Nora Cabrera

Platybrotica misionensis a New Genus and Species of Luperini (Coleoptera: Chrysomelidae: Galerucinae) from Argentina

Abstract A new genus and species of Galerucinae, Platybrotica misionensis, is described from northeast Argentina (Misiones Province). This monotypic genus is characterized by the antennomeres 6–10 ventrally excavated, genal space equal to one-fourth to less than one-half of maximum ocular diameter, elytra with 2 posthumeral costae, and internal sac of aedeagus with 5 sclerites, and is assigned to the Diabroticites, a section of the subtribe Diabroticina, tribe Luperini. Adults have been found associated with wild and cultivated Cucurbitaceae.

Systena nitentula (Coleoptera: Chrysomelidae), a Flea Beetle Injurious to Alternanthera philoxeroides (Amaranthaceae): Redescription, Biology, and Distribution

Abstract Flea beetles of alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae), were collected in Argentina, Uruguay, Paraguay, and Brazil. Species in the genera Disonycha Chevrolat, Agasicles Jacoby, and Systena Chevrolat were frequently found on this weed. Systena nitentula Bechyné 1954 was the most abundant within Systena. This species is reported for the first time from Argentina at north of 30° S. The male is described and holotype female is redescribed adding new diagnostic characters: mouthparts, hind wings, metendosternite, and male and female genitalia. S. nitentula is recognized by the combined characters of piceous elytra with J-shaped vittae, a small spermatheca pump, and internal median lobe sac with five sclerotized plates. Differences in color patterns between S. nitentula, S. tenuis Bechyné, and S. s-littera L. also are considered. S. nintentula presents three instars that can be separated through head width. New biological data based on laboratory rearing and field observations shows that S. nintentula could be a monophagous species strongly associated to the alligator weed growing in terrestrial conditions. This information promotes S. nintentula as a potential biocontrol agent of this invasive weed.

Comparative Morphology of Mouthparts in Species of the Genus Acalymma Barber (Coleoptera, Chrysomelidae, Galerucinae)

Abstract The genus Acalymma Barber comprises 72 species widely distributed in America, mainly in the neotropical region. The taxonomy of this genus is in a confused state because of the superficial similarity of all species, which posses similar color patterns and elytral punctation. The significance of mouthpart characters for assessing phylogenetic relationships among subfamilies of Chrysomelidae, and especially the Alticinae and Galerucinae, has been noted by various authors. The present paper is a comparative morphological study of mouthparts based on 14 species of Acalymma. As a result of this study, the taxonomic value of the mouthparts for recognizing species is established.

Insecticidal activity of young and mature leaves essential oil from Eucalyptus globulus Labill. against Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae)

The confused flour beetle, Tribolium confusum Jaquelin Du Val, 1868, is a common pest insect known for attacking and infesting stored flour and grain. Biodegradable and ecologically natural products such as essential oils are emerging candidates for replacement of usually applied chemical pesticides. This work reported the chemical composition and effects caused by young and mature leaves essential oils (EOs) from Eucalyptus globulus Labill. against T. confusum. For both oils, no significant differences between yields were observed, being 1,8-cineole the main common constituent. Mature leaves extracts were rich in oxygenated mono- and sesquiterpenes, whereas young leaves showed greater content of non-oxygenated compounds. Bioassay was performed using EOs and 1,8-cineole solutions at different concentrations and time intervals. Adult mortality increased according to concentration and exposure time; young leaves extracts exhibited the greater effectiveness, highest mortalities (31.67%) at the minor time (2 h). At the lowest concentrations, 1,8-cineole solutions and mature leaves EOs did not achieve 100% mortality even when the bioassay was concluded (12 h), while at major doses no insects were alive. These results suggested that young and mature EOs from E. globulus constitute an alternative natural product to the control of T. confusum, since young leaves extracts, rich in monoterpene and sesquiterpene hydrocarbons, may be potential eligible candidates considering their noticeable insecticidal effects at low applied concentrations and short times of exposure.

Diabrotica calchaqui, a new species of Luperini (Coleoptera: Chrysomelidae: Galerucinae), from Argentina

Abstract The new species Diabrotica calchaqui Cabrera & Cabrera Walsh is described and illustrated based on specimens collected from Cachi, Salta Province, Argentina. This new species is assigned to the Diabrotica virgifera group, subtribe Diabroticina, tribe Luperini. D. calchaqui is recognized by the combined characters of elytra green with yellow vittae in some specimens reduced to two or three spots, humeral plicae subparallel, elytral sulcus sometimes obsolete, and internal sac of median lobe with five sclerites. Differences between D. calchaqui with Diabrotica porracea Harold, Diabrotica tumidicornis Erichson, Diabrotica mapiriensis Krysan & Smith, and Diabrotica fulvofasciata Jacoby, of similar morphology, also are discussed. Adults have been found associated with cultivated Cucurbitaceae and wild Asteraceae flowers.

