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New genus and species of Oriental Meligethinae with new observations on the genera Cryptarchopria and Kabakovia (Coleoptera: Nitidulidae)Josef JELÍNEKEur. J. Entomol. 97 (3): 413-418, 2000 | DOI: 10.14411/eje.2000.063 A new genus and species, Horakia kubani gen. n., sp. n., of Meligethinae from Thailand are described and compared with the closely related genus Cryptarchopria Jelínek. Cryptarchopria infima (Grouvelle) is recorded from the islands Ambon and Seram (Maluku, Indonesia), and its association with flowers of the palm Areca catechu L. is established for the first time. Diagnostic characters of the genus Kabakovia Kirejtshuk, 1979 are discussed, and Kabakovia latipes (Grouvelle, 1908) is recorded from Nepal for the first time. |
Dorso-abdominal scent glands and metathoracic evaporatoria in adults of central European Rhopalidae (Hemiptera: Heteroptera), with a discussion of phylogeny and higher systematicsJitka DAVIDOVÁ-VILÍMOVÁ, Markéta NEJEDLÁ, Carl W. SCHAEFEREur. J. Entomol. 97 (2): 213-221, 2000 | DOI: 10.14411/eje.2000.039 The reservoirs of dorso-abdominal scent glands and the occurrence of the metapleural scent gland evaporatoria in the adults of nine central European and one North American species in the family Rhopalidae (Hemiptera) were studied. All published data about the persistence of the dorso-abdominal scent glands in rhopalid adults are reviewed, and systematic and phylogenetic implications are derived from the patterns of variation. |
Fecundity and survival of Anagyrus kamali (Hymenoptera: Encyrtidae) under different feeding and storage temperature conditionsLaurent A. SAGARRA, Charles VINCENT, Robin K. STEWARTEur. J. Entomol. 97 (2): 177-181, 2000 | DOI: 10.14411/eje.2000.034 The parasitoid, Anagyrus kamali Moursi (Hymenoptera: Encyrtidae), has been recently introduced into the Caribbean as a biological control agent against the hibiscus mealybug (HMB), Maconellicoccus hirsutus Green (Homoptera: Pseudococcidae). Storage of A. kamali that is essential for its use in biological control did not affect the longevity of female and male parasitoids (40.3 ± 14.07 and 31.7 ± 9.57 days, respectively) when kept at 20 ± 2°C in absence of hosts and fed ad libitum with droplets of pure honey. At a storage temperature of 27 ± 2°C the longevity decreased by about 10 days. Fed females did not resorb eggs during the first two weeks of storage at 20 ± 2°. Parasitoid ovogenesis ceased when ovarioles/lateral oviducts were full. The lifetime fecundity was not significantly affected by a storage at 20 ± 2°C of up to 14 days. Foraging activities and oviposition were the main factors influencing the lifespan of female A. kamali. |
African-Arabian and Asian-Pacific "Mocis frugalis": Two distinct species (Lepidoptera: Noctuidae)Alberto ZILLIEur. J. Entomol. 97 (3): 419-426, 2000 | DOI: 10.14411/eje.2000.064 It is shown that under the name Mocis frugalis (F., 1775), considered to represent a widespread pest of graminaceous crops in the Eastern hemisphere and the Pacific, two species have been hitherto confused. Populations from Africa and Arabian Peninsula are described as Mocis proverai sp. n. The main characters which distinguish the African-Arabian M. proverai from M. frugalis of Asia and the Pacific are found in the genitalia, especially the configuration of the male vesica and female bursa copulatrix. |
Key life stages of two predatory ladybird species (Coleoptera: Coccinellidae)Pavel KINDLMANN, Hironori YASUDA, Satoru SATO, Katsuhiro SHINYAEur. J. Entomol. 97 (4): 495-499, 2000 | DOI: 10.14411/eje.2000.076 Development and survival of larvae of two predatory ladybird species, Harmonia axyridis (Pallas) and Coccinella septempunctata L. on hibiscus (Hibiscus syridis L.) trees was followed daily outdoors during four seasons. Data were analysed and stage-specific mortality in a stage-structured model was estimated using Manly's (1997) method. Subsequently, key factor analysis was used to determine the life stages in which the daily mortality was best correlated with the total mortality during larval life. Consistently with the results from the first two years, the larvae suffered the greatest mortality during the first and fourth instars. The k-values for these two instars were also best correlated with those for the whole larval life, especially in H. axyridis. |
