Patricio Fidalgo

Population Dynamics of Phyllocnistis citrella (Lepidoptera: Gracillariidae) and its Parasitoids in Tafí Viejo, Tucumán, Argentina

Abstract Seasonal abundance of the citrus leafminer, Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), was investigated between Nov 1999 and Apr 2003 in Tafí Viejo (Tucuman province). Phyllocnistis citrella populations increased during spring and summer, declined during fall, and disappeared in the winter. Five species of parasitoids, one exotic and four indigenous, attacked citrus leafminer immature stages in commercial and experimental lemon orchards. Ageniaspis citricola Logvinovskaya (Hymenoptera: Encyrtidae) was the most abundant parasitoid. Cirrospilus neotropicus Diez & Fidalgo (Hymenoptera: Eulophidae) was the most abundant indigenous species, followed by Galeopsomyia fausta LaSalle (Hymenoptera: Eulophidae). The other indigenous species were not common and were only occasionally collected from citrus leafminer larvae. Parasitoids and P. citrella exhibited similar population fluctuations throughout the entire sampling period. A certain degree of synchrony exists between the most abundant parasitoids (A. citricola, C. neotropicus, and G. fausta) and the pest. The highest rates of parasitism were observed in the fall. Ageniaspis citricola exhibited approximately 29.5% parasitism, whereas all the native species together were only 8.2%. Data showed that a clear dependence existed between percentages of parasitism and citrus leafminer population density for the most frequent parasitoid populations. The results of this study show that C. neotropicus has an important role among the native species present in Argentina.

Natural Distribution of Parasitoids of Larvae of the Fall Armyworm, Spodoptera frugiperda, in Argentina

Abstract To develop a better understanding of the natural distribution of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), and to update the knowledge of the incidence of its complex of parasitoids. S. frugiperda, samplings in whorl-stage corn were carried out in provinces of Argentina from 1999 to 2003. S. frugiperda larvae were collected from corn in localities of the provinces of Tucumán, Salta, Jujuy, Santiago del Estero, La Rioja, Córdoba, San Luis, Chaco and Misiones. In each locality 30 corn plants were sampled and only larvae located in those plants were collected. The parasitoids that emerged from S. frugiperda larvae were identified and counted. The abundance of the parasitoids and the parasitism rate were estimated. The S. frugiperda parasitoids collected were Campoletis grioti (Blanchard) (Hymenoptera: Ichneumonidae), Chelonus insularis (Cresson) (Hymenoptera: Braconidae), Archytas marmoratus (Townsend) (Diptera Tachinidae) and/or A. incertus (Macquart), Ophion sp. (Hymenoptera: Ichneumonidae), Euplectrus platyhypenae Howard (Hymenoptera: Eulophidae), and Incamyia chilensis (Aldrich) (Diptera Tachinidae). C. grioti was the most abundant and frequent during the five-year survey. Similar diversity of parasitoids was obtained in all the provinces, with the exception of I. chilensis and E. platyhypenae that were recovered only in the province of Salta. In the Northwestern region, in Tucumán, C. grioti and species of Archytas were the most abundant and frequent parasitoids. On the contrary, in Salta and Jujuy Ch. insularis was the parasitoid most abundant and frequently recovered. The parasitism rate obtained in Tucumán, Salta and Jujuy provinces were 21.96%, 17.87% and 6.63% respectively with an average of 18.93%. These results demonstrate that hymenopteran and dipteran parasitoids of S. frugiperda occurred differentially throughout the Argentinian provinces and played an important role on the natural control of the S. frugiperda larval population.

