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The lipid mediators platelet-activating factor (PAF) and lysophosphatidylcholine (LPC) play relevant pathophysiological roles in Trypanosoma cruzi infection. Several species of LPC, including C18:1 LPC, which mimics the effects of PAF, are synthesized by T. cruzi. The present study identified a receptor in T. cruzi, which was predicted to bind to PAF, and found it to be homologous to members of the progestin and adiponectin family of receptors (PAQRs). We constructed a three-dimensional model of the T. cruzi PAQR (TcPAQR) and performed molecular docking to predict the interactions of the TcPAQR model with C16:0 PAF and C18:1 LPC. We knocked out T. cruzi PAQR (TcPAQR) gene and confirmed the identity of the expressed protein through immunoblotting and immunofluorescence assays using an anti-human PAQR antibody. Wild-type (WT) and knockout (KO) parasites were also used to investigate the in vitro cell differentiation and interactions with peritoneal mouse macrophages; TcPAQR KO parasites were unable to react to C16:0 PAF or C18:1 LPC. Our data are highly suggestive that PAF and LPC act through TcPAQR in T. cruzi, triggering its cellular differentiation and ability to infect macrophages.

As we approach the end of the antibiotic era, newer therapeutic options, such as antimicrobial peptides (AMPs), are in urgent demand. AMP surface grafting onto biomaterials has been described as a good strategy to overcome problems associated with their in vivo stability. Helicobacter pylori is among the bacteria that pose greatest threat to human health, being MSI-78A one of the few bactericidal AMPs against this bacterium. Here, we report that MSI-78A grafted onto model surfaces (Self-Assembled Monolayers –SAMs), in a concentration of 30.3 ± 1.2 ng/cm2 determined by quartz crystal microbalance with dissipation (QCM-D), was able to kill, by contact, 98% of planktonic H. pylori in only 2 h. This fact was not verified against the control bacteria (Staphylococcus epidermidis), although the minimal inhibitory concentration (MIC) of MSI-78A in solution is much lower for S. epidermidis (2 µg/mL) than for H. pylori (64 µg/mL). Our results also demonstrated that, in opposite to other bacteria, H. pylori cells were attracted to ethylene glycol terminated (antiadhesive) surfaces, which can explain the high bactericidal potential of grafted MSI-78A. This proof of concept study establishes the foundations for development of MSI-78A grafted nanoparticles for gastric infection management within a targeted nanomedicine concept. This article is a result of the project NORTE-01-0145-FEDER-00012, (NORTE 2020) and FCT/MCTES-through the UID/BIM/04293/2019, PTDC/CTM-BIO/4043/2014, UID/QUI/50006/2013 (LAQV-REQUIMTE) projects. Claudia Monteiro acknowledges FCT for the SFRH/BPD/79439/2011 grant.

International audience; Persistent Helicobacter pylori (H. pylori) infection is related to 90% of gastric cancers. With bacterial resistance rising and treatment inefficiency affecting 15% of the patients, alternative treatments urge. Chitosan microspheres (ChMics) have been proposed as an H. pylori-binding system. This work evaluates ChMics biocompatibility, mucopenetration and capacity to treat H. pylori infection in mice after oral administration. ChMics of different size (XL, ∼120 µm and XS, ∼40 µm) and degree of acetylation (6% and 16%) were developed and revealed to be able to adhere both human and mouse-adapted H. pylori strains without cytotoxicity towards human gastric cells. Ex vivo studies showed that smaller (XS) microspheres penetrate further within the gastric foveolae, suggesting their ability to reach deeply adherent bacteria. In vivo assays showed 88% reduction of infection when H. pylori-infected mice (C57BL/6) were treated with more mucoadhesive XL6 and XS6 ChMics. Overall, ChMics clearly demonstrate ability to reduce H. pylori gastric infection in mice, with chitosan degree of acetylation being a dominant factor over microspheres' size on H. pylori removal efficiency. These results evidence the strong potential of this strategy as an antibiotic-free approach to fight H. pylori infection, where microspheres are orally administered, bind H. pylori in the stomach, and remove them through the gastrointestinal tract. STATEMENT OF SIGNIFICANCE: Approximately 90% of gastric cancers are caused by the carcinogenic agent Helicobacter pylori, which infects >50% of the world population. Bacterial resistance, reduced antibiotic bioavailability, and the intricate distribution of bacteria in mucus and within gastric foveolae hamper the success of most strategies to fight H. pylori. We demonstrate that an antibiotic-free therapy based on bare chitosan microspheres that bind and remove H. pylori from stomach can achieve 88% reduction of infection from H. pylori-infected mice. Changing size and mucoadhesive properties, microspheres can reach different areas of gastric mucosa: smaller and less mucoadhesive can penetrate deeper into the foveolae. This promising, simple and inexpensive strategy paves the way for a faster bench-to-bedside transition, therefore holding great potential for clinical application.

