A cladistic analysis based on 21 characters from the external morphology and male genitalia was undertaken in order to determine the status of the flea subgenera Ctenophthalmus (Alloctenus) and C. (Nearctoctenophthalmus). As a result of the analysis, Ctenophthalmus (Alloctenus) (=Nearctoctenophthalmus, new synonym) comprises nine species (in phylogenetic sequence): C. pseudagyrtes, C. sanborni, C. micropus, new status (from subspecies of C. pseudagyrtes), C. haagi, C. tecpin new species, C. caballeroi, C. cryptotis, C. expansus, and C. myodosus, new status (from subspecies of C. expansus). Biogeographic data indicate that two species (C. pseudagyrtes and C. micropus) are widespread in both the Nearctic and Neotropical regions, another (C. tecpin) is exclusively Nearctic, whereas the remaining six species are exclusively Neotropical. Within the latter, the monophyletic clade including those species previously assigned to C.(Alloctenus) is endemic to the Transvolcanic Mexican Belt. Host data indicate that the most primitive species are basically parasites of sigmodontine mice (Rodentia: Muridae)—secondarily associated with Talpidae and Soricidae (Insectivora)—whereas the most derived species are exclusive parasites of the shrew genus Cryptotis (Insectivora: Soricidae).

The South American tribe Nycteliini (Pimeliinae) comprises nine genera distributed from central Peru to southern Argentina and Chile: Gyriosomus Guérin-Méneville, Pilobalia Burmeister, Entomoderes Solier, Nyctelia Latreille, Epipedonota Solier, Psectrascelis Solier, Scelidospecta Kulzer, Auladera Solier, and Mitragenius Solier. A cladistic analysis of the genera of Nycteliini is conducted, including 93 characters and 11 terminal taxa because two of the genera are treated as two terminal units: Epipedonota and Mitragenius. The one most parsimonious cladogram obtained shows that Nycteliini is a monophyletic group characterized by two synapomorphies from internal morphology and female genitalia. The generic relationships are resolved and the genus Mitragenius appears as non-monophyletic. The results suggest that the species of Nycteliini should be arranged best in 11 genera. The study confirms the importance of the use of new characters, such as genital structures and internal morphology in the classification of Tenebrionidae. The paper includes a discussion of the phylogeny of the tribe and information on evolution of thoracic endosternites was used along the tree to analyze evolutionary patterns.

Adult and mature larval characters of Blepharida atripennis, B. rhois, B. sacra, Diamphidia sp., Euplectroscelis xanti, Ophrida marmorea Podontia affinis, P. lutea and P. dalmani, were studied as representatives of their respective genera or subgenera from the Blepharida-Group of approximately 16 genera worldwide, presumed to be related. The similarities and relationships of these and other genera based on adult and larval morphology and biology are discussed. The mature larvae of these nine species are illustrated in detail, three for the first time (Ophrida marmorea, Euplectroscelis xanti, and Diamphidia sp.). Adult external morphology and the metafemoral spring were compared and indicated several overlapping similarities. Some discussion of the classification of the Galerucinae and Alticinae is provided.

The genera Falsopraocis Kulzer and Antofagapraocis n. gen. (Pimeliinae: Praocini), distributed in the high Andes of central and northern Argentina and Chile, are revised. A cladistic analysis of five species is presented. Cladistic analysis reveals that Falsopraocis is not monophyletic: one species formerly assigned to Falsopraocis together with a new species constitute the new genus, Antofagapraocis. Falsopraocis consists of three species: F. ricardae (Solier), F. weiseri Kulzer, and F. australis n. sp.; Antofagapraocis includes two species: A. subnudus (Kulzer) n. comb. (type species) and A. brevipilis n. sp. A cladogram, redescriptions or descriptions of the genera and their five species, keys, illustrations of body and genitalic features, and a distribution map are included.

The genus Thylacoderes Solier (Pimeliinae: Praocini), distributed in central and northern Argentina, is revised. A cladistic analysis of four species is presented including: Thylacoderes sphaericus n. sp., T. seminulum (Burmeister), T. eumolpioides Solier, and T. costatus n. sp. A lectotype is designated for Platyholmus seminulum Burmeister. The cladistic analysis shows that Thylacoderes comprises a natural group of species, characterized by several synapomorphies from the external morphology and male genitalia. A redescription of the genus, redescriptions or descriptions of the four species, a key, illustrations of external morphology, internal skeletal anatomy and genitalic features, a cladogram, and a distribution map are included.

Xenochalepus (Neochalepus) hespenheidei new species from Costa Rica and Panama is described and illustrated.

A new Neotropical member of the Drosophila obscura species group from El Salvador and Honduras, Drosophila maya, is described. This species belongs to the New World pseudoobscura subgroup and, based on a variety of internal and external morphological characters, is most closely related to D. lowei. This species is distinguished from other members of the pseudoobscura subgroup by the shape of the hypandrium and by having fewer teeth on the sex combs. Ecologically, D. maya inhabits cloud forests at elevations around 2,000 m in El Salvador and Honduras. A key to eight members of the obscura species group which have been recorded in and near the Neotropical region is presented.

