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Rhagovelia Mayr, 1865 (Hemiptera: Heteroptera: Veliidae) is a species-rich and widespread genus of semiaquatic bugs, found both in freshwater and coastal marine environments. Despite the considerable number of species recorded from Brazil, the northern and northeastern regions of the country remain poorly explored. We present here the description of a new species of the angustipes complex, Rhagovelia leilae Paiva, Rodrigues & Moreira, sp. nov., and new records for the following species: R. brunae Magalhães & Moreira, 2016; R. evidis Bacon, 1948; R. hambletoni Drake & Harris, 1933; R. humboldti Polhemus, 1997; R. tenuipes Champion, 1898; and R. whitei (Breddin, 1898). These include the first records of species of Rhagovelia from the states of Pernambuco and Tocantins, and also increase the number of known species from the states of Alagoas, Bahia, and Maranhão to six, five and six, respectively.

Gerromorpha (Hemiptera: Heteroptera) comprises more than 2100 species of semiaquatic bugs, most of which have the ability to walk on the surface of the water. So far, 238 species have been recorded from Brazil, but several portions of the country remain poorly explored. The Metropolitan Region of Santarém (MRS), Pará State, Brazil, lacks faunistic and taxonomic studies concerning this group and the local fauna is under threat due to human actions.Aiming to fill gaps concerning the diversity and distribution of Gerromorpha in the Amazon, a survey of the semi-aquatic bugs from the MRS is presented. Collections were made in 33 aquatic ecosystems in the different phytophysiognomies within this area from July 2019 to October 2020. As a result, a checklist with 44 species recorded from the three municipalities of the MRS is presented. Furthermore, three new species of the genusMicroveliaWestwood, 1834 (M. belterrensissp. nov.,M. hamadaesp. nov.andM. sousorumsp. nov.) are described, two species are recorded for the first time from Brazil (Microvelia aschnakiranaeMakhan, 2014 andRhagovelia graziaeGalindo-Malagón, Morales & Moreira, 2021), two from Pará State (Microvelia longipesUhler, 1894 andParavelia dilatataPolhemus & Polhemus, 1984) and 15 from the MRS (Brachymetra lataShaw, 1933,B. shawiHungerford & Matsuda, 1957,Tachygerris adamsoni(Drake, 1942),Microvelia pulchellaWestwood, 1834,Rhagovelia brunaeMagalhães & Moreira, 2016,R. evidisBacon, 1948,R. jubataBacon, 1948,Callivelia conata(Hungerford, 1929),Oiovelia cunucunumanaDrake & Maldonado-Capriles, 1952,Paravelia bullialataPolhemus & Polhemus, 1984,Stridulivelia alia(Drake, 1957),S. stridulata(Hungerford, 1929),S. strigosa(Hungerford, 1929),S. tersa(Drake & Harris, 1941) andS. transversa(Hungerford, 1929)).

The new species Paravelia ameliae (Heteroptera: Veliidae) is described based on macropterous specimens from the Department of Putumayo, in the Amazonian region of Colombia. The new species can be distinguished from all congeners mainly by the bicolored pronotum (dark-brown on the anterior two-thirds and light-brown posteriorly); the absence of distinct pruinosity or silvery patches on the anterior lobe of the pronotum; the basal macula of the forewing small and roughly ovate; the grasping comb of the male fore tibia occupying more than half of its length; the male hind femur with a row of 15 spines on the basal two-thirds; and the male paramere notched basally on its dorsal surface. Furthermore, this species displays sexual dimorphism in body shape and in hind tibial length, with males having a slightly constricted mid-abdominal region and hind tibia distinctly longer than in females. Also, in order to describe external morphological characteristics not mentioned in previous studies, supplemental descriptions are provided for P. albotrimaculata (Kirkaldy, 1899), P. loutoni Polhemus, 2014, P. nieseri Moreira & Barbosa, 2012, and P. rotundanotata (Hungerford, 1930). Illustrations and a distribution map of all species treated here are presented.

