Astronomical orientation and learning in the earwig Labidura riparia

Astronomical orientation experiments have been carried out on adults and young of the earwig Labidura riparia. In the water, the earwigs

1.

(1) assumed a correct landward orientation, concordant with their home shore;     

Presence of an adipokinetic peptide in the corpus cardiacum of Dermaptera but not in the neurohaemal aorta, and chemical and functional identification of the peptide

Corpora cardiaca of the earwigs Labidura riparia and Forficula auricularia contain a substance that causes hyperlipaemia in migratory locusts and hypertrehalosaemia in the American cockroaches. A conspecific bioassay in L. riparia revealed that this factor is lipid-mobilizing. Isolation of the neuropeptide was achieved by single-step RP-HPLC. The primary structure of the earwig adipokinetic peptide was elucidated by automated Edman degradation in combination with matrix-assisted laser desorption/ionization mass spectrometry. It is a blocked octapeptide, pGlu-Val-Asn-Phe-Ser-Thr-Gly-Trp-NH₂, previously denoted as Grb-AKH and first identified in Gryllus bimaculatus ( Gäde & Rinehart 1987 ). The synthetic peptide co-chromatographed under various conditions with the native peptide and, in biological assays, resulted in lipid-mobilization in L. riparia when injected in low concentration.     

Right-handed penises of the earwig Labidura riparia (Insecta, Dermaptera, Labiduridae): evolutionary relationships between structural and behavioral asymmetries

The number of penises vary in the insect suborder Forficulina (order Dermaptera; earwigs). Males of the families Diplatyidae, Pigidicranidae, Anisolabididae, Apachyidae, and Labiduridae have two penises (right and left), while those of the Spongipohridae, Chelisochidae, and Forficulidae have a single penis. The proposed phylogenetic relationships among these families suggest that the single‐penis families evolved from an ancestor possessing two penises. To date, examinations of double‐penis earwig species have found that only a single penis is used per single copulation. These diversities in structural and behavioral aspects of genitalia raises the following intriguing questions: How are the two penises used? Why did a penis degenerate in several earwig families, and which one was lost? To address these questions, structural and behavioral asymmetries were examined in detail for a representative species Labidura riparia (Labiduridae). Although there was no detectable morphological differentiation between the right and left penises, male L. riparia predominantly used the right one for insemination. This significant “right‐handedness” developed without any experience of mating and was also manifested in the resting postures of the two penises when not engaged in copulation. However, surgical ablation of the right penis did not influence the insemination capacity of males. In wild‐caught males, only about 10% were left‐handed; within this group, abnormalities were frequently observed in the right penis. These lines of evidence indicate that the left penis is merely a spare intromittent organ, which most L. riparia males are likely never to use. Additional observations of five species of single‐penis families revealed that the left penis degenerated in the common ancestor of this group. Considering the proposed sister relationship between the Labiduridae and the single‐penis families, it is possible that such behavioral asymmetries in penis' use, as observed in L. riparia, are parental to the evolutionary degeneration of the infrequently used left penis. J. Morphol., 2006. © 2006 Wiley‐Liss, Inc.     

Partial characterization and isolation of earwig `allatostatins'': biological activities in earwigs and cockroaches