We would like to thank Herminia de Lencastre (ITQB-AX NOVA), Adriano Henriques (ITQB-AX NOVA) and PaulaTamagnini (i3S) for the gift of chromosomal DNA, Paulo Tavares (I2BC-CNRS) and Adriano Henriques for the gift of flagellin and anti-sigmaA antibodies, respectively, and Diogo Pereira for carrying out some growth kinetic assays. This work was supported by the FundacAo para a Ciencia e a Tecnologia [Grant Numbers PTDC/BIA-MIC/30696/2017 to ISN and UID/Multi/04378/2019 to Unidade de Ciencias Biomoleculares Aplicadas UCIBIO; and fellowship PD/BD/105737/2014 to F.L.]. ATP-binding cassette (ABC) type I importers are widespread in bacteria and play a crucial role in its survival and pathogenesis. They share the same modular architecture comprising two intracellular nucleotide-binding domains (NBDs), two transmembrane domains (TMDs) and a substrate-binding protein. The NBDs bind and hydrolyze ATP, thereby generating conformational changes that are coupled to the TMDs and lead to substrate translocation. A group of multitask NBDs that are able to serve as the cellular motor for multiple sugar importers was recently discovered. To understand why some ABC importers share energy-coupling components, we used the MsmX ATPase from Bacillus subtilis as a model for biological and structural studies. Here we report the first examples of functional hybrid interspecies ABC type I importers in which the NBDs could be exchanged. Furthermore, the first crystal structure of an assigned multitask NBD provides a framework to understand the molecular basis of the broader specificity of interaction with the TMDs. publishersversion published

A new species of Bessierus Thomas & Orth, formerly a monotypic genus, is described from Amapá State, Brazil. The type species of the genus, B. doloris Thomas & Orth, had only its nymphs described until recently, when its male imago was associated to nymphs mainly based on pigmentation pattern. Bessierus riobranco sp. n. here described has no significant difference on pigmentation pattern from B. doloris, thus the new species could be the male imago of B. doloris, and the putative imago of B. doloris a new species, or even both described imagoes could be new species. Still, a new male imago existence cannot be neglected and we opted to provide a properly description, diagnosis and illustration, hence contributing to the knowledge of mayfly neotropical diversity and future research on the genus. The generic concept of Bessierus and its type species diagnoses are altered to accommodate the new species, and a new record of B. doloris is provided.

Three unusual nymphs of Euthyplociidae, subfamily Euthyplociinae, are described from Ecuador. A new genus and new species are established to accommodate these individuals. The morphologically unique specimens are defined by the following characters: short, stout tusks lacking spine-like setae but densely covered with long, hair-like setae; head almost as long as wide; long, quadrate clypeus with acute apicolateral projections; apex of 3rd segment of labial palp acute; apex of 3rd segment of maxillary palp acute and narrow. The hind wing is small, similar to that of Mesoplocia. An ongoing study of the phylogeny of the family recovers Dasyplocia gen. nov. as closely related to Euthyplocia and Mesoplocia.

Helicobacter pylori infection is one of the major risk factors for gastric cancer development. Available antibiotic-based treatments not only fail in around 20% of patients but also have a severe negative impact on the gut microbiota. Recently, we demonstrated that nanostructured lipid carriers (NLC), even without any drug loaded, are bactericidal against H. pylori at low concentrations. This work aims to clarify NLC mode of action and to evaluate if their bactericidal effect is specific to H. pylori without affecting bacteria from microbiota. NLC were produced by hot homogenization followed by ultrasonication method, using Precirol®ATO5 and Miglyol®812 as lipids and Tween®60 as a surfactant. NLC were able to eradicate H. pylori without affecting the other tested bacteria (Lactobacillus, E. coli, S. epidermidis and S. aureus). Bioimaging assays demonstrated that NLC rapidly bind to and cross the H. pylori bacterial membrane, destabilizing and disrupting it, which leads to leakage of the cytoplasmic contents and consequent bacterial death. In an era where efficient alternatives to antibiotics are urgent, NLC are an interesting route to be explored in the quest for new antibiotic-free therapies to fight H. pylori infection.

