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The parasitoids of European gypsy moth Lymantria d. dispar (L.) and Lackey moth Malacosoma n. neustria (L.) in Greece were investigated. In total, twelve parasitoid species emerged from different larval instars of both species. Eight primary parasitoid species were recorded: three from the family Braconidae (Hymenoptera) and five from the family Tachinidae (Diptera). Four hyperparasitoid species of Cotesia neustriae (Tobias) and Glyptapanteles porthetriae (Muesebeck) (Braconidae) were reared belonging to the families Eurytomidae, Ichneumonidae and Pteromalidae (Hymenoptera). For the first time, Lysibia nana (Gravenhorst) (Hymenoptera: Ichneumonidae) is reported as a hyperparasitoid of C. neustriae and P. porthetriae. Our results are compared with the results of an exhausting and critical review of the literature on parasitoids of L. dispar and M. neustria in Europe. The parasitoid spectrums of L. dispar and M. neustria are compared and the parasitoid species in common are listed. According to literature 169 parasitoid species were associated with the investigated moths; 76 with L. dispar and 52 with M. neustria species belong only to their spectrums, respectively and only 41 parasitoid species are shared by both species.

The lackey moth, Malacosoma neustria (Linnaeus, 1758), a worldwide pest, causes extensive economic losses particularly on hazelnut, plum, oak, poplar, and willow trees. A baculovirus, Malacosoma neustria nucleopolyhedrovirus (ManeNPV-T2), has been isolated from the larvae collected in Turkey and appears to have a potential as a microbial control agent. In this study, we describe the complete genome sequence of ManeNPV-T2 and compare it to other sequenced baculovirus genomes. The ManeNPV-T2 genome is a circular double-stranded DNA molecule of 130,202 bp, has 38.2% G + C, and is predicted to contain 131 putative open reading frames (ORFs) each with a coding capacity of more then 50 amino acids. There are 27 ORFs with unknown function of which 6 are unique to ManeNPV-T2. Eleven homologous regions (hrs) and two bro genes (bro-a and bro-b) were identified in the genome. There are two homologues of chaB and nicotinamide riboside kinase-1 genes, separated from themselves with a few nucleotides. Additionally, ac145, thought to be per os infectivity factor (pif) gene, is also found as two homologues. All 38 core genes are found in the ManeNPV-T2 genome. The phylogenetic tree of ManeNPV-T2 in relation to 50 other baculoviruses whose genomes have been completely sequenced showed ManeNPV-T2 to be closely related to the group II NPVs. This study expands our knowledge on baculoviruses, describes the characterization ManeNPV, and ultimately contributes to the registration of this virus as a microbial pesticide.

