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Simple Summary: Privets (Ligustrum spp.) are popular hedge shrubs that escape from gardens and cause negative impacts by invading forests in the United States. The narrow host specificity of the seed-feeding weevil, Ochyromera ligustri, suggests that this weevil could be considered a fortuitous biological control agent of privets. To find out the host range of this weevil, time-consuming experiments involving rearing and dissections are often conducted. Herein, we developed PCR primers to rapidly and accurately detect the presence of the weevil in privet fruits. We confirmed that the novel PCR primers specifically work for O. ligustri even with a small quantity of DNA, which was 0.01 ng. Using the newly developed PCR-based detection saves time and labor in research related to the detection and impact of this weevil. Ligustrum spp. (Oleaceae) have become invasive species in the US and negatively affect native plant diversity and richness in forests. Ochyromera ligustri (Coleoptera: Curculionidae) is considered a potential biological control agent in the US because adults feed on the foliage and larvae are seed-feeders of Ligustrum spp. To discover the relationships between O. ligustri and Ligustrum spp., fruit dissections or rearing and field observations are required. In the current research project, novel PCR primers were developed to rapidly detect the DNA of O. ligustri in molecular analyses without rearing and observation. The developed PCR primers worked even with 0.01 ng of DNA and did not amplify the DNA of the other five curculionid species tested. When the novel primers were tested with three Ligustrum spp. species common in the southeastern US, the DNA of O. ligustri was detected from all three species. We expect that the novel primers will be utilized to find out the presence and impact of O. ligustri on Ligustrum spp rapidly and accurately. [ABSTRACT FROM AUTHOR]

Air potato, Dioscorea bulbifera L. (Dioscoreaceae), is an invasive vine that climbs into vegetation outcompeting native species and altering ecosystems in the southeastern USA. The biological control agent, Lilioceris cheni Gressitt and Kimoto (Coleoptera: Chrysomelidae), has been released in Florida since 2011 and in other states including Georgia (2015), Louisiana (2016), Texas (2017), Mississippi (2018), and Alabama (2018) to manage air potato. Despite the wide distribution of the weed and mass rearing efforts, there are no studies documenting the establishment of L. cheni outside of Florida. The objectives of this study were to document the beetle release efforts by several agencies and determine the establishment and impact of L. cheni across the southeastern USA. Using community science reports and field surveys, we documented the distribution of air potato and L. cheni. Results demonstrated that the distribution of air potato extends to temperate regions from South Carolina and Georgia to subtropical regions of Louisiana, Texas, and Florida. Surveys showed that the beetle is present across all states with releases, and numbers fluctuated between 6 and 37 beetles counted per 30-surveyor-minutes. Most sites sampled had moderate to high beetle damage (scales of 3–4 out of 5), and air potato cover was low to moderate (2–3 out of 5). However, air potato was still abundant in some areas, which suggests the need for additional beetle releases and/or the use of other tactics to achieve management goals. [ABSTRACT FROM AUTHOR]

Schoenlandella Cameron, 1905 is the second largest genus of Cardiochilinae. Most members are recorded from the Old World, with a small number of species in the New World. Herein, the New World species of Schoenlandella are revised based on morphological data. This work entails a description of a new species: S. montserratensis Kang, sp. nov. and potential lepidopteran host information of the new species associated with bitter gourds on the Caribbean Island of Montserrat. Schoenlandella diaphaniae (Marsh, 1986) and S. gloriosa Mercado & Wharton, 2003 are re-described, and a key to species of New World Schoenlandella is provided. The taxonomic status of Schoenlandella is discussed. [ABSTRACT FROM AUTHOR]

The biological control agent, Cyrtobagous salviniae Calder and Sands (Coleoptera: Curculionidae) (salvinia weevil), is being used for management of the highly invasive fern Salvinia molesta Mitchell (Salvinaceae) in Louisiana and Texas, USA. The weevils and plants are transported from the nurseries and rearing facilities to the field release sites in plastic totes. Despite the increased transport of weevil-infested plants during the warmer months, limited data exist on the impact of heat stress and survivability of adult C. salviniae. Therefore, research was conducted to determine temperatures inside totes during summer transport, and to determine the upper temperature threshold for adult weevil survival. Field data demonstrated that temperatures within the totes were capable of exceeding 35 °C, and the type of lid used to secure plant material influenced internal temperature. In addition, there were no differences in temperature within the totes. Growth chamber trials determined the upper lethal time to kill 50 and 90% of the test population (ULt50 and ULt90) at 35 °C was 27.5 and 42.8 hours, respectively, while at 40 °C, the ULt50 and ULt90 was 15.0 and 25.0 hours, respectively. As the temperature increased to 50 °C, the calculated ULt50 and ULt90 values were 5.0 and 11.0 minutes, respectively. These data provided evidence that C. salviniae mortality occurs more rapidly as the temperature increases, especially > 45 °C, and that extreme temperatures can occur within transportation totes. [ABSTRACT FROM AUTHOR]

