Maria Concetta Rizzo

ON TWO ITALIAN GALL MIDGES (DIPTERA CECIDOMYIIDAE) AND THEIR PARASITOIDS.

Some biological data on Cystiphora sonchi (Bremi) and Asphondylia trabuti Marchal in Italy are reported. C. sonchi, previously known only for N Italy, is also recorded for S Italy, Sardinia and Sicily. It induces galls on the leaves of Sonchus spp. (Compositae) all the year around, except for the second half of July and August. The number of galls per leaf was higher in summer (11.6) than in winter (7.4). Overall 5-6 generations per year were observed, with a maximum number of individuals in spring-summer. Larvae often merge in the same gall, pupating inside it and emerging from the lower leaf surface; in winter they can leave galls and pupate outside them. On the whole 426 C. sonchi and 381 parasitoids were reared; 359 were Aprostocetus microscopicus (Rondani) (Hymenoptera Eulophidae) and 22 Synopeas larides (Walker) (Hymenoptera Platygasteridae); the latter has not been previously quoted for Italy. A. trabuti, previously known as phytophagous on fruits of Solanum tuberosum L., is here recorded for the first time in Italy and as phytophagous of S. nigrum L. Larvae live gregariously, developing and pupating inside fruits between May and December. They emerge in about two weeks, their number peaking in spring; at least 5 generations per year were observed. On the whole 100 A. trabuti and 91 parasitoids were reared; 88 were Eurytoma dentata Mayr (Hymenoptera Eurytomidae), previously unrecorded as parasitoids of this gall midge, and 3 were unidentified Pteromalidae. Key words: Cystiphora sonchi, Asphondylia trabuti, Sonchus spp., Solanum nigrum. SU DUE SPECIE ITALIANE DI CECIDOMIDI GALLIGENI E SUI LORO PARASSITOIDI Si riportano alcuni dati biologici su Cystiphora sonchi (Bremi) ed Asphondylia trabuti Marchal (Diptera Cecidomyiidae) in Italia. C. sonchi era nota solo per le regioni settentrionali e viene riportata ora anche per l’Italia meridionale, la Sardegna e la Sicilia; essa induce galle sulle foglie delle specie del gen. Sonchus (Compositae) durante tutto l’anno divenendo rara nel periodo meta luglio-agosto. Il numero di galle estive per foglia (11,6) e risultato piu alto di quelle inver- nali (7,4). In totale sono state osservate 5-6 generazioni per anno con un picco numerico in pri- mavera-estate. Le larve spesso confluiscono nella stessa galla e vi si impupano, sfarfallando dalla pagina inferiore; in inverno alcune larve abbandonano le galle e si impupano aldifuori di esse. In totale sono stati allevati 426 C. sonchi e 381 parassitoidi, 359 dei quali sono risultati Aprostocetus microscopicus (Rondani) (Hymenoptera Eulophidae), 22 Synopeas larides (Walker) (Hymenoptera Platygasteridae). Quest’ultima specie viene segnalata per la prima volta in Italia. Asphondylia trabuti, nota gia come fitofago dei frutti di Solanum tuberosum, viene riportata per la prima volta in Italia e su Solanum nigrum; le larve sono gregarie, si sviluppano tra maggio e dicembre con un picco in primavera e si impupano all’interno dei frutti, completando il ciclo in circa due settimane. Sono state osservate almeno 5 generazioni per anno. In totale sono stati ottenuti 100 A. trabuti e 91 parassitoidi, 88 dei quali sono risultati Eurytoma dentata Mayr (Hymenoptera Eurytomidae), riportata per la prima volta come suo parassitoide, e 3 Pteromalidae. Parole chiave: Cystiphora sonchi, Asphondylia trabuti, Sonchus spp., Solanum nigrum.

Risk assessment of non-target effects of Closterocerus chamaeleon (Girault) parasitoid of the eucalypt gall maker Ophelimus maskelli (Ashmead) (Hymenoptera, Eulophidae)

The pre-release risk assessment, a recommended practice in biological control programmes, was carried out before introducing Closterocerus chamaeleon (Girault), a eulophid parasitoid of the eucalypt gall maker Ophelimus maskelli (Ashmead) (Hymenoptera, Eulophidae), in Sicily, Italy. We evaluated its host specificity in laboratory small arena no-choice tests on six non-target hosts, using O. maskelli as a control species. The non-target species fit with at least one of the following criteria: a) common geographical origin; b) ecological or behavioural affinities with the target host; c) concealed habit of the preimaginal stages; d) taxonomic affinity; e) taxonomic affinity with hosts of congeneric parasitoids of the candidate agent; and f) presence in Italy/Sicily. Closterocerus chamaeleon performed an oviposition sequence of 10 recognisable behaviours, always leading to parasitization when exposed to O. maskelli. The same behaviour sequence was carried out on the gall maker Leptocybe invasa Fisher et La Salle, the only non-target species living on Eucalyptus, but just until Step 6, i.e. until ovipositor extraction and insertion, and never until egg-laying. All of the other non-target hosts were ignored. Furthermore, the adult parasitoid longevity was assessed in three rearing conditions: 1) no food/no parasitisation permitted; 2) food/no parasitisation permitted; and 3) food provided after parasitisation. Adult wasp longevity was significantly higher in treatment 2 (21.1 days ± 4.1 SE) than in treatment 1 (3.6 days ± 0.5 SE) or 3 (3.8 days ± 0.6 SE). Laboratory tests carried out in this study on C. chamaeleon indicated high host selection ability, later confirmed by our post-release field data.

GENETIC VARIABILITY AND TAXONOMICAL CONSIDERATIONS ABOUT SIX SPECIES OF EUROPEAN CARDUELINE FINCHES (AVES, PASSERIFORMES)

Abstract Electrophoretic patterns of seven enzyme systems and two nonenzymatic proteins, albumin and haemoglobin, representing 13 loci, have been investigated in six species of cardueline finches with Palearctic distribution. A new locus, SOD-3, has been characterized in this subfamily. The two nonenzymatic proteins turned out to be the best genetic markers. From the analysis of the genetic distances it emerges that the mean values between species are higher than those reported for other groups of birds. However, the same results were obtained for other species of the same subfamily native to North America. In both cases this result is probably due to a classification that disagrees with the real cardueline phylogeny. In the present study, the attribution of the Greenfinch to the genus Carduelis raises the mean value of distance between species.