M. Cristina Hernández

• Doctor in Biological Science
• Fundación Para El Estudio De Especies Invasivas

In the search for specific natural enemies to control two invasive aquatic plants (IAP) from South America, Ludwigia grandiflora subsp. hexapetala (Onagraceae) and Myriophyllum aquaticum (Haloragaceae), taxonomic challenges associated with two Lysathia Bechyné, 1959 (Chrysomelidae; Alticini) species had to be resolved. Lysathia flavipes (Boheman, 1...

In the search for insects as biological control agents for the water primrose, the delphacid Pissonotus paraguayensis (Delphacidae) was found on Ludwigia grandiflora subsp. hexapetala (Onagraceae) in a wetland of Central East Argentina. The morphology of the unknown females (brachypterous and macropterous) and immature stages are described and illu...

Exotic water primroses are aggressive invaders in both aquatic and riparian ecosystems worldwide. Water primrose [Ludwigia hexapetala (Hook. & Arn.) Zardini, Gu & P. H. Raven], floating primrose-willow [Ludwigia peploides (Kunth) P. H. Raven subsp. peploides], floating primrose-willow [Ludwigia peploides (Kunth) P. H. Raven subsp. montevidensis (Sp...

The host range of the thrips Liothrips ludwigi was investigated using single- and multi-generational no-choice nymphal development and oviposition tests. Development, oviposition, and egg viability were quantified when L. ludwigi were fed three exotic Ludwigia species and seven USA native plant species. Liothrips ludwigi completed development and o...

The aim of this paper is to shed light on the boundaries of two sympatric species of Cuernavaca, C. inexacta and C. longula, to enable further ecological studies. Species in this genus are associated with water hyacinths in wetlands of Northeastern Argentina (Paraná-Paraguay waterway system) and the Peruvian Amazon. This work lists new host records...

Classical biological control –or biocontrol- is a form of pest management comprising the release of specialized natural enemies (biocontrol agents) of an exotic pest. Classical biocontrol agents are scientifically selected from among the natural enemies the pest has in its native region. However biological control is firmly resisted in many countri...

The South American water primroses, Ludwigia grandiflora (Michx.) Greuter & Burdet, L. grandiflora subsp. hexapetala (Hook. & Arn.) G.L. Nesom & Kartesz, Ludwigia peploides (Kunth) P.H. Raven, and L. p. subsp. montevidensis (Spreng.) P.H. Raven (Onagraceae, Section Oligospermum), have become invasive in several watersheds of the United States and E...

Taosa longula Remes Lenicov (Hemiptera: Dictyopharidae), a planthopper native to South America, is a candidate for the biological control of water hyacinth, Eichhornia crassipes (Mart.) Solms-Laubach (Pontederiaceae), a serious weed worldwide. Biological control requires agents that are not only specific but also effective. Damage caused by sap-suc...

ABSTRACT. „„Liothrips ludwigi (Thysanoptera: Phlaeothripidae) is described and a key to differentiate it from the other four species present in Argentina is provided. This species can be distinguished by the following characters: major setae on head and pronotum slender and brown yellowish; anteromarginal setae short (14μ-21μ), and metanotum reticu...

Abstract Descriptions of the immature stages of Taosa (Cuernavaca) longula Remes Lenicov (Hemiptera: Fulgoroidea: Dictyopharidae) and a key for their identification is provided for specimens collected on the water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach (Commelinales: Pontederiaceae), in northeastern Argentina and Peru. Newly emerged...

Taosa longula Remes Lenicov (Hemiptera: Dictyopharidae) is a planthopper from the South American tropics that feeds on water hyacinth, Eichhornia crassipes (Mart.) Solms-Laubach (Pontederiaceae). The biology of T. longula was studied in the laboratory and field to evaluate it as a potential biological control agent for this widespread aquatic weed....

Megamelus scutellaris Berg (Delphacidae) and Taosa (Cuernavaca) longula Remes Lenicov (Dictyopharidae) are specialist planthoppers that feed and reproduce on the invasive aquatic weed, Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae). They overlap geographically in several regions of South America and may, therefore, interact and compe...