Veredas environments play a critical role on the perennialization of streams in the Cerrado Biome, but alterations to their physiognomies are becoming increasingly more common, which directly affects abiotic variation and the structure of biological communities. Our study evaluates the effect of abiotic variations and environmental alterations upon the abundance, richness, and composition of species of semiaquatic bugs, where we test whether there are significant differences in conserved and altered veredas. Species richness was higher on altered veredas and there was no difference in abundance between altered and preserved veredas. The composition of conserved veredas was more homogeneous. Five species were associated with altered veredas and one to conserved areas. There were abiotic changes in the veredas that affected the abundance, richness, and/or composition of Gerromorpha. Ease of access to soil usage and to water for farming activities and pasture might be the main factors contributing to the alteration of veredas in this region. Gerromorpha community structure was modified by the environmental passive in areas of veredas, thus allowing to measure the degree of alterations to these systems, being a useful tool for monitoring and conservation.

Made available in DSpace on 2020-12-10T20:07:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-07-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) Platygerris White comprises true bugs that inhabit the surface of water in moderate to fast-flowing freshwater habitats. This genus differs from Cylindrostethus Mayr and Potamobates Champion (Gerridae: Cylindrostethinae) by having a short and flattened body; the mandibular and maxillary plates fused; and the omphalium, lateral groove, and lateral evaporatorium of the scent apparatus inconspicuous. In this paper, we redescribe Platygerris, describe two new species from Colombia, and redescribe P. asymmetricus Hungerford, P. caeruleus Champion and P. depressus White. In addition, we present an updated identification key to the species of the genus. For the first time, the cuticular structure is described for the genus based on electron microscopy. Univ Estadual Paulista, Dept Ciencias Biol, Lab Biol Aquat, Assis, SP, Brazil Univ Pedagog & Tecnol Colombia, Museo Hist Nat Luis Gonzalo Andrade, Lab Entomol, Grp Invest Sistemat Biol, Tunja, BY, Colombia Fundacao Oswaldo Cruz, Lab Biodiversidade Entomol, Inst Oswaldo Cruz, Rio De Janeiro, RJ, Brazil Univ Estadual Paulista, Dept Ciencias Biol, Lab Biol Aquat, Assis, SP, Brazil FAPESP: 2013/16367-0 FAPESP: 2015/09491-2 FAPERJ: 210.508/2016 FAPERJ: 202.551/2017 FAPERJ: 203.207/2017 CNPq: 305275/2014-3 FAPESP: 12/21196-8

A new Saldidae (MCT 6959-I) from the Crato Formation (Lower Cretaceous, late Aptian), Santana Group, Araripe Basin (northeastern Brazil) is described and illustrated.Olindasalda gondwanican. gen. n. sp. is the first fossil Saldidae recorded from the Gondwanan supercontinent. The new genus can be distinguished from other members of the subfamily Chiloxanthinae by its small (4.49 mm) and oval-elongated body, absence of spots on the corium of the hemelytron, long R vein, and much-reduced first cell of the membrane. Remarks on the geology of the type locality and a comparison of the new genus with other saldids are provided.UUID:http://zoobank.org/5ef8db72-3d7c-4de0-9a7c-e8fd80a9c8ba

We investigated the phylogenetic relationships among seven of the ten Halobatinae genera (Heteroptera: Gerridae) based on COI+II, 16S rRNA, and 28S rRNA genes. Our analyses recovered monophyly of Halobatinae, and suggested paraphyly of Metrocorini caused by the position of Ventidius and Esakia. Since our phylogenies did not infer monophyly of the subgenus Halobates (s.str.) within Halobatini, we synonymized Austrobates and Halobates (Hilliella) with Halobates. We confirmed that (1) the limnic lifestyle of Metrocorini was ancestral in Halobatinae, (2) the marine lifestyle evolved only once in the common ancestor of Asclepios + Halobates, (3) the limnic lifestyle of some members of Halobates was independently derived from marine ancestors, and that (4) the open ocean was colonized at least three times in Halobates. A catalogue of Halobatinae organized according to an updated classification is presented, including all known geographic distributions, bibliographical references, and additional notes to all species of the subfamily.