SUMMARYThe speciesPhytomonas serpensis known to express some molecules displaying similarity to those described in trypanosomatids pathogenic to humans, such as peptidases fromTrypanosoma cruzi(cruzipain) andLeishmaniaspp. (gp63). In this work, a population ofP. serpensresistant to the calpain inhibitor MDL28170 at 70µm(MDLRpopulation) was selected by culturing promastigotes in increasing concentrations of the drug. The only relevant ultrastructural difference between wild-type (WT) and MDLRpromastigotes was the presence of microvesicles within the flagellar pocket of the latter. MDLRpopulation also showed an increased reactivity to anti-cruzipain antibody as well as a higher papain-like proteolytic activity, while the expression of calpain-like molecules cross-reactive to anti-Dm-calpain (fromDrosophila melanogaster) antibody and calcium-dependent cysteine peptidase activity were decreased. Gp63-like molecules also presented a diminished expression in MDLRpopulation, which is probably correlated to the reduction in the parasite adhesion to the salivary glands of the insect vectorOncopeltus fasciatus. A lower accumulation of Rhodamine 123 was detected in MDLRcells when compared with the WT population, a phenotype that was reversed when MDLRcells were treated with cyclosporin A and verapamil. Collectively, our results may help in the understanding of the roles of calpain inhibitors in trypanosomatids.

Silicone rubber (SR) peritoneal dialysis (PD) catheters are prone to bacterial adhesion and biofilm formation, which contributes to development of infection and associated morbidity in PD patients. We herein evaluate whether surface immobilization of graphene nanoplatelets (GNP) provides antimicrobial properties to SR. Dip and spray coating were used to deposit a dispersion containing SR and GNP-M5 or its oxidized form (GNP-M5ox) on the surface of silicone. The antimicrobial effect of GNP exposure and oxidation towards Staphylococcus epidermidis was assessed. GNP was successfully exposed on the surface, and while dipping provided better adhesion of either GNP, spraying resulted in uniform and higher surface coverage. Spraying led to enhanced bacterial adhesion comparing to dip coated and uncoated SR, which are similar. However, independently of the technique, GNP-M5ox coatings induced higher bacterial death. As such, SR/GNP-M5ox coating performed by dipping revealed to be the most promising approach, preserving bacterial adhesion levels of silicone while increasing bacterial death to around 80%. For the first time, graphene-based materials antimicrobial activity was evaluated by quantification of bacterial adhesion and viability. The high antibacterial effect, associated with a stable and cytocompatible coating which does not delaminate from SR surface, demonstrates its potential use in silicone biomedical industry. (c) 2018 Elsevier Ltd

Despite its wide, almost worldwide distribution, the mayfly genusCloeonLeach, 1815 (Ephemeroptera: Baetidae) is restricted in the Western hemisphere to North America, where a single species is reported. In the Neotropics, except for some species wrongly attributed to the genus in the past, there are no records ofCloeon. Recently, however, specimens of trueCloeonwere collected along the coast of Espírito Santo, Southeastern Brazil. In order to verify the hypothesis that this species was recently introduced to Brazil, our aim was to identify the species based on morphological and molecular characters and to confirm the presence of true representatives of the genus in the Neotropics. Our results revealed that the specimens found in Brazil belong to the Afrotropical species C. smaeleniLestage, 1924. The identity of the species, its distribution, along with its previous absence in regularly sampled sites, is a clear sign that the specimens ofC. smaelenifound in Espírito Santo are introduced, well established, and that the colonization took place very recently.