Salvinia molesta (Giant Salvinia) is a highly problematic, non-native, invasive species in the southeastern United States. Other than introduced biological control agents, observations of natural enemies to Giant Salvinia are rare within the United States. We observed a native crayfish, Procambarus clarkii (Red Swamp Crayfish), feeding on Giant Salvinia in outdoor ponds that are typically utilized for mass-rearing Cyrtobagous salviniae (Salvinia Weevil), a Giant Salvinia biological control agent. Red Swamp Crayfish consumed the roots and leaves of Giant Salvinia, which greatly reduced its biomass. To our knowledge this is the first documented observation of the Red Swamp Crayfish consuming Giant Salvinia. This observation increases our knowledge about species that can consume Giant Salvinia and is a potential new pest of concern for managers of Salvinia Weevil rearing operations. [ABSTRACT FROM AUTHOR]

A new species, Cremastobombycia chromolaenae, is described from Florida and Texas, USA. The larva is a leaf miner on Chromolaena odorata (L.) King and H. Robinson, a 2-3 m tall perennial shrub of the family Asteraceae, whose native range extends from southern Florida south to northern Argentina (Fig. 1). The plant is also known to occur in Africa, Asia, and Australia where it is considered exotic and in some countries has become a major weed. The larvae of C. chromolaenae are hypometamorphic and possess two distinct larval body forms and feeding behaviors-an early stage sap-feeding form with a flattened body and prognathous mouthparts and a later stage tissue-feeding form with a more cylindrical body and possessing hypognathous mouthparts. Based on head capsule counts and measurements, the larvae undergofive instars, with the first three instars being of the sap-feeding form and the last two tissue-feeding instars. The larval mine begins as a short, serpentine track which enlarges to a rounded, whitish, and eventually tentiform blotch. Cremastobombycia chromolaenae may have value as a biocontrol agent in those areas where the host plant has become a major problem. [ABSTRACT FROM AUTHOR]

Simple Summary: Mismatched distributions between biological control agents and their host plants occur for a variety of reasons but are often linked to climate, specifically differences in their low-temperature tolerances. How to measure and use low-temperature tolerances of control agents to inform agent prioritization, selection for redistribution, or predict efficacy is vitally important, but has not been previously synthesized in a single source. We discuss causes of climate mismatches between agents and target weeds, the traditional and non-traditional approaches that could be used to decrease the degree of mismatch and improve control, and regulatory issues to consider when taking such approaches. We also discuss the variety of cold tolerance metrics, their measurement and ecological value, and the types of modeling that can be carried out to improve predictions about potential distributions of agents. We also briefly touch on molecular bases for cold tolerance and opportunities for improving cold tolerance of agents using modern molecular tools. Many weed biological control programs suffer from large-scale spatial variation in success due to restricted distributions or abundances of agents in temperate climates. For some of the world's worst aquatic weeds, agents are established but overwintering conditions limit their survival in higher latitudes or elevations. The resulting need is for new or improved site- or region-specific biological control tools. Here, we review this challenge with a focus on low-temperature limitations of agents and propose a roadmap for improving success. Investigations across spatial scales, from global (e.g., foreign exploration), to local (selective breeding), to individual organisms (molecular modification), are discussed. A combination of traditional (foreign) and non-traditional (introduced range) exploration may lead to the discovery and development of better-adapted agent genotypes. A multivariate approach using ecologically relevant metrics to quantify and compare cold tolerance among agent populations is likely required. These data can be used to inform environmental niche modeling combined with mechanistic modeling of species' fundamental climate niches and life histories to predict where, when, and at what abundance agents will occur. Finally, synthetic and systems biology approaches in conjunction with advanced modern genomics, gene silencing and gene editing technologies may be used to identify and alter the expression of genes enhancing cold tolerance, but this technology in the context of weed biological control has not been fully explored. [ABSTRACT FROM AUTHOR]

Nymphaea mexicana Zuccarini (Nymphaeaceae) (Mexican waterlily) is an emergent floating-leaved aquatic plant from the southeastern USA that is invasive in South Africa. In invaded waterbodies this plant restricts water movement, increases siltation, decreases recreational activities, and can deplete water oxygen levels, which in turn negatively impacts aquatic fauna. Currently there are no chemical, mechanical, or biological control programs in place for N. mexicana in South Africa, but the sustainability of biological control makes this the most desirable option. Field surveys for potential biological control agents were conducted in the native range of N. mexicana in Florida, Louisiana, and Texas from Aug to Oct 2018. Leaves, stems, flowers, and roots of N. mexicana were searched for insect herbivores by hand and using Berlese funnels. Insects were prioritized for use as biological control agents by considering the extent and type of feeding damage, field host range, and incidence (percentage of sites in which each species was found). In total, 15 confirmed species were found feeding on N. mexicana, and some taxa were identified only to family level. Incidence coverage estimator mean, MMRuns, Chao 2 mean, and Chao 2 upper 95% CI species accumulation estimators predicted that between 2 and 5 species were missed during the surveys. Based on field observations, Bagous americanus LeConte (Coleoptera: Curculionidae), and Megamelus toddi Beamer (Hemiptera: Delphacidae) were prioritized. Host specificity trials will be conducted to determine whether these insects may be used as biological control agents of N. mexicana. [ABSTRACT FROM AUTHOR]