Zusammenfassung und Diskussion Auf Grund der beschriebenen Beobachtung in den Vorratszuchten des Ringelspinners (Malacosoma neustria L.) wurde angenommen, das fur die kleinen, kunstlich verspateten Raupchen, das gewohnliche, im Mai erschienene Blatt bereits zu hart war. Durch Storung des sychronen Entwicklungsverlaufs von Blattern und Raupen wurde das Uberleben der letzteren ernstlich gefahrdet. Die beiden ersten Versuche, in denen die Raupen gefuttert wurden mit Blattern von normal und zufallig spater ausgeschlagenen Eichen sowie mit normalen Blattern und Johannislaub, bestatigten bereits diese Annahme. Leider musten die Versuche, lange bevor die Raupen ausgewachsen waren, beendet werden. Im dritten und letzten Versuch gelang es, die Raupen sowohl mit Mai- als mit Johannislaub am Leben zu halten. Genau wie bei den beiden ersten Versuchen war die Mortalitat der mit dem frischen Laub gefutterten Raupen bedeutend kleiner und das Wachstum schneller als bei den mit alten Blattern ernahrten. Spater ergab sich, das auch Puppengewicht und Eiproduktion bedeutend hoher lagen sowie die Verpuppung eher begann. Bezuglich der Zuchten mit Maiblattern des letzten Versuches mas darauf hingewiesen werden, das von 60 Raupen (♂ und ♀) nur 1(!) Weibchen ubrigblieb, in dessen Ovarium 83 Eier gezahlt wurden. Wenn diese Eier alle befruchtet und tatsachlich abgelegt waren, wurde sich aus dieser Gruppe von 60 Stuck eine Gruppe von 83 Stuck im Ei-Stadium entwickelt haben. Hiervon durfte zweifellos noch eine Anzahl eingegangen sein, bevor sie das Stadium des ursprunglichen Versuchsmaterials erreicht hatte. Zudem wurden Predatoren und Parasiten durch den Maschendraht von den anfanglich 60 Tieren ferngehalten. Im Freien ware eine derartige Population also sicher eingegangen, auch weil das im Vergleich mit dem anderen verlangerte Larvenstadium (um ca. 21 Tage) die Gefahr von Predation und Parasitierung bedeutend vergrosert haben wurde. Jedoch mus bemerkt werden, das im Freien wahrscheinlich niemals eine derartig grose Storung in der synchronen Entwicklung auftreten durfte. Die Tatsache, das alte Blatter nur skelettiert wurden und junge ganzlich gefressen, zeigt uns, das Strukturunterschiede des Blattes eine der Ursachen, wahrscheinlich der Hauptgrund, sind fur die unterschiedlichen Zuchtergebnisse. Moglicherweise hat auch der hohere Wassergehalt des jungen Blattes gunstig gewirkt. Dieses ist um so wahrscheinlicher, weil die Versuchstiere aus dem Blatt ihr Wasser beziehen musten. Der gunstige Einflus des verspateten Maiblattes und des Johannislaubes konnte auftreten trotz dem im Vergleich mit dem Maiblatt geringeren Zukker- und Roheiweisgehalt. Naturlich ist es auch moglich, das noch andere Stoffe mitgewirkt haben, z. B. ein Ubermas von wachstumsfordernden Stoffen im jungen Blatt oder giftig wirkenden im alten Blatt. Wir haben jedoch diesbezuglich keine Beobachtungen gemacht. Im Zusammenhang mit dem geringeren Zuckergehalt sei darauf hingewiesen, das nach Schwenke (1962, 1963 und 1966) das Erscheinen phythophager Insekten gefordert wird durch hohen Zuckergehalt, u. a. bei Diprion pini L. Weil aber die Konditionen, mit denen Schwenke seine Resultate erhielt, grundverschieden waren von den meinigen, will ich den Einflus des Zuckers hier nicht weiter diskutieren. Aus allen Resultaten durfen wir den Schlus ziehen, das unsere ursprungliche Auffassung richtig war, das also eine Storung in der synchronen Entwicklung des Eichenlaubs und der Ringelspinnerpopulation eine geringere Populationsdichte des letzteren verursachen kann. Es ist jedoch nicht wahrscheinlich, das im Freien eine derartig grose Storung, die wir ungewollt erzielten, auftreten wird. Es ist Vorsicht geboten beim Verzogern der Entwicklung der Ringelspinnereier, wenn das Material dazu dienen soll, den Einflus der Nahrungspflanze auf die allgemeine Entwicklung des Insektes zu prufen. Summary The investigations described in this paper are the result of a coincidence occurring in rearing cages containing the stock of lackey moths (Malacosoma neustria L.), which was intended for other experiments. In these cages some of the caterpillars were observed to skeletonize the leaves while the others ate the entire leaves. The skeletonizing caterpillars grew little or not at all. As the eggs had been kept at 5° C for some three weeks in spring we suspected that the synchronization between the development of the caterpillars and of the food plant, viz. the pedunculate oak (Quercus robur L. = Q. pedunculata L.) had been disturbed, so that a proportion of the caterpillars starved. Three experiments were made in order to investigate the question. In the first experiment a group of caterpillars was fed with the soft leaves of some oaks which had budded late for some reason. These caterpillars grew much faster than the controls on May-leaves. This result confirmed the hypothesis stated above. It also led to the conclusion that in the field a population of the lackey moth will thrive better the more closely the development of the caterpillars is synchronized with that of the leaves. The experiment had to be discontinued because the caterpillars weakened too much and because soft leaves were no longer available in the vicinity of the laboratory. In the second experiment the midsummer growth, of oak, i. e. the shoots formed about the end of June, was used as food for the caterpillars. On this food the caterpillars also developed better than on the May-leaves. The experiment had to be discontinued because the controls (the caterpillars on May-leaves) died. In the last experiment we succeeded in keeping the caterpillars alive on the May-leaves as well as on the leaves of the midsummer growth. In this experiment the mortality of the caterpillars was also lower and the growth faster on the midsummer leaves than on the May-leaves. In addition it appeared that pupal weight and egg-production were greater and that pupation took place earlier on midsummer-leaves than on May-leaves. It has thus become likely that the differences in growth, mortality etc. are largely the result of differences in the structure of the leaves. Chemical analysis showed, that the midsummer-leaves contained more water and less sugar and protein than the May-leaves. Possibly also the high water content of the soft leaves was of advantage to the caterpillars. It is remarkable that the caterpillars thrived better on the young leaves and the midsummer-leaves, in spite of the low sugar and protein content. It is concluded that the hypothesis stated above is correct, and that a disturbance of the synchronization between the development of the leaves of the oak in spring and the development of the caterpillars of the lackey moth may cause a decrease of the population density of the insect. It is not to be expected, however, that in the field the disturbance will be as great as the one in the rearing cages. Care should be exercised when it seems necessary to slow down the development of the eggs of the lackey moth, when the caterpillars are to be used for investigations on the influence of the food on the development.