Experimental hybridisation between Aphis grossulariae and Aphis triglochinis (Sternorrhyncha: Aphididae)Rimantas RAKAUSKASEur. J. Entomol. 97 (3): 377-386, 2000 | DOI: 10.14411/eje.2000.058 Aphis triglochinis and A. grossulariae clones from southern Poland produced fertile hybrid eggs under experimental conditions. Established hybrid clones expressed normal parthenogenetic reproduction but bisexual generations were obtained only in three hybrid clones out of twenty six. Fertile F1 hybrid eggs were obtained in one hybrid clone. Morphological and host-specificity features of A. grossulariae dominated in the majority of hybrid clones. The present results do not exclude the possibility of natural hybridisation of studied aphid species. Natural hybrids may be difficult to detect because of their "pure" morphological and host-specificity features. |
Ecological comparisons across geographical distributions: The thistle gall fly Urophora cardui (Diptera: Tephritidae) on two different Cirsium hostsMark FRENZEL, Sabine EBER, Stefan KLOTZ, Roland BRANDLEur. J. Entomol. 97 (2): 183-189, 2000 | DOI: 10.14411/eje.2000.035 Populations of the specialist gall-forming fly, Urophora cardui (Diptera: Tephritidae), were studied at the western and eastern margins of its distribution. In western Europe U. cardui attacks the creeping thistle Cirsium arvense, whereas in eastern Europe, in the Ural mountains, it attacks Cirsium setosum, a taxon closely related to C. arvense. Gall densities are high in the Ural mountains and can be predicted by environmental variables. Compared to galls on C. arvense, those on C. setosum are on average larger. This indicates better performance of U. cardui on C. setosum in terms of cell numbers per gall. Despite the wide distribution of U. cardui, the dominant parasitoids are the same at the western and eastern ends of its distribution and the interactions between parasitoids and the host are similar. In general, we suggest that the synchronisation between the host plant species, the phytophage and the parasitoids is an important factor in the spatial ecology and evolution of this food web. |
Effects of conspecific and heterospecific larval tracks on the oviposition behaviour of the predatory ladybird, Harmonia axyridis (Coleoptera: Coccinellidae)Hironori YASUDA, Takumi TAKAGI, Kazunobu KOGIEur. J. Entomol. 97 (4): 551-553, 2000 | DOI: 10.14411/eje.2000.085 The effect of the oviposition deterring pheromone (ODP) in the larval tracks of conspecific and heterospecific ladybirds on oviposition in Harmonia axyridis Pallas was studied in semi natural conditions. Gravid females of H. axyridis were deterred from ovipositing on plants contaminated with conspecific larval tracks, but not on those with heterospecific tracks. H. axyridis females spent significantly less time on plants contaminated with conspecific ODP than on those with heterospecific ODP. This behaviour may account for why fewer eggs were laid on plants contaminated with conspecific ODP. |
Effects of imidacloprid on Harmonia axyridis (Coleoptera: Coccinellidae) larval biology and locomotory behaviorCharles VINCENT, André FERRAN, Ludovic GUIGE, Jacques GAMBIER, Jacques BRUNEur. J. Entomol. 97 (4): 501-506, 2000 | DOI: 10.14411/eje.2000.077 The effects of imidacloprid on 1-day-old third instars of Harmonia axyridis were assessed by topical treatment and contact with treated glass plates in laboratory bioassays. When 5 µl of imidacloprid solutions were applied topically, the LD50 was 0.085 g/l per insect after 24 h. Contact with imidacloprid-treated plates had little effect on the number of third instars that became adults. Average duration of larval development was not significantly affected by duration of contact and imidacloprid concentrations. There were no significant differences in maximal larval weight, weight gain and day at maximum larval weight. There were significant differences in average weight gain per day (from third instar to prepupa) after treatments with different imidacloprid concentrations. A temporary knockdown effect was observed with higher concentrations and longer durations of contact with treated plates. Compared with untreated third instars, contact with imidacloprid-treated plates caused an increase in time spent (in seconds) on the glass plates resulting from an increase in number of stops (per second) and angular speed (degrees per second) and a decrease in linear speed, excluding stops (mm/second). The changes in locomotory behavior (i.e., duration of stay on untreated plate, number of stops and angular speed) lasted up to 24 h after contact with imidacloprid-treated plates. |