Acamanthina, new genus, is described and illustrated from Chile and Argentina, and includes two species: A. acmanthes (Meyrick, 1931) (type species), new combination, and A. albipuncta, new species. Acmanthina can be distinguished from all other genera in Euliini by two external and one genitalia feature of the males: the absence of elongate scaling in the basal portion of the hindwing along veins 1A 2A and CuP (present in the female), the possession of a fascicle of 17–20 extremely long sex scales (=hairpencil) concealed in a deep fold along the basal three-fifths of hindwing vein CuP, and the deep mesal excavation of the juxta. The new genus appears to be most closely related to Haemateulia Razowski.

Trachinocoris crassoides, new species from Brazil, Paradema renocula, new species from Venezuela, and Paradema slateri, new species from Ecuador, are described and figured. Paradema bathydemoides Slater is redescribed and figured. Figures of morphological details and a discussion of phylogenetic relationships are included.

Twelve species in eight genera of the New World subfamily Larginae are discussed. The following species are redescribed and/or compared with their original descriptions: Acinocoris calidus (F.), A. decoratus Brailovsky and Barrera, A. includens Walker, A. lunaris (Gmelin), A. stehliki Van Doesburg, Astemma nigrocapitata Brailovsky and Barrera, Fibrenus bullatus White, Stenomacra marginella Herrich-Schaeffer, Therenais constricta Stål, and Vasarhelyecoris ophthalmicus Brailovsky and Barrerra. The measurements of the following species were compared with published measurements: Acinocoris calidus, A. decoratus, A. lunaris, A. stehliki, Astemma nigrocapitata, and Fibrenus bullatus. Instars of the following species are described: Largulus parallelus Hussey (third and fifth instars), and Thaumastaneis montandoni Kirkaldy and Edwards (fifth instar); the fifth instar of Largulus parallelus is figured. The following are new country records: Acinocoris elegans Van Doesburg: Peru; A. includens: Venezuela; A. lunaris: Bolivia; A. stehliki: Venezuela; Therenais constricta: Ecuador; and Thaumastaneis montandoni: Bolivia.

Xyrophoreus cristatus new species, is described from South India; new distributional data for X. tonsor Breddin is included; dorsal view illustrations and drawings of head, pronotum, antennal segments and hind leg are provided.

The mirine plant bug genus Chilocrates Horváth, previously synonymized with Deraeocoris Kirschbaum in the subfamily Deraeocorinae, is restored and transferred to the tribe Mirini of the Mirinae. Two species, Chilocrates patulus (Walker, 1873) and Chilocrates chelonia (Distant, 1904), the only confirmed members of the genus, are diagnosed with respect to color pattern and genitalia, and reported from Bhutan and Nepal for the first time. The following synonymies and taxonomic changes are established: Chilocrates Horváth, 1889 = Shana Kirkaldy, 1902 = Liocoridea Reuter, 1903 = Gismunda Distant, 1904; Chilocrates patulus (Walker, 1873) = Chilocrates lenzii Horváth, 1889 = Shana ravana Kirkaldy, 1902 = Liocoridea mutabilis Reuter, 1903 (including var. nigra Reuter, 1903 and var. testacea Reuter, 1903) = Deraeocoris variabilis Distant, 1904 = Gismunda modesta Distant, 1909 = Lygus szechuanensis Hsiao, 1941 (including var. ruficephalus Hsiao, 1941); and Chilocrates chelonia (Distant, 1904) = Deraeocoris variabilis ‘var. a-d’. Lectotypes of Gismunda chelonia and Deraeocoris variabilis are designated.

Salamancaniella, new genus, is erected to include one species originally described in Meropachus De Castelnau and later transferred to Hirilcus Stål as the binominal H. alternatus (Dallas 1852); new distributional records are given; and habitus illustrations and drawings of male and female genitalia, hind leg, metathoracic peritreme and thoracic mesosternum and metasternum are provided. The genus is compared to Hirilcus and Meropachys.

Nymphs of the leafhopper tribe Xestocephalini, not previously observed in nature, were assumed to be ground-dwelling myrmecophiles. Numerous nymphs of all instars of X. desertorum (Berg) were collected from the ground of a roadside meadow in Illinois, U.S.A., with a vacuum collector. Neither nymphs, nor adults appeared to be associated with ant nests. When kept in the laboratory, the nymphs fed on grass roots, and the adults both on roots and green parts of grasses; females oviposited in dead grass roots. The species is bivoltine in Illinois, with the egg stage overwintering. Like many other leafhoppers, after each molt, both nymphs and adults of X. desertorum cover the fresh integument with brochosomes: secretory particles produced in the Malpighian tubules. These poorly known behaviors are described and illustrated. Unlike in leafhoppers studied previously, the brochosomes of X. desertorum nymphs and adults differ in structure.

The taxonomy of the masarine genus Ceramiopsis is reviewed, and two described species are separated: gestroi Zavattari and paraguayensis Bertoni, revised status.