Journal of Entomological and Acarological Research

Hyperparasitic showdown: Sclerodermus cereicollis, a non-aggressive but surprisingly secondary hyperparasitoid

Serena Malabusini — 2024-05-29

This study investigates the dynamics of hyperparasitism within the Bethylidae family, focusing on the interaction between Sclerodermus cereicollis and Goniozus legneri, two parasitoid wasp species characterized by different sociality and aggressivity towards conspecifics. Experimental trials were conducted using Corcyra cephalonica larvae as hosts, with different setups to stimulate competition. The results revealed unexpected behaviors, especially by S. cereicollis, including aggressive interactions, cannibalism, and hyperparasitism. In contrast, despite the typically aggressive nature of G. legneri, no particular hostility was observed toward S. cereicollis. The study highlights the complex dynamics of competition for resources among parasitoids, shedding light on the adaptive strategies and fitness costs associated with hyperparasitism. These findings contribute to a deeper understanding of the ecological interactions within parasitoid wasp communities.

Chrysis fuscipennis or Chrysis angolensis? An answer with new synonymies, a new combination and species resurrected (Hymenoptera, Chrysididae)

Paolo Rosa — 2024-03-11

All species of the Chrysis angolensis group were synonymised with C. angolensis Radoszkovsky, 1881, excluding Chrysis diademata Mocsáry, 1889, endemic of the Philippines. However, after the study of type materials, four species are herein resurrected: Chrysis callaina Gribodo, 1884 stat. reviv., C. erratica Abeille de Perrin and du Buysson in du Buysson, 1887 stat. reviv., C. mossulensis Abeille de Perrin and du Buysson in du Buysson, 1887 stat. reviv., C. sulcifera Bischoff, 1910 stat. reviv. New synonymies are proposed for the following taxa: C. szalayana Mocsáry, 1912 n. syn. and C. ukerewensis Mocsáry, 1914, n. syn. of C. callaina Gribodo, 1884; Chrysis janthina Smith, 1874 n. syn. of C. brachyceras Bischoff, 1910. The new combination Praestochrysis brachyceras (Bischoff, 1910) n. comb. is proposed. Chrysis fuscipennis Brullé, 1846, the name in use for the oldest taxon described in the angolensis group, was replaced with Chrysis angolensis Radoszkovsky, 1881 because primary junior homonym of C. fuscipennis Dahlbom, 1829. However, Chrysis angolensis is here regarded as nomen dubium, C. fuscipennis Dahlbom, 1829 as nomen oblitum, because no longer in use as a valid name after 1899, and C. fuscipennis Brullé as nomen protectum, thus making the name C. fuscipennis Brullé, 1846 stat. reviv. available and restored.

Comparison of different trapping devices for the capture of Bactrocera oleae (Rossi) and other non-target insects in the Mediterranean basin

Andrea Sciarretta — 2024-04-05

The present study aimed to compare some commercial traps baited with ammonium carbonate for their efficacy in monitoring Bactrocera oleae (Rossi) and their selectivity toward beneficial insects, under the conditions of olive groves located in five Mediterranean countries (Greece, Italy, Lebanon, Spain, Tunisia). The selectivity of the devices was evaluated toward several groups of non-target insects, namely lacewings (Chrysopidae), hoverflies (Syrphidae), ladybirds (Coccinellidae), bees (Apoidea) and hymenopteran parasitoids. The following devices were compared: yellow sticky panel, green sticky panel, Jackson trap with different combinations of yellow and white colours of the device and/or the panel, and McPhail trap. In most cases, the McPhail trap and the yellow panel showed the highest efficacy in monitoring male and female B. oleae flies; however, the yellow panel was most attractive for some groups of non-target insects, particularly the hymenopteran parasitoids, whereas the comparative non-target effects were sitespecific for the other arthropod groups. In the case of Chrysopidae, McPhail caught more individuals than the other traps in Italy and Spain, whereas in Lebanon and Greece, the highest number of individuals was captured in the two sticky panels. Coccinellidae were found in very low numbers only in Lebanon on yellow panels. Syrphidae were captured mainly on sticky panels in Greece and Tunisia. Apoidea were found only on yellow panels in Lebanon. The choice between the McPhail trap and the yellow panel should be made on the basis of various evaluations carried out at the site, including operational ones.

Exploring biocidal effects of methyl salicylate and limonene toward Trogoderma granarium Everts

Mokhtar Abdulsattar Arif — 2024-01-29

The khapra beetle, Trogoderma granarium, poses a significant threat as a post-harvest pest in stored products and stands out as a crucial quarantine concern globally. Unlike many other stored product pests, this species proved challenging to manage using conventional insecticides and alternative non-chemical methods. The exploration of plant-based natural products, particularly essential oils, as alternatives arises in response to challenges associated with the prolonged use of synthetic insecticides. While essential oils show promising activity, their use encounters challenges associated with standardization. This study investigates the feasibility of employing some single chemical compounds widespread in several essential oils with insecticidal activity as candidate insecticides, specifically limonene and methyl salicylate in contact/fumigation bioassays toward T. granarium adults. The results showed that methyl salicylate caused a lethal time of 50% (LT50) at the dose of 1 mg after 7.40 hours of exposure. The LT50 calculated for limonene was 86.83 hours while positive control using deltamethrin, used at the recommended dose of the manufacturer, was 5.20 hours after exposure. These data suggest that methyl salicylate can be exploited as a candidate for further tests in field conditions toward T. granarium also in consideration of its relative low toxicity for humans.