Rhagovelia medinae sp. nov., of the hambletoni group (angustipes complex), and R. utria sp. nov., of the hirtipes group (robusta complex), are described, illustrated, and compared with similar congeners. Based on the examination of type specimens, six new synonymies are proposed: R. elegans Uhler, 1894 = R. pediformis Padilla-Gil, 2010, syn. nov.; R. cauca Polhemus, 1997 = R. azulita Padilla-Gil, 2009, syn. nov., R. huila Padilla-Gil, 2009, syn. nov., R. oporapa Padilla-Gil, 2009, syn. nov, R. quilichaensis Padilla-Gil, 2011, syn. nov.; and R. gaigei, Drake & Hussey, 1947 = R. victoria Padilla-Gil, 2012 syn. nov. The first record from Colombia is presented for R. trailii (White, 1879), and the distributions of the following species are extended in the country: R. cali Polhemus, 1997, R. castanea Gould, 1931, R. cauca Polhemus, 1997, R. gaigei Drake & Hussey, 1957, R. elegans Uhler, 1894, R. femoralis Champion, 1898, R. malkini Polhemus, 1997, R. perija Polhemus, 1997, R. sinuata Gould, 1931, R. venezuelana Polhemus, 1997, R. williamsi Gould, 1931, and R. zeteki Drake, 1953.

Key innovations enable access to new adaptive zones and are often linked to increased species diversification. As such, they have attracted much attention, yet their concrete consequences on the subsequent evolutionary trajectory and diversification of the bearing lineages remain unclear. The monophyletic group of water striders and relatives (Hemiptera: Heteroptera: Gerromorpha) represent a group of insects that transited to live on the water-air interface and diversified to occupy ponds, puddles, streams, mangroves and even oceans. This lineage offers an excellent model to study the patterns and processes underlying species diversification following the conquest of new adaptive zones. However, such studies require a reliable and comprehensive phylogeny of the infraorder. Based on whole transcriptomic datasets of 97 species and fossil records, we reconstructed a new phylogeny of the Gerromorpha that resolved inconsistencies and uncovered strong support for previously unknown relationships between some important taxa. We then used this phylogeny to reconstruct the ancestral state of a set of adaptations associated with water surface invasion (fluid locomotion, dispersal and transition to saline waters) and sexual dimorphism. Our results uncovered important patterns and dynamics of phenotypic evolution revealing how the initial event of water surface invasion enabled multiple subsequent transitions to new adaptive zones, representing distinct niches of water surfaces, and further diversification of the group. This phylogeny and the associated transcriptomic datasets constitute highly valuable resources, making Gerromorpha an attractive model lineage to study phenotypic evolution.

Triatoma sordida is among the main Brazilian species considered as Chagas disease vectors. The genetic studies are directed mainly to phylogenetic questions because this species possibly have suffered cryptic speciation. Furthermore, there are few studies that analyzed the structure and genetic variability of specimens from Brazil and that showed low genetic diversity and strong genetic structuring of the population samples. Therefore, because of great epidemiological importance of T. sordida and mainly the restriction of genetic characterization of this vector only for populations of Minas Gerais state, this article performs a genetic analysis of the T. sordida from seven different Brazilian states (representing different biomes), by means of cytogenetic markers. All analyzed specimens presents the same cytogenetic characteristics: early meiotic prophase with several heterochromatic bodies dispersed in the nucleus (CG-rich), being one of them formed by the associated sex chromosomes surrounded by some autosomal heterochromatic regions, meiotic metaphase with most autosomal pairs exhibiting a C-heterochromatic block in one chromosomal end (CG-rich), Y sex chromosome fully heterochromatin (AT-rich), and X chromosome may present a small C-block (CG-rich). These results are important because the chromosomal markers enable to confirm and expand the low genetic diversity for all Brazilian states occupied by T. sordida, suggesting that all Brazilian populations were originated from a small ancestral population and possibly dispersed to other biomes by founder effect. In addition, we suggest that T. sordida from Brazil are not suffering cryptic speciation and we confirm the classification of all Brazilian examples as T. sordida sensu stricto.

A new genus of Gerridae (Insecta, Hemiptera, Heteroptera) in the subfamily Trepobatinae, Telmatometropsisgen. nov., with a single included species, T. fredyisp. nov., is described from the Colombian Pacific region. Representatives of the new genus were collected in mangrove lagoons of Buenaventura Bay, Valle del Cauca Department. The new genus can be diagnosed by the relative proportions of the antennomeres, the shape of the male fore tarsus, and by the black markings on the head, thorax and abdomen.