Application of ubiquitin SSCP analysis in taxonomic studies within the subgenus Orinocarabus (Coleoptera: Carabidae: Carabus)Dieter SEDLMAIR, Roland GERSTMEIER, Ralf EINSPANIEREur. J. Entomol. 97 (3): 387-394, 2000 | DOI: 10.14411/eje.2000.059 SSCP (single-strand conformation polymorphism) analyses of ubiquitin genes were used to investigate evolutionary relationships within the subgenus Orinocarabus of the genus Carabus. After SSCP electrophoresis of PCR-amplified ubiquitin copies, population-specific band patterns were obtained. Ubiquitin-SSCP-analyses of the six central European Orinocarabus species, including three subspecies and thirteen populations, resulted in a dendrogram that differed from that based on morphology. Phylogenetic analysis of mitochondrial DNA (mtDNA) did not support the SSCP dendrogram, but was in good accordance with the taxonomy based on morphological characters. The reason for the discrepancies seems to be evolutionary conservation of the ubiquitin genes. The time that elapsed since the evolution of the closely related Orinocarabus species is too short for concerted evolution of the ubiquitin genes. |
Galaicodytes caurelensis gen. n., sp. n., the first troglobitic species of Platynini (Coleoptera: Carabidae: Pterostichinae) from the western Palaearctic regionVicente M. ORTUÑO, José M. SALGADOEur. J. Entomol. 97 (2): 241-252, 2000 | DOI: 10.14411/eje.2000.041 This study describes Galaicodytes (gen. n.) caurelensis (sp. n.) which was captured in a limestone cave in the lower Cambric of NW Spain. It is the first known cave-dwelling Platynini in the western Palaearctic region and shows unique morphological adaptations to cave life. The taxonomic position is based on comprehensive character analysis, including external anatomical, male genitalic, and female genitalic and reproductive tract characters. Certain problems concerning its taxonomic position in relation to other genera are discussed and different ecologic and biogeographic aspects are analysed. |
Phenology and sex ratio of the parasitoids of a cereal leaf miner Chromatomyia fuscula (Diptera: Agromyzidae)Eline B. HAGVAR, Nina TRANDEM, Trond HOFSVANGEur. J. Entomol. 97 (3): 339-346, 2000 | DOI: 10.14411/eje.2000.051 The univoltine leaf miner Chromatomyia fuscula Zetterstedt is a Scandinavian cereal pest. We wanted to compare the phenology of C. fuscula in southern Norway with that of its most important natural enemies: 15 parasitoids of the families Eulophidae and Pteromalidae (Hymenoptera: Chalcidoidea). The use of two Malaise traps in an organically-grown spring barley field and its boundary through 6 seasons (1992-1997) also allowed us to compare these two habitats and to observe the effect of harvesting on the parasitoid activity without interference from pesticides. C. fuscula overwinters as an adult and oviposits in May/June. Few specimens of the next generation, emerging in the crop, were caught in the boundary traps, suggesting the fly hibernates elsewhere. In contrast, the F1 generation of the parasitoids was caught in considerable amounts both in the crop and boundary. The abundance of parasitoids was highest in July/August; in the crop it usually started decreasing well before harvesting; in the boundary it peaked two weeks or more after harvesting. The results suggest that many parasitoids (especially females) move from the crop to the boundary (or beyond) before harvesting. In both habitats parasitoid species richness usually increased until harvesting, and thereafter decreased. The pooled parasitoid female proportion was 0.36; in crop and boundary it was 0.30 and 0.66, respectively, and the majority of species had a higher proportion of females in the boundary than in the crop. The phenology of two of the most common parasitoids is presented: The pupal parasitoid Cyrtogaster vulgaris Walker (Pteromalidae) had a high activity in the boundary, also very early (females only) and late (both sexes) in the season. The larval parasitoid Diglyphus begini (Ashmead) (Eulophidae) was less active early and late in the season, and had a much smaller boundary activity than C. vulgaris. Both sexes were present throughout the season. The annual sex ratio of D. begini was density dependent, being highly male biased in the two years with highest catches. In C. vulgaris neither density nor habitat explained the sex ratio. D. begini probably overwinters inside the mine as a preadult, having one generation on C. fuscula in the crop and another one in an alternate host away from the habitats sampled here. C. vulgaris overwinters as fertilized females in the border habitat. |