Polyplocia nebulosa sp. nov. is described based on male and female imagos from Malaysia, Sabah State. Nymphs provisionally assigned to this species are also described. This species can be readily separated from P. vitalisi by the color pattern of the wings, with light brown longitudinal veins, narrow dark brown clouds on cross veins and margins of wings tinged with brown. The male genitalia are distinct from those of other species of Polyplocia : penes are broad, T-shaped, with large lateral projecting lobes, which are apically rounded, and with a small dorsolateral spine on each lobe; the styliger plate is short and not projected posteriorly. Eggs of the genus are described for the first time using scanning electron microscopy. Eggs are 265–267 µ m in length, 170–186 µ m in width, barrel-shaped, without polar caps or other attachment structures, with one visible micropyle and with chorion forming an irregular mesh with raised ridges (mesh between 3.8–8 µ m). A key to male adults of Polyplocia is provided and additional records of Polyplocia from Thailand are given.

An unusual species of Leptophlebiidae is described based on males, females, and nymphs from Rio de Janeiro State, Brazil. As a consequence of its distinct characteristics on all stages, a new genus is established. The new genus can be distinguished from other South American Leptophlebiid genera mostly by: Adults: vein MA of fore wings asymmetrical; hind wings with costal projection well developed, Sc ending at cross vein near costal projection; tarsal claws dissimilar, one blunt other acute; projections of styliger plate forming two well developed lobes with rounded apex, ventrally obstructing view of the penes; penes fused on basal half, each lobe with a ventral furrow and a long and slender spine directed anteriorly. Nymphs: Head prognathous, wider than labrum; labrum with prominent median emargination, with three subtle crenulations; body flattened; hind wings pads present; tarsal claws with over 20 denticles, subapical denticle much larger than remaining denticles; gills long and narrow, present on abdominal segments I–VII; posterolateral projections present on abdominal segments VIII–IX. Phylogenetic analyses conducted based on a previously published data matrix that included other South America leptophlebiid genera placed Poranga nessimiani gen. nov. et sp. nov. as sister to Bessierus + Perissophlebioides. In most analyses this clade was recovered within the Farrodes complex. Nymphs of the new taxa are particularly similar to Bessierus, whereas adults share the very acute costal projection on hind wings seen in non-dipterous members of the Farrodes complex.

Helicobacter pylori (H. pylori) is one of the most common infectious agents in the world and it is thought to colonize the gastric mucosa of about half of the world's population causing several gastric diseases. In this work, the effect of surface chemistry on H. pylori nonspecific adhesion, viability, and morphology was evaluated using three H. pylori strains with different adhesins expression profile. Self-assembled monolayers (SAMs) of alkanethiols on gold were used to obtain surfaces exposing different functional groups: OH, CH3, and ethylene glycol (EG4). Bacterial adhesion onto the surfaces reached a plateau at 2 h. There was a correlation between adhesion and the exposed surface group, with bacterial cells adhering preferentially to CH3-SAMs while EG4-SAMs prevented H. pylori adhesion during the entire adhesion test (24 h). Surfaces that presented the EG4 group were also the only ones that significantly reduced the viability of adhered bacteria. Surface chemistry also influenced the morphology of adhered bacteria. The H. pylori rod shape observed in the control (Tissue Culture Polyethylene—TCPE) was only retrieved on CH3-SAMs. This work demonstrates that surface chemistry, namely specific functional groups on the material, influence the nonspecific adsorption of H. pylori. Moreover, the features of the bacterial strain and the surface chemistry can alter the adhesion kinetics, as well as the morphology and viability of attached bacteria. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.

Gastric cancer is the third leading cause of cancer related deaths worldwide and Helicobacter pylori ( H. pylori ) persistent infection has been pointed as a causative agent of this disease. Current antibiotic based treatments to eradicate this bacterium fail in 20% of the patients, potentially leaving 140 million people in the world without alternative therapy. It is herein proposed the use of azide–alkyne coupling (“click chemistry”) to produce glycan-coated mucoadhesive microspheres that bind and remove the H. pylori adherent to the gastric mucosa through specific bacterial adhesin–glycan interactions. Glycan immobilization is performed via chitosan’s primary alcohol group, rather than the more reactive primary amines in order to preserve the amine groups that confer chitosan its mucoadhesiveness. It is shown that chitosan microspheres decorated with Lewis b glycans (Leb-Mic) bind specifically to H. pylori strains expressing the BabA adhesin (strains recognized as highly pathogenic) (∼230 bacteria/microsphere), are non-cytotoxic, are retained in the stomach of C57BL/6 mice for around 1.5 h. Also, these Leb-Mic are able to prevent and remove H. pylori adhesion to gastric mucosa expressing the same glycan, in tissue sections from mice and human gastric mucosa ( in vitro ) and in fresh mice stomachs ( ex vivo ). These results provide proof-of-concept on the potential of glycan-decorated microspheres as an innovative therapeutic strategy against H. pylori and highlight the prospective of using targeted biomaterials to fight gastrointestinal infection. Statement of Significance Gastric cancer has been associated with persistent infection by Helicobacter pylori , a bacterium that colonizes half of world population and whose available antibiotic treatment fails in 20% of cases. H. pylori adhesion to gastric epithelium is mediated between bacterial adhesins and glycans expressed in gastric mucosa. We demonstrate that these glycans can be immobilized in a controlled orientation into mucoadhesive chitosan microspheres, making them selective for different H. pylori strains. Efficacy studies (in vitro and ex vivo) with mice and human gastric mucosa that express the same glycan, revealed microspheres capacity to remove/prevent specific H. pylori adhesion, envisaging their future application as bacteria scavenging from stomach. This bacteria-binding strategy can be extrapolated to target other cells/bacteria using suitable ligands.