Allatostatins are a family of neuropeptides first isolated from the cockroach, Diploptera punctata, that inhibit juvenile hormone production in that species (but do not do so in earwigs), and inhibit hindgut muscle contractions in some insects, including the earwig, Euborellia annulipes. We examined whether material from earwig brains is similar to cockroach allatostatins biochemically, immunologically and physiologically. Brain extracts from adult female earwigs were separated by high performance liquid chromatography (HPLC), followed by radioimmunoassay using antibodies to cockroach allatostatin (Dip-AST). Fractions that co-eluted with cockroach allatostatins were immunoreactive, and at least two peaks of immunoreactivity were detected. Material from each peak at 10 nM Dip-AST equivalents inhibited juvenile hormone biosynthesis in vitro by corpora allata of 2-day virgin D. punctata cockroaches; 1 nM was less effective, and non-immunoreactive fractions failed to inhibit juvenile hormone biosynthesis. Both crude and Sep-Pak (Waters) purified extracts of brains of earwigs containing 1 nM Dip-AST equivalents failed to suppress hindgut contractions in vitro of 2-day earwigs and of brooding female earwigs. In contrast, 1 nM cockroach allostatin 1 (Dip-AST 7) reversibly inhibited hindgut contractions in vitro. These results suggested the presence of another brain factor, such as proctolin, that counteracts the inhibitory effects of Dip-AST. In support of this hypothesis, proctolin stimulated hindgut contractions in vitro at 1 nM; the effects of equal concentrations of allatostatin and proctolin varied with the stage of the female. Furthermore, HPLC-separated fractions that co-eluted with cockroach allatostatin and were immunoreactive with antibodies to Dip-AST suppressed hindgut contractions in vitro of 2-day female earwigs. Finally, crude brain extracts of earwigs suppressed earwig juvenile hormone biosynthesis in vitro in glands of low, but not in glands of high, activity. Thus, earwig brain extract after HPLC separation has Dip-AST-like material that inhibits cockroach corpora allata and suppresses earwig hindgut contractions. Sep-Pak-extracted earwig brain material, however, does not inhibit earwig gut contraction. Although synthetic Dip-AST 7 does not inhibit juvenile hormone synthesis by earwig corpora allata, there is heat-stable material in earwig brain extract that does have this action.     

European earwig (Forficula auricularia) as a novel host for the entomopathogenic nematode Steinernema carpocapsae

The natural history of many entomopathogenic nematode species remains unknown, despite their wide commercial availability as biological control agents. The ambushing entomopathogenic nematode, Steinernema carpocapsae, and the introduced European earwig, Forficula auricularia, forage on the soil surface. Since they likely encounter one another in nature, we hypothesized that earwigs are susceptible to nematode infection. In the laboratory, the LC₅₀ for F. auricularia was 226 S. carpocapsae/earwig and the reproductive potential was 123.5 infective juvenile nematodes/mg tissue. This susceptibility depended on host body size with significantly higher mortality rates seen in larger earwigs. In a study of host recognition behavior, S. carpocapsae infective juveniles responded to earwig cuticle as strongly as they did to Galleria mellonella cuticle. We also found that earwigs exposed to S. carpocapsae cleaned and scratched their front, middle and back legs significantly more than controls. Coupled with previous field data, these findings lead us to suggest that F. auricularia may be a potential host for S. carpocapsae.     

Sexual differences in foraging on corn of adultLabidura riparia [Derm.: Labiduridae]

A significantly greater number of adult femaleLabidura riparia (Pallas) was found foraging on corn (male: female, 1:4.16) than were expected from the male: female ratio (1:1.63) caught in pitfall traps. Nymphs reared to adulthood from both corn plants and pitfall traps indicated nymphs forage without respect to sex. Adult female earwigs killed significantly moreDiabrotica balteata Le Conte adults than did male earwigs at 2 higher diet levels of a functional response experiment. This apparent requirement of the female for more food than the male is offered as an explanation of the differences in their foraging activity.     

Natural and human causes of earwig mortality during winter: temperature,parasitoids and soil tillage

Beneficial arthropods are often used for suppressing specific pest outbreaks in agricultural crop systems. The European earwig, Forficula auricularia L., (Dermaptera: Forficulidae), is an important natural enemy in fruit orchards. Recently, ecological studies were published describing earwig dispersal and survival during summer, hereby revealing clear differences between populations with a single brood (SBP) and two broods a year (DBP). In this article, we will describe three potential mortality factors of earwigs during the underground winter period, namely cold temperatures, parasitoids and soil tillage. This knowledge is essential for making efficient management strategies for increasing earwig abundance in fruit orchards. The effect of cold temperatures was checked during a 3‐year semi‐field experiment. Parasitism rates of Triarthria spp. (Fallén) and Ocytata pallipes (Fallén) (Diptera: Tachinidae) were obtained in a rearing experiment. The negative effect of soil tillage on the survival of earwigs nests was checked in a field experiment covering a 4‐year time period. A strong, negative relation between temperature [cooling day degrees (CDD)] and survival of female and male earwigs during winter was found. Male earwigs of SBP died very quickly, mimicking natural conditions. Between 60% and 90% of females do not survive winter. Survival of females in DBP was higher than in SBP. Parasitism rates vary a lot between species, generation, year and location (0–20%). During winter, we found a maximum mortality of 13%. There is a clear trend that soil tillage can reduce the number of nymphs in spring and summer by 50%. Implications for biocontrol are the following: (i) mortality owing to temperature can be predicted using CDD and if necessary preventive management actions can be undertaken to control pests; (ii) parasitism rates are negligible compared to high impact of temperature; and (iii) soil tillage can be timed more accurately using a recently developed day degree model.     

