are sometimes eaten by kleptoparasitic fireflies in the genus Photuris Dejean, which can usually steal wrapped prey from the spiders that have captured them, as has been demonstrated elsewhere as well, but occasionally fall prey to others of their genus that have been attracted to spider webs.

We report 110 species of Buprestidae from the state of Louisiana, 103 species based on 5,047 specimens examined and seven from previous literature records. Fifteen new state records are reported, including the first published records of Agrilus planipennis Fairmaire, 1888 (emerald ash borer), which is now established in the northern parishes of the state. Two new state records are based on specimens taken during biomonitoring surveys using the buprestid specialist wasp Cerceris fumipennis (Say, 1837). Potential larval and host plants of buprestid species in Louisiana and collection date ranges of specimens examined are provided.

Aporrhipis flexilisPascoe, 1887 is the sole species of a monospecific genus of beetles from Brazil, originally described in the family Ripiphoridae. Despite the fact that this genus was moved to Lycidae, its correct tribal placement remains uncertain. In this study, A. flexilis is redescribed, its tribal placement is discussed, and it is tentatively placed within the Calopterini, Acroleptina. The problems of distinguishing the Acroleptina from the Leptolycini are highlighted by this case, and a plea is made for additional specimens to help resolve this conundrum.