Helicobacter pylori (H. pylori) colonizes the gastric mucosa of over 50% of the world population, causing several pathologies, such as gastric ulcers and gastric cancer. Since current antibiotic treatments are inefficient in 20% of cases alternative therapies are needed. This work reports the ability of chitosan microspheres to adhere to H. pylori and prevent/remove H. pylori colonization. Adhesion of H. pylori strains with different functional adhesins (BabA and/or SabA) to chitosan microspheres (diameter 167 ± 27 μm) occurs at both pH 2.6 and 6.0, but is higher at pH 6.0. Bacterial adhesion to a gastric cell line expressing sialylated carbohydrates (SabA receptors) was performed at the same pH values using H. pylori strains with and without SabA. At both pH values addition of microspheres to gastric cells before and after pre-incubation with H. pylori decreased bacterial adhesion to cells. Furthermore, the chitosan microspheres were non-cytotoxic. These findings reveal the potential of chitosan microspheres as an alternative or complementary treatment for H. pylori gastric eradication or prevention of H. pylori colonization.

Two new species of Ulmeritoides Traver, 1959 are described from Southeastern Brazil based on male and female imagos. Ulmeritoides angelus sp. nov. (Holotype male deposited in DZRJ: Minas Gerais State) differs from all other species of the genus by the following combination of characters: forewings hyaline, base dark brown and purplish; veins R1 light brown; dark brown spots on bullae of veins Sc and R2; apex of penis lobes somewhat rounded, each with one central spine. Ulmeritoides tamoio sp. nov. (Holotype male deposited in DZRJ: Sao Paulo State) differs from all other species of the genus by the following combination of characters: wings hyaline; veins C, Sc and R1 brownish; brownish spots on bullae of veins Sc and R2; apex of penis lobes straight, ending in rather acute apical and mesal projections. An updated key to the genera Ulmeritoides Traver, 1956 and Ulmeritus Traver, 1956 is also given.

Helicobacter pylori infection has been associated with several gastric diseases. This bacterium colonizes the gastric mucosa of half of the world’s population, and available treatments are unsuccessful in practically one in every five patients. Mucoadhesive polymers, such as chitosan, are being investigated as gastric drug delivery systems. However, since chitosan is also known for its antimicrobial properties, this work aims to evaluate H. pylori interactions with chitosan under simulated gastric environments, namely using various pHs (2.6, 4 and 6), pepsin and urea. To enable the visualization of adherent bacteria, ultrathin chitosan films were produced by spin-coating on gold/glass surfaces, cross-linked with genipin and characterized by Fourier transform infrared reflection absorption spectroscopy, ellipsometry and electrokinetic analysis. Films with homogeneous thickness of 11.7 ± 0.6 nm were produced, and were stable and protonated at all the pHs used. Furthermore, they adsorbed pepsin in all these pHs, in contrast to urea, of which a small adsorption was only observed at pH 6. H. pylori binding to chitosan was higher at pH 2.6 although most of adherent bacteria were dead. The presence of pepsin decreased bacterial adhesion, but increased its viability while in a more stressed morphology (coccoid form). The presence of urea did not affect the amount, morphology or viability of chitosan-adherent bacteria. In suspension, the decrease in pH changed H. pylori zeta potential from negative to positive. Moreover, bacteria were only culturable when incubated in pH 6 with and without urea (without pepsin). This work demonstrates that chitosan has the capacity to bind and kill H. pylori in a range of pHs independently of urea. This opens new perspectives for the application of chitosan-based materials to the elimination of H. pylori gastric colonization, though pepsin might appear to be an obstacle.