Host-parasite relationship of Angiostrongylus cantonensis in Lymnaea palustris. III. Oxygen uptake of Lymnaea palustris.

Oxygen uptake rates by Lymnaea palustris infected with Angiostrongylus cantonensis and by noninfected controls were determined at 25, 30, and 35 C over 34-day periods. Significant decreases in oxygen uptake were noted from one day to the next for both infected and noninfected groups of snails. At 25 and 30 C groups of infected snails found to have high average larval recoveries frequently had significantly higher oxygen uptake rates than for corresponding groups of noninfected snails. At 35 C readings were less reliable due to an increase in mortality for both infected and noninfected snails. Respiratory rates were not significantly altered by increasing the temperature from 25 to 30 and 35 C.     

Dispersal of single‐ and double‐brood populations of the European earwig,Forficula auricularia: a mark‐recapture experiment

Quantitative information on dispersal of insects should be taken into consideration for making efficient pest management decisions. Such information was not available for the European earwig, Forficula auricularia L. (Dermaptera: Forficulidae), an important biocontrol agent in fruit orchards. A mark‐recapture experiment was carried out in Belgian orchards, where marked earwigs were released at a single point and recaptured after 1 month. Dispersal from this release point was analysed using an analytical formula of a simple diffusion model with disappearance (e.g., as a result of death) derived by Turchin & Thoeny (1993; Quantifying dispersal of southern pine beetles with mark‐recapture experiments and a diffusion model. Ecological Applications 3: 187) . The cumulative number of recaptured earwigs as a function of the distance of release was used to fit the model and estimate parameters. A derived expression, in terms of these parameters, was used to estimate the frequency distribution of the population, as the radius of a circle enclosing various proportions of the earwigs’ dispersal distances. In Belgium, populations of the European earwig can have two life‐history strategies, single‐ (SBP) and double‐brood populations (DBP). Therefore, mark‐recapture experiments were carried out on both population types. We fitted data from SBP (n = 10) and DBP (n = 16) successfully in both the diffusion model and in an exponential curve. Because of the biological relevance, estimates of the diffusion model were used for calculating the frequency distributions. Males and females dispersed the same distances. No differences were found between orchards with different spatial structures (apple and pear). According to literature data, mobility of earwigs is very low compared with other arthropods, which has consequences for the efficiency of biocontrol interventions, like mass releases of earwigs or the use of hedgerows for the establishment of healthy (source) populations. Quantitative results revealed that earwigs of SBP dispersed four times further than earwigs of double‐brood populations. For instance, 95% of the population remained within a radius of 28.6 m in SBP and 7.54 m in DBP.     

Predation potential of the earwig Euborellia annulipes on fruit fly larvae and trophic interactions with the parasitoid Diachasmimorpha longicaudata

The earwig Euborellia annulipes (Lucas) (Dermaptera: Anisolabididae), a generalist predator, has been observed in fruits infested with fruit fly larvae, which are frequently parasitized by parasitoid wasps. Neither the capacity of earwigs to predate on fruit flies nor intraguild interactions between earwigs and fruit fly parasitoids have been investigated. Here, we studied in laboratory conditions the predation on the fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) by the earwig E. annulipes, and whether parasitism of fruit fly larvae by the parasitoid wasp Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) influences predation by the earwig. We evaluated the predation capacity, functional response and prey preference of E. annulipes for parasitized and non-parasitized fruit fly larvae in choice and no-choice tests. We found that earwigs prey on second- and third-instar larvae and pupae of C. capitata and consumed larger numbers of second-instar larvae, followed by third-instar larvae and pupae. Females prey on larger numbers of fruit flies than did males, regardless of the prey developmental stage, but both sexes exhibited a type II functional response. Interestingly, males killed but did not consume fruit fly larvae more than did females. In no-choice tests, earwig females consumed equal numbers of parasitized and non-parasitized fruit fly larvae. However, in choice tests, the females avoided feeding on parasitized larvae. Subsequent tests with hexane-washed parasitized and non-parasitized larvae showed that putative chemical markings left on fruit flies by parasitoids did not drive the earwig preference towards non-parasitized larvae. These findings suggest that E. annulipes is a potential biological control agent for C. capitata, and that, because the earwig avoids consuming larvae parasitized by D. longicaudata, a combination of the two natural enemies could have an additive effect on pest mortality.     

