The way to maturity: taxonomic study on immatures of Southern Brazilian Coccinellini (Coleoptera: Coccinellidae) species important in biological control

Among the predatory ladybird beetles (Coccinellidae: Coleoptera), members of the Coccinellini, predators of aphids and psyllids, stand out. Although the beneficial status of these beetles has been acknowledged by biological control researchers, there are no keys or detailed studies on the immature stages of South American Coccinellidae, especially Coccinellini. We provide descriptions and illustrations of the immatures and adults of major predatory Coccinellini species in southern Brazil along with an identification key for fourth instar larvae and pupae. The following species are included: Cycloneda sanguinea (Linnaeus, 1763), Eriopis connexa (Germar, 1824), Harmonia axyridis (Pallas, 1773), Hippodamia convergens Guérin-Méneville, 1842 and Olla v-nigrum (Mulsant, 1866). The morphological study, which included the use of scanning electron microscopy, revealed new characters such as the type of tarsal claws, spiracles, chalazae, parascoli and strumae. The identification key provided here may be useful in biological control programs.

Predation of Brevicoryne brassicae and Aphis craccivora by Eriopis connexa depending on availability

Predator species under field conditions can face different and variable densities of prey species. This work evaluated the functional response of the neotropical lady beetle Eriopis connexa(Coleoptera: Coccinellidae) subjected to different densities of the aphids Brevicoryne brassicaeand Aphis craccivora(Hemiptera: Aphididae). Thus, predation rates were analyzed of fourth-instar larvae and one-day old adults of the lady beetle preying upon the aphids at constant densities of 20, 40, 50, 60, and 70 aphids with 15 repetitions per density. The aphids were offered on 5 cm leaf discs of each plant host. The handling times and attack rates were 0.03 h-1and 0.27 h-1for larvae and 0.03 h-1and 0.15 h-1for adults fed B. brassicae and 0.59 h-1and 0.35 h-1for larvae and 0.70 h-1and 0.95 h-1for adults fed A. craccivora, respectively. Both larva and adult lady beetles increasedpredation rate as a function of prey density offered, with an estimated maximum number of prey consumed of 30.3 and 31.6 B. brassicae and 36.3 and 34.6 of A. craccivora by larva and adult lady beetles at the highest prey density, respectively. In conclusion, larvae and adults of E. connexaexhibited a type II functional response.

Evaluation of biological parameters of Eriopis connexa (Germar, 1824) and Coleomegilla maculata (DeGeer, 1775) (Coleoptera: Coccinellidae) fed with alternative prey developed at the Integrated Center for Pest Management - UFRRJ

The aim of this work was to evaluate the potential of live larvae of Drosophila melanogaster (Meigen) (Diptera: Drosophilidae) as alternative prey used in the E. connexa and C. maculata rearings developed at the Integrated Center for Pest Management (CIMP) (UFRRJ, Seropédica campus, state of Rio de Janeiro, Brazil), in comparison to the use of flour moth eggs, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae), sterilized by ultraviolet radiation. The obtained results showed that the larvae of the two lady beetles developed adequately, as well as generating fertile adults and viable eggs when fed on live larvae of D. melanogaster, similar to E. kuehniella eggs. It can be concluded that the live larvae of this fly can replace the eggs of the flour moth in the rearing of the two lady beetles in the laboratory.

The Capacity for Limb Regeneration During Metamorphosis is Broadly Conserved in the Coccinellidae

A standardized laboratory procedure tested the limb regeneration abilities of 18 populations (16 species) of lady beetles which were then scored, relative to unoperated controls, based on survival, the proportion regenerating the limb completely or partially, and the magnitude of developmental costs (delayed development, reduced body size) associated with limb ablation. Newly molted fourth instar larvae each had a single foreleg amputated at the base of the femur. All species except Propylea dissecta (Mulsant) showed some complete limb regeneration, with limb regeneration index (LRI) scores ranging from 0.025 to 0.905 out of a possible 1.00 (mean = 0.598). Eriopis connexa Germar, an aphidophagous neotropical species, scored the highest. Widely distributed species that dominate agricultural habitats all scored above 0.75, and the only herbivore, Henosepilachna argus (Geoffroy), scored second from lowest. Prolonged pupal development was the most common cost, occurring in nine species, and correlating negatively with regeneration. Taxonomic distance between species correlated with regeneration, but explained <5% of variation; principal component analysis indicated that the LRI was the main factor distinguishing species. We infer that this capacity is conserved, not because of any adaptive advantage conferred, but because the genes responsible are normally activated during pupal development to generate the adult body plan and reconstitute appendages with direct correspondence to larval progenitors. However, good regeneration capacity was associated with the ecological success of the species. In general, broad geographic distribution, guild dominance, polyphagy, interspecific competitiveness, phenotypic flexibility, and invasiveness were characteristics generally shared by species with high levels of regeneration.

Números cromosómicos en insectos de Argentina. I. Caracterización citogenética en 15 especies de importancia económica

En el presente trabajo se informan los números cromosómicos somáticos y/o gaméticos de 15 especies de insectos presentes en Argentina, que se caracterizan por su importancia económica como plagas de cultivos o controladores de plagas agrícolas, pertenecientes a los siguientes órdenes y familias: Neuroptera, Chrysopidae: Ceraeochrysa cincta (n = 5 + XY), Ceraeochrysa paraguaria (n = 5 + XY), Chrysoperla argentina (n = 5 + XY), Chrysoperla asoralis (n = 5 + XY) , Chrysoperla externa (n = 5 + XY), Leucochrysa cruentata (n = 7 + XY) y Plesiochrysa elongata (n = 5 + XY), Coleoptera, Coccinellidae: Cycloneda sanguinea (n = 9 + XYp), Eriopis connexa (n = 9 + XYp), Harmonia axyridis (n = 7 + XYp), Hippodamia convergens (n = 9 + XYp) y Melyridae: Astylus atromaculatus (n = 8 + XYp), Dermaptera, Forficulidae: Doru lineare (2n = 20), D. luteipes (2n = 20) y Diptera, Ulidiidae: Euxesta eluta (n = 5 + XY). Por primera vez, se cita información cromosómica para seis especies, incluyendo un número cromosómico gamético adicional para Euxesta eluta. Además, se da a conocer en Astylus atromaculatus un número cromosómico diferente a los recuentos previamente reportados.