The lackey moth, Malacosoma neustria (Linnaeus, 1758), a worldwide pest, causes extensive economic losses on particularly hazelnut, Prunus, Quercus, Populus, and Salix trees. In this study, a local nucleopolyhedrovirus (NPV) was isolated from the larvae of M. neustria in the northeast of Turkey. It was named ManeNPV-T2. Electron microscopic observations showed that the polyhedra of the new isolate contain several virions with multiple nucleocapsids packaged within a single viral envelope. Restriction endonuclease analysis of ManeNPV-T2 DNA indicated that it has a different restriction profile compared to the previous Turkish and Latvian isolates. The phylogenetic analysis of the amplified polh sequence of ManeNPV-T2 showed its relation to the other NPVs from Malacosoma species. Mortality values for third instar M. neustria larvae ranged from 48% to 100% according to the concentration of polyhedral occlusion bodies. Based on screening tests, the LD50 value of the new isolate was calculated as 1.34 × 104 occlusion bodies per larvae. Consequently, ManeNPV appears to be a promising microbial control agent for biocontrol of M. neustria.

Summary The woody vegetation adjacent to the Pembrokeshire Coast Path was recorded along nine sections of the pathway in particularly exposed locations, together totalling 23.7km. The presence of larvae of the eggar moth and the lackey moth was also noted. Records were made every hundred metres. The majority of the sampling stations contained no shrubs. Blackthorn occurred at 17.3 per cent of stations; hawthorn at 6.8 per cent; elder at 3.0 per cent. All other species occurred at 1 or 2 stations (0.4 and 0.8 per cent respectively). These findings contrasted with the shrub flora of a sheltered inlet; and with the picture for Wales as a whole. The coastal situation in Pembrokeshire is compared with the Cornish coast and with the altitudinal limits of shrubs in Wales and England. The inter-relationships in the moth larvae data are also discussed.

The lackey moth Malacosoma neustrium (L.) (Lepidoptera Lasiocampidae) is a common pest of many forest and cultivated broadleaf trees. Analysis by GC-EAD of gland extracts and female effluvia showed the presence of two active peaks that were characterized as (E,Z)-5,7-dodecadienal (E5,Z7-12:Ald) and (E,Z)-5,7-dodecadienol (E5,Z7-12:OH) according to their GC retention times, mass spectra, and electroantennographic activity. (E,Z)-5,7-dodecadienyl acetate (E5,Z7-12:Ac) was also detected in the gland extracts. The average amounts of E5,Z7-12:Ald, E5,Z7-12:OH, and E5,Z7-12:Ac extracted from an abdominal tip were 113.2 +/- 22.0 ng, 29.9 +/- 6.2 ng, and 11.6 +/- 2.0 ng, respectively. In the effluvia from single females, on the average, 1.9 +/- 0.7 ng/min of aldehyde and 0.3 +/- 0.1 ng/min of alcohol were collected. In wind tunnel tests, male behavioral sequences elicited by E5,Z7-12:Ald alone or in 3:1 and 9:1 blends with the corresponding alcohol were similar to those evoked by one female equivalent of sex pheromone gland extract. Field trapping experiments showed that E5,Z7-12:Ald is essential to attract male moths. On adding E5,Z7-12:OH to E5,Z7-12:Ald in 1:3 and 1:9 ratios, male attraction slightly increased whereas in a 1:1 ratio, the attractiveness of E5,Z7-12:Ald was reduced.

Caterpillars of some moths feed gregariously, for at least part of their lives, in communal silken webs or ‘tents’ which they spin on their food plants. Some species which have this habit and are economically important in Britain are described here. These species are the small ermine moths (Yponomeutaspp.), the lackey moth (Malacosoma neustria (L.)) and the brown-tail moth (Euproctis chrysorrhoea (L.)). The vapourer moth (Orgyia antiqua (L.)), whose caterpillars occur together in large numbers though not feeding within webs, is also included.

There are two kinds of caterpillars which every year commit serious depredations in our Canadian apple orchards, although they by no means confine their attentions to that tree. These are the larvæ of the American and Forest Lackey Moths, two species of brown moths which frequently fly into houses at night during July, and draw attention by their headlong, reckless flight, dashing themselves against the ceiling and the walls, and very often finishing up by getting into the lamp chimney.