Effects of the concurrent exclusion of ants and earwigs on aphid abundance in an organic citrus grove

Based on the well-known mutualism between ants (Hymenoptera: Formicidae) and aphids (Homoptera: Aphididae), we conducted a five-year experiment of ant-exclusion from the canopies of citrus trees as a possible method of biological control of aphids. However, our results showed that the exclusion of ants from the canopies increased, instead of reducing, aphid abundance. To explain this unexpected result, we reasoned that the exclusion of ants from the canopies might also have excluded crawling insects that prey on aphids, such as the European earwig (Forficula auricularia L., Dermaptera: Forficulidae). Such a possibility is supported by the negative relationship between aphid density and the abundance of earwigs, consistent with a top-down control of aphids by earwigs. In contrast, the abundance of other aphid predators (Coleoptera: Coccinellidae, and Heteroptera) had no such negative effect on aphid density but a positive one, suggesting a bottom-up control, and showed no differences between control and ant-excluded trees. Thus, the most likely explanation for the increase in aphid abundance in the ant-excluded trees is the absence of earwigs from the canopies of the experimental trees, providing further evidence of the major role that earwigs play as control agents of aphids in cultivated trees.     

Parasitism of the common earwigForficula auricularia [Dermaptera: Forficulidae] by tachinid flies in an apple orchard

Earwigs (Forficula auricularia L.) were collected from an untreated apple orchard every 2 weeks from June to October 1979. Percentage parasitism at the times of collection was calculated from the numbers of parasitoids that emerged. Two tachinidsRhacodineura pallipes Fallen andDigonochaeta spinipennis Meigen parasitised earwigs, starting between 21 June and 5 July and continuing through July. Parasitism byR. pallipes reached a peak of 16 % in late July; fewer earwigs were parasitised byD. spinipennis. Both tachinids had one generation per year;D. spinipennis overwintered as puparia, andR. pallipes as larvae in earwig hosts or as adults. In the orchard, puparia of both tachinid species were hyperparasitised byDibrachys cavus (Walker) (Pteromalidae) andPhygadeuon vexator (Thunberg) (Ichneumonidae).     

Multifunctional weaponry: The chemical defenses of earwigs

Earwigs protect themselves against predators using pincer-like cerci and/or malodorous exudates secreted from abdominal glands. Little is known about the chemistry of these secretions and their potential functions. However, because earwigs live in aggregations and overwinter in soil, they are exposed to high microbial loads throughout their lifecycle, and we therefore hypothesized that the secretions are used not only to deter predators but also to combat pathogens and parasites in their environment. We analyzed the defensive secretions of the European earwig Forficula auricularia, the short-winged earwig Apterygida media and the woodland earwig Chelidurella guentheri by gas chromatography–mass spectrometry. The secretions of all three species contained 2-methyl-1,4-benzoquinone and 2-ethyl-1,4-benzoquinone, whereas A. media also produced 2,3-dimethyl-1,4-benzoquinone and 2-ethyl-3-methyl-1,4-benzoquinone. The latter has not been identified in the exudates of insects before. The composition and/or quantity of these components were species-specific and partially sex-specific. All secretions showed antimicrobial activity against Gram-positive and Gram-negative bacteria as well as two entomopathogenic fungi. Furthermore, the secretion of F. auricularia displayed nematicidal activity against Caenorhabditis elegans. Our data support the hypothesis that earwig secretions are multifunctional, serving both to deter predators and sanitize the microenvironment.     