Systematics of the South American genus Plumarius Philippi, 1873, with descriptions of new species (Hymenoptera, Plumariidae)

ABSTRACT This contribution presents the study of a first group of species of Plumarius Philippi, 1873, as the result of an extensive survey of the morphological variation present in males. The survey uncovered many useful characters to distinguish between the numerous species of the genus. The studied group consists of Plumarius hirticornis (André, 1909) and the following four new species: Plumarius willinki Fidalgo n. sp., Plumarius filipalpis Roig-Alsina n. sp., Plumarius spiniferus Roig-Alsina n. sp. and Plumarius gradifrons Diez n. sp. A characterisation of the group, descriptions and illustrations are provided. A lectotype is designated for Konowiella hirticornis André, 1909.

Control biológico de Ctenarytaina eucalypti (Hem.: Psyllidae), plaga del eucalipto en Argentina

El objetivo de la presente nota tecnica es registrar la presencia en Argentina del parasitoide Psyllaephagus pilosus Noyes (Hym.: Encyrtidae), enemigo natural especifico de una plaga de los eucaliptos recientemente introducida, Ctenarytaina eucalypti (Maskell) (Hemiptera: Psyllidae). Ambas especies son originarias de Australia e ingresaron accidentalmente en nuestro pais. Se mencionan caracteristicas importantes tanto de la plaga como de su agente de control y se brinda la bibliografia mas importante relacionada con el tema.

Two new species of Bradynobaenus Spinola, 1851 (Hymenoptera: Bradynobaenidae) in the semiarid area of Argentina

Bradynobaenus diminutus Torréns & Fidalgo, sp. nov. and B. porteri Torréns & Fidalgo, sp. nov. (Argentina: La Rioja) are described and illustrated. A revised key of the genus is provided.

Biology and phylogenetic placement of a new species of Lasiokapala Ashmead from Argentina (Hymenoptera: Eucharitidae)

Within the ant‐parasitic wasp family Eucharitidae (Hymenoptera), the Kapala clade is a monophyletic group attacking Ectatomminae and Ponerinae. Members often express extreme phenotypic features, especially in the morphology of the paired frenal spines. Although the means of attack and developmental history of the eucharitid wasps within the ant nest are very similar, the means by which they oviposit and optimize encounters of their active first‐instar larvae with ants is highly variable. The relationships and life‐history strategies of Lasiokapala Ashmead (Hymenoptera: Eucharitidae) and related taxa within the Kapala clade are discussed based on phylogenetic analyses of morphological and molecular data. Descriptions are provided for the adults (both sexes), eggs and planidia of Lasiokapala spiralicornis sp.n. from Santiago del Estero (Argentina). Females deposit their eggs on the underside of leaves of Sida cordifolia L. (Malvaceae) and the likely host is postulated to be the genus Ectatomma (Formicidae: Ectatomminae). Even within a closely related group of genera, there is extreme independent divergence in morphology of scutellar spines, antennae and other features, but the larvae and larval biology are highly conserved across a much larger group of Eucharitidae.

Review of the genus Eotilla Schuster, 1949 (Hymenoptera: Bradynobaenidae: Typhoctinae: Eotillini) and description of new species from Argentina.

Diagnoses for the genus Eotilla Schuster, 1949 based on males and females, new generic and specific characters, descriptions of two new Argentinian species (Eotilla schusteri Torréns, Fidalgo, Roig-Alsina & Brothers, sp. nov. and E. medanito Torréns, Fidalgo, Roig-Alsina & Brothers, sp. nov., based on both sexes), a description of the female of E. superba Brothers, 1974 and redescriptions of the males of E. mickeli Schuster, 1949 and E. superba are provided. A key to the species of Eotilla is presented.

A new species of Elasmus (Hymenoptera: Eulophidae), parasitoid of Phyllocnistis citrella stainton (Lepidoptera: Gracillariidae) in south America

ABSTRACT A complex of native parasitoids has been found to attack the citrus leafminer, Phyllocnistis citrella Stainton, since its introduction into Argentina. Elasmus phyllocnistoides n. sp., an indigenous parasitoid, that achieves parasitism levels of 0.08% to 37.7%, is described, the main morphological characters of both sexes are illustrated, and characters are given to distinguish it from other Elasmus spp. present in the Neotropical region.