Physical environment of streams present many challenging factors to the organisms living under its influence. Water speed, one of the most important factors affecting such environments, has local influence on substrata, temperature, and oxygen levels. It acts determining species distributions and morphological and behavioral adaptations of organisms. The aim of this study was to assess the relative size of gills of Cloeodes jaragua on two mesohabitats: lentic environment (river dam) and lotic environment (fast flowing area of a stream) in Parque Nacional da Serra dos Órgãos (RJ, Brazil). Twenty individuals were collected on each environment and width of the head and gills were taken. Lentic environment showed nymphs with broader and more constant measurements than the lotic environment. The former, despite being composed of nymphs on different stages of development, presented individuals with narrower gills. Both, head width and environment type explained gills size, showing that streams habitat conditions are important in shaping the morphology of these animals. O ambiente físico dos rios apresenta diversos desafios para os organismos que vivem sob sua influência. A velocidade da água, um dos fatores mais importantes a atuar nesses ambientes, tem influência local no substrato, temperatura e oxigenação da água. A força da correnteza age determinando a distribuição das espécies e as adaptações morfológicas e comportamentais dos organismos. O objetivo desse estudo foi abordar o tamanho relativo das brânquias de Cloeodes jaragua em dois meso-habitats: um ambiente lêntico (represa) e um ambiente lótico (áreas de correnteza) no Parque Nacional da Serra dos Órgãos - RJ. Um total de 20 indivíduos foi coletado em cada tipo de ambiente e as larguras da cabeça e brânquias foram medidas. O ambiente lêntico apresentou ninfas com medidas mais largas e mais constantes que o ambiente lótico. Este último, apesar de ser composto por ninfas em diferentes estágios de desenvolvimento, apresentou indivíduos com menores larguras de brânquias. Ambos, largura da cabeça e tipo de ambiente, explicaram o tamanho das brânquias, mostrando as condições dos habitats dos rios como importantes modeladores da morfologia desses animais.

A new species of the mayfly genus Thraulodes Ulmer is described based on specimens from the states of Rio de Janeiro and São Paulo, Brazil. Nymph and imagos from both sexes are described. The new species can be easily recognized by abdominal and legs color pattern whether from nymphs or imagos.

Amanahyphes saguassu Salles and Molineri, 2006 is firstly recorded from state of Pará. Specimens from Pará presented wings with more curved anal veins than those from state of Amazonas, illustrated in the original description, showing variability among populations of this species. Amanahyphes saguassu is similar to Leptohyphodes inanis (Pictet, 1843), sharing both nymph and adult characteristics.

A new species of Thraulodes Ulmer, 1920 is described from Rio de Janeiro. The species resembles the recently published Thraulodespelicanus Mariano and Froehlich, 2011 (in Mariano et al. 2011) due to the length and width of the penes. However, Thraulodes bonito sp. nov. differs from this and all other species of the genus by the wide penes, the triangular shape of the styliger plate with median projection short and apex rounded, the abdominal color pattern and the presence of 1-3 weakly marked cross veins basal to bullae. The new species is described based on male imagos, female subimagos and nymphs.

A new species of the recently erected genus Tortopsis is described from males and females imagos collected in Macaé river, Rio de Janeiro State. Tortopsis canum sp. nov. can be recognized by the color pattern of the head and pronotum, strongly shaded with black in both sexes, male genitalia with parastyli long and straight and female parastyli receptor “C” shaped, with receptors large, occupying nearly all extension of sternum VIII. This new species represents the first record of the genus Tortopsis in Brazil.

Cloeodes Traver, 1938 (Ephemeroptera, Baetidae) was established to include Baetidae specimens from Puerto Rico. Of the three species described by Traver (1938), only the type-species C. maculipes remains in this genus (Domínguez et al. 2006). A revision of Cloeodes by Waltz & McCafferty (1987) redefined its distinct characteristics and revealed the genus to be a widespread group of Neotropical origin with several species from South and Central America as well as from Southwestern North America and Southeast Asia.