Compatibility between Forficula auricularia and entomopathogenic nematodes to be used in pome fruit pest management

Use of predators, parasitoids and entomopathogens as biocontrol agents in pome fruit production can lead to more efficient and sustainable pest management programmes. The European earwig (Forficula auricularia Linnaeus [Dermaptera: Forficulidae]) is a major predator of key pests in pome fruit orchards, and entomopathogenic nematodes (EPNs) of the families Steinernematidae and Heterorhabditidae are obligate parasites of a large number of insect species. Therefore, the interaction between earwigs and EPNs can play an important role in pest management programmes. Susceptibility of the European earwig to Steinernema carpocapsae, Steinernema feltiae (Steinernematidae) and Heterorhabditis bacteriophora (Heterorhabditidae) was evaluated. S. carpocapsae was the only tested EPN capable of killing the European earwig. However, the European earwig can detect the presence of S. carpocapsae and therefore avoid nematode‐treated shelters. An earwig deterrent activity in EPN‐killed codling moth larvae that reduces the foraging of European earwig on insect cadavers containing nematodes and allows nematodes to complete their life cycle was also assessed with the three species of nematodes. These findings suggest a positive compatibility between the European earwig and EPNs.     

Biology and host range testing of Triarthria setipennis and Ocytata pallipes (Diptera: Tachinidae) for the control of the European earwig (Forficula auricularia)

The European earwig (Forficula auricularia) is an invasive species in the Falkland Islands, causing considerable problems for local horticulture, as well threatening indigenous ecosystems. To assess the potential of a classical biological control introduction two parasitoid fly species, Triarthria setipennis and Ocytata pallipes (Diptera: Tachinidae), were collected from sites in southern and northern England and then tested for their suitability as earwig biological controls at Egham, UK. Both species had previously been introduced into North America for earwig control however little is known of their long-term efficacy and host specificity. Host range tests including both target and non-target species were done. As there are no native Dermaptera on the Falkland Islands, tests were restricted to the field cricket Gryllus assimilis and the Dubia cockroach Blaptica dubia, as representatives of insect orders phylogenetically closely related to earwigs. A second cricket species (Gryllus bimaculatus) was included in an egg-depositing experiment for O. pallipes. Both tachinid species successfully parasitised and emerged from earwigs under laboratory conditions but no signs of parasitisation and development were observed in either the cricket or cockroach.     

Effect of Phytotoxin from Nematode-induced Pinewilt on Bursaphelenchus xylophilus and Ceratocystis ips

A phytotoxic extract from Pinus sylvestris infected with Bursaphelenchus xylophilus inhibited growth of the blue-strain fungus Ceratocystis ips and caused temporary paralysis in vitro of B. xylophilus. Although the nematodes recovered from paralysis, final population size of B. xylophilus was suppressed by the toxin. Extracts from noninfected P. sylvestris affected neither the fungus nor the nematode.     

Earwig preying on ambrosia beetle: Evaluating predatory process and prey preference

Earwigs (Dermaptera), such as Forficula auricularia L., are important euryphagous predators for a wide variety of prey and can markedly influence the populations of orchard pests. Most previous studies on earwig feeding behaviour have not used adult beetles of the prey species; few researchers have focused on prey preference in earwigs. Some fragments of beetle exoskeleton and an earwig adult, Anisolabella marginalis (Dohrn), were found in the same cage, where adults of ambrosia beetle, Euwallacea interjectus (Blandford), were emerging from the logs of a fig tree infected with Ceratocystis canker (fig wilt disease). Thus, A. marginalis was suspected of being a predator of E. interjectus. To shed light on this issue, in the laboratory, we set up a test arena and observed and recorded behavioural interactions between A. marginalis and E. interjectus. E. interjectus was collected from the logs of fig trees and reared on an artificial diet, along with six different ambrosia beetle species, which were collected from a trap (baited with ethanol) and a fallen maple tree. A series of laboratory experiments demonstrated that A. marginalis is actually a predator of E. interjectus and other species of ambrosia beetle, indicating its a potential for use in effective pest control in the field. The predators frequently consume and tend to select their prey depending on prey size, rather than sex and beetle species. Furthermore, earwigs have alternative predatory strategies for dealing with seven different species, although they use their forceps to cut the body of most tested beetles.     