Life history of Adalia bipunctata (Coleoptera: Coccinellidae) in JapanYasuyuki SAKURATANI, Yoshihito MATSUMOTO, Motoki OKA, Takahiko KUBO, Atsushi FUJII, Minatsu UOTANI, Toru TERAGUCHIEur. J. Entomol. 97 (4): 555-558, 2000 | DOI: 10.14411/eje.2000.086 Adalia bipunctata is a well-known predaceous ladybird distributed in Europe, Central Asia and North America. This species has not been recorded in Japan. Recently, we found this species in the Osaka Bay area in central Japan, and assume that it was imported with goods such as timber by ships. We studied the life history and the distribution in the Osaka Bay area since the initial discovery. The larvae and adults preyed on aphids (mainly, Periphyllus viridis) on trees such as Acer buergerianum and Rhaphiolepis umbellata. The over-wintered adults appeared in March and laid eggs. The adults emerged in spring, and were in the rolled leaves throughout the rest of the year. Thus, in Japan this ladybird is univoltine with long inactivity in adult. The life history of Japanese population of A. bipunctata differs considerably from other areas where populations are multivoltine. The developmental threshold was estimated to be 6.3°C and the sum of effective temperatures was 322.6 day-degrees for the period from egg to adult emergence. Predation on prepupae of A. bipunctata by the larvae of native species such as Harmonia axyridis was observed occasionally. |
Differences in the male calling songs of two sibling species of Cicada (Hemiptera: Cicadoidea) in GreecePaula C. SIMÕES, Michel BOULARD, Maria T. REBELO, Sakis DROSOPOULOS, Michael F. CLARIDGE, John C. MORGAN, José A. QUARTAUEur. J. Entomol. 97 (3): 437-440, 2000 | DOI: 10.14411/eje.2000.067 Cicada orni L. is one of the most abundant and common species of cicada in Greece. However, this species was not found during recent field work on the Greek islands of Samos and Ikaria. Instead, the very closely related C. mordoganensis Boulard was found practically everywhere on these islands. C. orni and C. mordoganensis are very closely related species which are morphologically very similar (sibling species), even the male genitalia, and the acoustic signals produced by males during courtship and pair formation have the same general pattern. In order to describe the acoustic signals produced by these sibling species, temporal and spectral analyses were made of the calling songs of the males and certain acoustic variables were measured. Based on the duration of echemes, the number of pulse units they contain, the intervals between echemes and the number of echemes per second, the song of C. mordoganensis is distinct from that of C. orni. Cluster analysis of the acoustic characteristics of C. mordoganensis from Samos and Ikaria and of C. orni from the Greek mainland (Dionysos, north of Athens) gave a clear and distinct separation of these species. |
Food remains in the guts of Coccinella septempunctata(Coleoptera: Coccinellidae) adults and larvaeTRILTSCH H.Eur. J. Entomol. 96 (4): 355-364, 1999 From 1994-1997 the food of Coccinella septempunctata L. was investigated on the basis of gut dissections of adults and larvae collected in the field. Additionally, the gut contents of adults fed under laboratory conditions were investigated. The likelihood of recovering different prey types during gut dissection was variable, which will be illustrated by presenting some common prey fragments. The food eaten by adult C. septempunctata throughout a year was studied at a locality in Berlin-Staaken. Ladybirds were collected from March 1994 until November 1997 in different crops and habitats on roughly a monthly basis. Aphid feeding was detectable from April until October. In May and June they were the most frequent food type. Fungal spores, in most cases the conidia of Alternaria spp., became most frequent in July. Additionally non-aphid arthropods were frequently preyed upon in July. A very common non-aphid prey item were thrips. Pollen was important in May and September. Comparing the food components of newly emerged adults with those of overwintered adults some remarkable differences were detected. In newly emerged adults non-aphid arthropods and fungal spores were much more frequent than in overwintered adults whereas aphids were less frequently found. The diet of adults and larvae was also investigated in June and July in cereal fields at two other localities, Northern Flaeming and Magdeburger Boerde. No difference in adult diet was found between the three localities. The composition of the larval diet was relatively similar to that of the adults. |