Water striders of the genus Rhagovelia Mayr, 1865 (Insecta: Hemiptera: Veliidae) have colonized the water surface mainly in lotic freshwater systems, but also in coastal marine environments. They are characterized by the swimming fan in the distal tarsomere of the middle leg that allows them to quickly maneuver. In the Americas, it was subdivided into four monophyletic complexes (angustipes, collaris, obesa and robusta), one paraphyletic grade (abrupta), each with several groups of species, and one additional group (varipes). However, the taxonomy of this genus still has inconsistencies due to its morphological complexity and to the misinterpretation of characters. For this reason, we present a revision of the species of the angustipes complex occurring in Colombia. Material deposited in nine biological collections was examined, including several types. A total of 3,674 specimens were studied, belonging to 26 valid species, of which R. boyacensis sp. nov., R. graziae sp. nov. and R. molanoi sp. nov., are described as new; and R. angustipes Uhler, 1894 is recorded from the country for the first time. Furthermore, eleven species are redescribed and twelve are considered synonyms. Finally, a key to the species of the angustipes complex occurring in Colombia is presented, as well as updated distribution maps.

A survey of the semiaquatic bugs (Hemiptera: Heteroptera: Gerromorpha) from Alagoas and Sergipe, Northeast Brazil, is presented. Specimens have been obtained mainly during three expeditions carried out in 2018 and 2019. Individuals of 40 species, representing the following 18 genera and five families have been recorded: Brachymetra Mayr, 1865, Cylindrostethus Mayr, 1865, Limnogonus Stål, 1868, Neogerris Matsumura, 1913, Tachygerris Drake, 1957, Rheumatobates Bergroth, 1892, Halobatopsis Bianchi, 1896, Ovatametra Kenaga, 1942 (Gerridae); Lipogomphus Berg, 1879, Merragata White, 1877 (Hebridae); Hydrometra Latreille, 1797 (Hydrometridae); Mesovelia Mulsant & Rey, 1852 (Mesoveliidae); Husseyella Herring, 1955, Microvelia Westwood, 1834, Rhagovelia Mayr, 1865, Paravelia Breddin, 1898, Platyvelia Polhemus & Polhemus, 1993 and Stridulivelia Hungerford, 1929 (Veliidae). Alagoas and Sergipe have 35 and 31 new records, respectively. Rheumatobates trinitatis (China, 1943) and Rhagovelia plumbea Uhler, 1894 are recorded for the first time from Brazil.

Microvelia joceliae Magalhães & Moreira, sp. nov. is described and illustrated based on material from Parque Natural Municipal das Andorinhas, Minas Gerais State, in southeastern Brazil. The new species can be distinguished from congeners occurring in the region by the pronotum of the apterous form covering almost the entire thorax dorsally, proepisternum with black denticles, male abdominal segments V–VII ventrally depressed, shape of the asymmetrical parameres, and female abdominal laterotergites reflected over the mediotergites and almost touching over segments V–VII.

The Chilean fauna of water bugs comprises seven species of semi-aquatic bugs (Heteroptera: Gerromorpha), representing five genera, three tribes, four subfamilies and four families; and 27 species and one subspecies of aquatic bugs (Heteroptera: Nepomorpha), representing four subgenera, eight genera, three tribes, seven subfamilies, and five families. We compare the fauna with neighboring countries and find that several otherwise widespread and abundant taxa are missing in Chile, but that Chepuvelia usingeri China, 1963 (Macroveliidae), Microvelia chilena Drake & Hussey, 1955 (Veliidae), Limnocoris dubiosus Montandon, 1898 (Naucoridae), Nerthra (Nerthra) parvula (Signoret, 1863), N. (N.) undosa Nieser & Chen, 1992, N. (Rhinodermacoris) praecipua Todd, 1957 (Gelastocoridae), and Sigara (Tropocorixa) termasensis (Hungerford, 1928a) (Corixidae) are endemic to the country. To this list, we add †Nerthra (Nerthra) subantarctica Faúndez & Ashworth, 2015, even though the species is only known from a subfossil. We can also inform that while water bugs are found in the archipelagoes of southern Chile, no species has been reported from the Juan Fernandez Islands, Easter Island and other off-shore islands. Several of the Chilean species are without any close extant relatives, such as C. usingeri and Aquarius chilensis (Berg, 1881) (Gerridae), or with relatives in Oceania (N. praecipua), suggesting that historical events such as dispersal and extinction have had a major influence on the composition of the Chilean fauna.