Predictive thresholds for forecasting the compatibility of <Emphasis Type="Italic">Forficula auricularia</Emphasis> and <Emphasis Type="Italic">Aphelinus mali</Emphasis> as biological control agents against woolly apple aphid in apple orchards

The woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann) (Hemiptera: Aphididae) is a well-known pest of apple orchards world-wide. Several studies have demonstrated variable control of WAA populations by the European earwig, Forficula auricularia (L.) (Dermaptera: Forficulidae) and the WAA parasitoid Aphelinus mali (Halderman) (Hymenoptera: Aphelinidae). We examine whether a beneficial interaction between F. auricularia and A. mali exists and calculate optimal numbers for each species to maintain WAA infestations below acceptable levels. We demonstrate that trees possessing >14 earwigs per trunk trap per week within the first seven weeks post-blossom contained WAA infestations well below acceptable levels. Where these earwig thresholds were not met, a first generation of A.mali greater than 0.5 wasps per tree was required. If these beneficial insect targets were not met, severe WAA infestations occurred. Our findings suggest that if F. auricularia and A. mali numbers exceed these thresholds chemical intervention may not be required.     

Earwig (Forficula auricularia) predation on the woolly apple aphid, Eriosoma lanigerum

Woolly apply aphid predation by the common earwig, Forficula auricularia L., and other predators was compared in high, intermediate and low earwig density plots of mature apple trees at an experimental orchard in the Netherlands. Aphid colonies were discovered and exterminated primarily by earwigs much more rapidly in the high and intermediate earwig density plots than in the low density plots. Where earwigs were excluded from trees by Tanglefoot bands around the trunks, woolly apple aphids infested 30–35% of new growth shoots whereas less than 10% of the shoots were infested where earwigs were relatively abundant.Several factors including the availability of alternate prey (e.g. Aphis pomi De Geer), earwig developmental phenology and weather probably influenced the outcome of the predation experiments. Nevertheless earwigs play an important role in suppressing woolly apple aphid populations and are potentially important, naturally occurring biological control agents for this pest.

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Résumé L'action prédatrice exercée sur le puceron lanigère par le perceoreille commun, Forficula auricularia, et par d'autres prédateurs, a été comparée dans des parcelles d'un verger expérimental de pommiers adultes aux Pays-Bas. Ces parcelles étaient caractérisées par des densités fortes, intermédiaires, et basses en perce-oreilles. Les colonies de pucerons ont été découvertes et exterminées principalement par les perce-oreilles beaucoup plus rapidement dans les parcelles à forte et moyenne densité de perce-oreilles que dans celles à faible densité. Les pucerons lanigères ont colonisé 30 à 35% des nouvelles pousses lorsque les perce-oreilles étaient exclus par une barrière mécanique (Tanglefoot), alors que moins de 10% des pousses ont été infestées lorsque les perce-oreilles étaient relativement abondants.Plusieurs facterus ont probablement influencé le résultat des expériences de prédation, notamment la présence de proies alternatives (par exemple Aphis pomi), la phénologie du développement des perce-oreilles et le climat. Néanmoins, les perce-oreilles ont joué un rôle important en limitant les populations du puceron lanigère, et constituent potentiellement d'importants agents de contrôle naturel de ce ravageur.

     

Abundance,interannual variation and potential pest predator role of two co‐occurring earwig species in citrus canopies

Earwigs are usually considered pest predators in orchards. Because of its worldwide distribution, most research on earwigs focuses on the European earwig Forficula auricularia Linnaeus (Insecta: Dermaptera: Forficulidae). However, very little is known of this species in Mediterranean citrus orchards. Earwigs and aphids were collected monthly during 5 years (2006–2010) from citrus canopies. Two species of earwigs were found: F. auricularia and Forficula pubescens Gené (=Guanchia pubescens), with the latter seldom cited in the literature. The goals of this study were (i) to document the abundance of these two earwig species in Mediterranean citrus canopies; (ii) to determine whether they are positively or negatively associated with each other, or randomly distributed; (iii) to measure the interannual variation of the abundance of both species during a 5‐year period and (iv) to evaluate the potential role of earwigs as pest predators in citrus canopies. As compared to colder regions, F. auricularia active period in citrus canopies in our study site lasted longer. Both species co‐occurred randomly in canopies. In 2006, both species showed approximately the same abundance, but in 2010, F. pubescens abundance in canopies was 28 times greater than that of F. auricularia. The potential role of earwigs as pest predators is higher in the Mediterranean than in other colder regions, because of the longer active period. F. auricularia is a sedentary generalist predator, already present in citrus canopies at the onset of most pest outbreaks, while F. pubescens arrived later to the canopies, but most likely was abundant enough to contribute in the control of citrus pests.