Larval morphology and biology of two species of Aphodius (Plagiogonus) from the Iberian Peninsula (Coleoptera: Scarabaeidae: Aphodiinae)José R. VERDÚ, Eduardo GALANTEEur. J. Entomol. 97 (3): 395-401, 2000 | DOI: 10.14411/eje.2000.060 The larval morphology of Aphodius (Plagiogonus) nanus Fairmaire, 1860 and A. (P.) arenarius (Olivier, 1789) are described and redescribed, respectively. The common characters of both species, and the specific diagnostic characters are provided and discussed. The most important morphological characters of the larvae of Plagiogonus Mulsant, 1842 are the longitudinal alignment of the anterior setae of the stipes, the spatulate form of the posterior-lateral setae of the glossae of the hypopharynx, the slight development of the anal lobe slit, the form of the epitorma of the epipharynx, the slight sclerotization of the pternotormae and the relative length of second antennal segment. A key to the larvae of both species of Plagiogonus is presented along with life history data and the preferred food of these species. This study shows that A. arenarius and A. nanus feeding habits are closer to saprophagy than to coprophagy. |
A south east Asian pest species newly recorded from Europe: Thrips parvispinus (Thysanoptera: Thripidae), its confused identity and potential quarantine significanceLaurence A. MOUND, Dominique W. COLLINSEur. J. Entomol. 97 (2): 197-200, 2000 | DOI: 10.14411/eje.2000.037 The south east Asian pest thrips, Thrips parvispinus is recorded breeding in Europe for the first time, damaging Gardenia plants in Greece. Morphological variation in this species from various Asian countries is recorded and compared to the type specimens. As a result Isoneurothrips jenseni Karny, 1925 and Thrips (Isoneurothrips) taiwanus Takahashi, 1936 are placed as synonyms of Thrips parvispinus (Karny, 1922). In contrast, Thrips compressicornis (Sakimura), a species from the Marquesa Islands of the Pacific that has previously been associated with these taxa, represents a very different species. The quarantine significance of T. parvispinus is emphasised. |
Revision of the genus Macroscytus (Heteroptera: Cydnidae) in Madagascar and adjacent islands, with description of four new speciesLIS J.A.Eur. J. Entomol. 96 (4): 427-437, 1999 A revision of species of the genus Macroscytus Fieber distributed in Madagascar and adjacent islands is presented. Four previously known species [M. fryeri Distant, M. lobatus Signoret, M. madagascariensis (Signoret), M. privignus Horváth] are redescribed, and lectotypes are designated for three of them. Four new species (M. mayottensis sp. n., M. simulans sp. n., M. tamatavei sp. n., and M. viettei sp. n.) are described and compared with their congeners. A key to all species of the genus known from Madagascar and adjacent islands is also provided. |
Book Review: Poluzhestkokrylye Nasekomye (Heteroptera) Sibiri.STYS P.Eur. J. Entomol. 95 (1): 26, 1998 Vinokurov N.N. & Kanyukova E.V.: Poluzhestkokrylye Nasekomye (Heteroptera) Sibiri (Heteroptera of Siberia). Nauka Novosibirsk, 1995, 238 pp. (in Russian). |
Cytogenetic analysis of some aradid species (Heteroptera: Aradidae)GROZEVA S.Eur. J. Entomol. 94 (3): 421-424, 1997 Known sex chromosome mechanisms in Aradidae are XX : XY or compound X(XnY). The present paper adds data obtained from studying testes of adults and stage IV and V larvae of four aradid species. The number of chromosomes and their behaviour during spermatogenesis (in Aradinae for the first time) were documented and illustrated: Aradus cinnamomeus Panter -2n = 35 (32 + X1X2Y); Aradus corticalis corticalis (L.) -2n = 28 (26 + XY); Aradus conspiculus Herrich-Schaffer 2n = 28 (26 + XY); Aneurus avenius Dufour -2n = 27 (24 + X1X2Y). Mechanisms which could have played a role in karyotype evolution in the family are discussed in the context of this study and data from literature. |
Are behavioural changes in parasitised aphids a protection against hyperparasitism?MüLLER C.B., VöLKL W., GODFRAY H.C.J.Eur. J. Entomol. 94 (2): 221-234, 1997 Parasitised aphids often leave the aphid colony before mummification. It has been suggested that this behaviour is an example of host manipulation by the primary aphidiid parasitoid to reduce the risk of hyperparasitism after mummy formation. Mummification site and hyperparasitism risk are surveyed in 16 species of aphid. Mummification away from the colony was not associated with reduced hyperparasitism. In ant-attended species, and in species with well developed parasitoid defence behaviour (such as kicking), mummies formed within the colony tended to suffer less hyperparasitism. In laboratory experiments, two hymenopteran ectohyperparasitoids, Dendrocerus carpenteri (Curtis) (Megaspilidae) and Asaphes vulgaris (Walker) (Pteromalidae), were more successful attacking parasitised aphids [Uroleucon jaceae (L.) (Aphididae)] when the mummies were outside the colony, not surrounded by living aphids. |