Made available in DSpace on 2021-06-25T15:05:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01. Added 1 bitstream(s) on 2021-07-15T14:36:46Z : No. of bitstreams: 1 S0085-56262021000100213.pdf: 14373775 bytes, checksum: a46eb40082682d60d8b3ae3149ec85ef (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) The subfamily Veliinae (Heteroptera: Gerromorpha: Veliidae) includes ten genera worldwide, seven of which are endemic to the American continent. Here, we provide a revision of Platyvelia Polhemus and Polhemus, 1993, which is distributed from the United States to northern Argentina, and included nine valid species prior to this study. Six species are redescribed, the synonymies of P. egregia (Drake and Harris, 1935) and P. verdica (Drake, 1951) with P. brachialis (Stal, 1860) are proposed, a lectotype is designated for P. annulipes, and two species groups are erected based on male characters: the P. annulipes group and the P. brachialis group. Keys to the species groups and species within each group, photos, and distribution maps are also included. Fundacao Oswald Cruz, Lab Brodiversidade Entomol, Inst Oswald Cruz, Rio De Janeiro, RJ, Brazil Univ Estadual Paulista, Dept Ciencias Biol, Assis, SP, Brazil Univ Sao Paulo, Dept Ciencias Biol, Ribeirao Preto, SP, Brazil Nat Hist Museum Wien, Vienna, Austria Univ Estadual Paulista, Dept Ciencias Biol, Assis, SP, Brazil FAPESP: CFBF: 2013/16367-0 FAPESP: 2015/094912 CNPq: FFFM: 301942/20196 FAPERJ: FFFM: E26/203.207/2017 FAPERJ: HDDR: E26/202.437/2019

The fauna of semiaquatic bugs (Insecta: Hemiptera: Heteroptera: Gerromorpha) from Panama has been explored mainly between the end of the 19th century and the first half of the 20th century, with few reports since then, whereas that from Colombia has been intensively studied in the last decade. Here, we describe Rhagovelia joceliae Rodrigues & Moreira, sp. nov. (Veliidae: Rhagoveliinae), from Panama. Additionally, new records from these countries are presented for Mesovelia mulsanti White, 1879, Mes. zeteki Harris & Drake, 1941 (Mesoveliidae: Mesoveliinae), Lipogomphus leucostictus (Champion, 1898) (Hebridae: Hebrinae), Hydrometra caraiba Guérin-Méneville, 1857 (Hydrometridae: Hydrometrinae), Platyvelia brachialis (Stål, 1860), Stridulivelia (Stridulivelia) raspa (Hungerford, 1929) (Veliidae: Veliinae), R. elegans Uhler, 1894, R. perija Polhemus, 1997, R. rosensis Padilla-Gil, 2011 (Veliidae: Rhagoveliinae), Euvelia advena Drake, 1957, Microvelia albonotata Champion, 1898, Mi. fantastika Padilla-Gil, 2019, Mi. mimula White, 1879 (Veliidae: Microveliinae), Metrobates laudatus Drake & Harris, 1937, Telmatometra ujhelyii Esaki, 1926 (Gerridae: Trepobatinae), Brachymetra albinervus (Amyot & Serville, 1843) (Gerridae: Charmatometrinae), Potamobates anchicaya Polhemus & Polhemus, 1995 (Gerridae: Cylindrostethinae), Limnogonus hyalinus (Fabricius, 1803), and Tachygerris opacus (Champion, 1898) (Gerridae: Gerrinae).

Hemipterans are ubiquitous in the world and a major component of global species diversity, including as important functional group in terrestrial and aquatic ecosystems. Bugs include important crop pests, vectors of human diseases, and beneficial species. The mouthparts are the best defining character for these insects, primarily adapted for plant-feeding. Nonetheless, they display a wide array of feeding strategies and food preferences. Because of the ecological diversity of hemipterans, and the microhabitats and ecosystems they occupy, no single sampling method is suitable for all groups, and it is therefore important to choose sampling methods that target the known or predicted habitat, distribution, or species interaction of a taxon. The sampling of hemipteran species can be subdivided into aquatic and terrestrial methods. We summarize sampling methods employed by hemipterists to maximize the capture of specimens, in different habitats and conditions. We describe the individual equipment commonly used, following the description of the main sampling methods by habitat types (plant-dwelling, ground-dwelling, and aquatic habitats) and methods used regardless of the habitat that they are found in. Our contribution provides a modern overview of the collection methods for the entire hemipteran order, relevant today to environmental and economic issues.