A comprehensive guide to the Argentinian case-bearer beetle fauna (Coleoptera, Chrysomelidae, Camptosomata)

Abstract Knowledge of Argentinian Camptosomata has largely remained static for the last 60 years since the last publication by Francisco de Asis Monrós in the 1950’s. One hundred and ninety Camptosomata species (182 Cryptocephalinae and 8 Lamprosomatinae) in 31 genera are recorded herein from Argentina. Illustrated diagnostic keys to the subfamilies, tribes, subtribes and genera of Argentinian Camptosomata, plus species checklists and illustrations for all genera of camptosomatan beetles cited for each political region of Argentina are provided. General notes on the taxonomy and distribution, as well as basic statistics, are also included. This study provides basic information about the Camptosomata fauna in Argentina that will facilitate in the accurate generic-level identification of this group and aid subsequent taxonomic revisions, and phylogenetic, ecological, and biogeographic studies. This information will also facilitate faunistic comparisons between neighboring countries. Two nomenclatural acts are proposed: Temnodachrys (Temnodachrys) argentina (Guérin, 1952), comb. n., and Metallactus bivitticollis (Jacoby, 1907), comb. n. The following are new records for Argentina: Stegnocephala xanthopyga (Suffrian, 1863) and Lamprosoma azureum Germar, 1824. Currently, the most diverse camptosomate tribe in Argentina is Clytrini, with almost twice the number of species of Cryptocephalini. New records for Argentina are predicted.

Colaspis caligula , a new species found in association with Vitis vinifera (L.) crops in Argentina (Coleoptera: Chrysomelidae)

Some species of Colaspis Fabricius are well-known pests of several crops in Argentina. In this contribution, we describe a new species within this genus: Colaspis caligula n. sp., found in association with Vitis vinifera (Linnaeus) crops. We provide descriptions and illustrations of the mature larva, pupa and adult, as well as notes on its diagnostic characters, life cycle, and the damages produced to the plants.

Morphology of juvenile stages of Kuschelina bergi (Harold) with biological information (Coleoptera, Chrysomelidae, Alticini).

Abstract Kuschelina bergi (Harold, 1881) is being studied to be evaluated as a natural enemy of Phyla nodiflora var. minor (Hook.) N. O’Leary & Múlgura (Verbenaceae), an invasive weed in Australia. Eggs, and 1st and 3rd instar larvae are described and illustrated for the first time. The following characters distinguish Kuschelina bergi: presence of two medial setae in prosternum, mesosternum and metasternum, absence of tubercle on sternum I and eight setae in abdominal segment IX. The 3rd instar larvae of Kuschelina bergi resemble Kuschelina gibbitarsa (Say) larvae: the body shape and details of mouthparts are similar, but the morphology of the mandible is different, as is the tarsungulus which has a single seta. Differences between Kuschelina bergi and other known larvae of Oedionychina are discussed. New biological data based on laboratory rearing and field observation are also presented and discussed.

Catalog of the Types of Tenebrionidae and Perimylopidae (Insecta, Coleoptera) Deposited at Museo de La Plata (Argentina)

ABSTRACT The 224 types of species of Tenebrionidae and Perimylopidae (Coleoptera) housed in the collection of the Entomology Department of Museo de La Plata up until December 2008 were examined and listed; 96 names are recorded, 39 of them (41 percent) are represented by name bearing types (“primary” types). These 224 types belong to 85 species and 9 subespecies of Tenebrionidae assigned to the following subfamilies: Diaperinae (3 species, 3 types), Lagriinae (4 species, 9 types), Pimeliinae (53 species, 1 subspecies, 128 types), Stenochiinae (7 species, 10 types) and Tenebrioninae (18 species, 8 subspecies, 72 types), and 2 types belonging to 2 species of Perimylopidae. Species and subespecies herein treated were described by Berg (23), Burmeister (1), Bruch (1), Fairmaire (8), Flores & Carrara (1), Flores & Roig-Juñent (1), Flores & Vidal (2), Freude (2), Kulzer (27), Molinari (7), Müller (2), Peña (14), Peña & Barría (2), Pic (3), Steinheil (1) and Viana (1). Complete information is given for each type, including reference to original description, and label data. Two lists were added in order to support future research: one for specimens labelled as types but not found in the bibliography and seemingly not published and another for specimens labelled as types but not included in the original series.

Systena silvestrii Bechyné (Coleoptera: Chrysomelidae): redescription, new distribution and adult host records.

Abstract The flea beetle Systena silvestrii Bechyné 1957 was studied in context with the evaluation of natural enemies of the alligator weed, Alternanthera philoxeroides (Martius) Grisebach (Amaranthaceae). The female is described and the holotype male is redescribed adding new diagnostic characters: mouthparts, hind wings, metendosternite, male and female genitalia. Differences in color patterns between S. silvestrii, S. marcapatensis Bechyné, S. scurra scurra Scherer and S. scurra ajonjoli Bechyné Bechyné are considered. This flea beetle was collected mostly on alligator weed but also on Phyla canescens (Vebenaceae), in Argentina, Uruguay, Paraguay and Brazil. Therefore, further evaluation is strongly recommended prior to its consideration for biocontrol of A. philoxeroides.