Egg parasitoids (Hymenoptera: Eulophidae and Platygastridae) of Taosa (Cuernavaca) longula Remes Lenicov (Hemiptera: Dictyopharidae) are reviewed and keyed. This planthopper feeds on water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach, and was collected in Formosa, Argentina, where some of its eggs turned out to be parasitized. Two new spe...

ABSTRACT. Egg parasitoids (Hymenoptera: Eulophidae and Platygastridae) of Taosa (Cuernavaca) longula Remes Lenicov (Hemiptera: Dictyopharidae) are reviewed and keyed. This planthopper feeds on water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach, and was collected in Formosa, Argentina, where some of its eggs turned out to be parasitized. T...

Egg parasitoids (Hymenoptera: Eulophidae, Mymaridae, and Platygastridae) of Megamelus spp. (Hemiptera: Delphacidae) in Argentina are reviewed and keyed. Four new species are described: Anagrus (Anagrus) empanadus Triapitsyn, sp. nov. (Mymaridae, parasitoid of M. scutellaris Berg feeding on water hyacinth, Eichhornia crassipes (Martius) Solms-Laubac...

ABSTRACT A new species of Taosa (Hemiptera: Dictyopharidae) is described. All the stages were collected on the aquatic weed Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae) at several localities on the Paraguay River in Argentina, and in the upper Amazon River in Peru´ . Taosa (Cuernavaca) longula Remes Lenicov sp. nov. is distinguishe...

ABSTRACT. Egg parasitoids (Hymenoptera: Eulophidae, Mymaridae, and Platygastridae) of Megamelus spp. (Hemiptera: Delphacidae) in Argentina are reviewed and keyed. Four new species are described: Anagrus (Anagrus) empanadus Triapitsyn, sp. nov. (Mymaridae, parasitoid of M. scutellaris Berg feeding on water hyacinth, Eichhornia crassipes (Martius) So...

The mining flies Thrypticus truncatus Bickel & Hernández and Thrypticus sagittatus Bickel & Hernández (Diptera: Dolichopodidae) are being evaluated as biological control agents for the water hyacinth, Eichhornia crassipes (Martius) Solms-Laubach (Pontederiaceae). The behavior of adults and larvae of these species was studied in the laboratory and i...

Thrypticus truncatus is a candidate agent for biocontrol of waterhyacinth; the larvae of this diptera mine in the petioles and feed on the phloem in the vascular bundles. The mycobiota associated with T. truncatus and T. sagittatus mines was investigated during two surveys undertaken in the spring and autumn in the Delta of the Paraná River, Argent...

ABSTRACT. Larval feeding behavior of the truncatus group of Thrypticus (Diptera: Dolichopodidae) that breed in Pontederiaceae species are presented. The larvae of T. circularis Bickel & Hernández develop in globous petioles of Eichhornia crassipes (Martius) Solms- Laubach (Pontederiaceae), digging a mine near the epidermis and forming several holes...

Nine new species of Thrypticus (Diptera, Dolichopodidae) are described from South America: T. truncatus, T. sagittatus, T. yanayacu, T. circularis, T. chanophallus, T. romus, T. azuricola, T. formosensis, and T. taragui. All nine species were reared from the petioles and stems of aquatic and semiaquatic Pontederiaceae, Þve of them from water hyacin...

Introduction Water primrose, Ludwigia grandiflora (Michx.) Greuter & Burdet ssp. hexapetala (Hook. & Arn.) G.L. Nesom & Kartesz (Synonym: L. hexapetala), is an aquatic perennial creeper native to South America that invaded freshwater wetlands in California (Okada et al. 2009) and Europe. Its distribution in South America ranges from the tropics to...

Since the beginning of the investigations on natural enemies of water hyacinth, Thrypticus has been mentioned among the top seven candidates for biological control. In 1995, a revived interest for biocontrol of water hyacinth directed the investigations to new agents and Thrypticus stood as a priority candidate. Thrypticus occurs in Central and Sou...