The Hemimetabola Collection of the Museum für Naturkunde Berlin, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, located in Berlin, Germany, holds types of 22 species of Triatominae (Hemiptera: Heteroptera: Reduviidae) belonging to six genera: Belminus Stål, 1859; Eratyrus Stål, 1859; Meccus Stål, 1859; Panstrongylus Berg, 1879; Rhodnius Stål, 1859; and Triatoma Laporte, 1832. We present a detailed list containing nomenclatural, taxonomic and label data, and photographs of specimens and their labels.

Stridulivelia (Aenictovelia) chocoana sp. nov. (Heteroptera: Veliidae: Veliinae) is described based on specimens from the Colombian department of Chocó. The new species is diagnosed by pronotal humeral angles, body length, male hind trochanter and paramere shape. Furthermore, we describe and illustrate the previously unknown male of Euvelia meta Molano, Moreira & Morales, 2016 (Heteroptera: Veliidae: Microveliinae) and its range is extended to Amazonas and Vichada departments.

Horvathinia pelocoroides Montandon, 1911 was described as a new genus and species based on two specimens collected in Brazil, one from Minas Gerais deposited in the Naturhistoriska Riksmuseet (Stockholm) and the other from Rio Grande do Sul deposited in the Magyar Természettudományi Múzeum (Budapest) (Montandon 1911). Subsequently, nine additional species were described based on a single specimen each, collected at different localities in southern South America: H. doellojuradoi De Carlo, 1930; H. pelleranoi De Carlo, 1930; H. castilloi De Carlo, 1938; H. meyeri De Carlo, 1938; H. bollei De Carlo, 1958; H. lenti De Carlo, 1958; H. schubarti De Carlo, 1958; H. forsteri Lauck, 1958; and H. argemii Schnack, 1972 (Schnack & Estévez 2005).

We present the results of a survey of the aquatic and semiaquatic bugs (Insecta, Hemiptera, Heteroptera) from the small streams Pechilín, Bobo, Camarón, and Macaján, located in Toluviejo Municipality, Sucre Department, Caribbean region of Colombia. Representatives of 8 families, 20 genera, and 32 species have been collected, of which 11 species are recorded for the first time from Sucre Department, 8 from the Colombian Caribbean region, and 4 from Colombia.

Gerromorpha or semiaquatic bugs have the ability to walk on the surface of the water and occupy a wide variety of habitats. They are relatively well studied in the Neotropical Region, but some species are known only from the type localities or have many gaps in their documented distributions. In this study we examined specimens housed in the National Museum of Natural History, Smithsonian Institution, and report new records for 17 species: Mesovelia bila, Hydrometra argentina, H. caraiba, H. comata, Limnobatodes paradoxus, Euvelia lata, E. mazzucconiae, Husseyella turmalis, Oiovelia cunucunumana, Paravelia conata, Platyvelia brachialis, Steinovelia virgata, Halobatopsis platensis, H. spiniventris, Ovatametra obesa, Limnogonus aduncus aduncus, and L. recurvus.

Made available in DSpace on 2020-12-10T19:48:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-28 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) The genus Steinovelia Polhemus & Polhemus, 1993 is distributed from southeastern Canada to northeastern Argentina and has been considered to contain five valid species: S. permista (Drake, 1951a), S. placida (Drake, 1951a), & stagnalis (Burmeister, 1835), S. vinnula (Drake, 1951b) and S. virgata (White, 1879a). We present here a revision of the genus with redescriptions of S. permista, S. stagnalis, S. vinnula, and S. virgata, the synonymy of S placida with S. virgata, a key, distribution maps, and photographs of all species. Fundacao Oswaldo Cruz, Inst Oswaldo Cruz, Lab Biodiversidade Entomol, Rio De Janeiro, RJ, Brazil Univ Estadual Paulista, Dept Ciencias Biol, Assis, SP, Brazil Univ Sao Paulo, Dept Ciencias Biol, Ribeirao Preto, SP, Brazil Univ Fed Alagoas, Museu Hist Nat, Maceio, AL, Brazil Univ Missouri, Div Plant Sci, Enns Entomol Museum, Columbia, MO 65211 USA Univ Estadual Paulista, Dept Ciencias Biol, Assis, SP, Brazil FAPESP: 2013/16367-0 FAPESP: 2015/09491-2 FAPESP: 2013/16654-0 FAPESP: 2015/18338-3 FAPERJ: E-26/203.207/2017 FAPERJ: E-26/200.149/2019