Autosomal recessive mutations affecting body colour in Pyrrhocoris apterus (Hemiptera: Pyrrhocoridae)SLAMA K.Eur. J. Entomol. 95 (1): 17-26, 1998 Genetic characteristics of the first three mutants found in P. apterus L.; white (w/w) 1965, yellow (y/y) 1966 and melanotic (m/m) 1973 have been described in detail. Exact Mendelian proportions of 1 : 1 and 3 : 1 in all standard test crosses and absence of sexual linkage revealed that each of these mutations was inherited as a single autosomal recessive gene. The dihybrid and trihybrid crosses showed that the w gene is epistatic over y. The absence of linkage shows that each of the described mutant genes is situated on a different chromosome. During 30 years of sustained rearings of P. apterus, the white (w/w) and yellow (y/y) mutants never originated de novo, whereas the melanotic (m/m) mutants originated independently from the macropterous strain three times. Triple recessive (w y m) white melanotic strain has been maintained and used for some genetic investigations for over 20 years. |
Reproduction of Aphelinus albipodus (Hymenoptera: Aphelinidae) on Russian wheat aphid (Hemiptera: Aphididae) hostsBERNAL J.S., WAGGONER M., GONZALEZ D.Eur. J. Entomol. 94 (1): 83-96, 1997 Reproduction in Aphelinus albipodus (Hayat & Fatima) from China on Diuraphis noxia (Mordvilko) hosts was studied in the laboratory. Studies were conducted at three constant temperatures, 10.0, 21.1, and 26.7°C (± 1.0°C), 14L : 10D photoperiod, and 50-70% R.H. The longevity of both males and females was greatest at 10.0°C (26.0 and 41.5 d, respectively); differences in longevity were not significant (p > 0.05) between 21.1 and 26.7°C in both sexes (males 13.1 vs. 10.0 d, females 20.9 vs. 16.4 d, respectively). Fecundity was greater at 26.7 (294.7 ± 27.6 mummies) and 21.1°C (214.8 ± 33.5 mummies) than at 10.0°C (569 ± 11.7 mummies), but was not significantly different (p > 0.05) between the former two temperatures. Aphelinus albipodus did not successfully develop to adulthood at 10°C, thus rm and Ro values were zero, and Tc (generation time) could not be estimated. At 21.1°C, rm = 0.188, Ro = 68.9, and Tc = 23.9 d; those values were 0.288, 67.4, and 15.2 d, respectively, at 26.7°C. The offspring sex ratio (females) was male-biased at all three temperatures: 0.364 ± 0.061 at 10.0°C, 0.437 ± 0.029 at 21.1°C, and 0.341 ± 0.002 at 26.7°C. Moreover, daily offspring sex ratio decreased with the age of the female parent at all three temperatures (p < 0.05). A pre-oviposition period of 1.5 d was observed in A. albipodus at 10° C, and female offspring were not produced during the first 7.5 d of adult life of mated females. The limited number of ovarian eggs, 6.5 ± 2.5, in newly emerged females (< 6 h old) together with their fecundity schedule indicated synovigeny in A. albipodus. Results are discussed in relation to the colonization in North America of A. albipodus for biological control of D. noxia. |
Effect of host plant on body size of Frankliniella occidentalis (Thysanoptera: Thripidae) and its correlation with reproductive capacityDE KOGEL W.J.*, BOSCO D., VAN DER HOEK M., MOLLEMA C.Eur. J. Entomol. 96 (4): 365-368, 1999 The effect of different host plants on Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) body size was investigated. Thrips from three different populations, from the Netherlands, Italy, and USA, achieved greater body sizes when reared on cucumber than on bean. The same thrips grew larger when reared on susceptible than on resistant cucumber. On the latter, reproduction was reduced, suggesting that smaller thrips have a lower reproduction. However, no evidence was found for a correlation between size and reproduction in experiments with thrips from four different populations, from the Netherlands, New Zealand, France, and USA that differed significantly in body size. Also when individual thrips from the four populations were tested, there was no correlation between size and reproduction. It is concluded that resistant cucumber affects both size and reproduction of F. occidentalis. However, lower reproduction in general is not associated with smaller body size. |
Host spatial pattern influences induction of parasitization by Trichogramma (Hymenoptera: Trichogrammatidae)VOINOVICH N.D., UMAROVA T.Y., REZNIK S.Y.*Eur. J. Entomol. 96 (4): 369-373, 1999 The influence of host intrapatch spatial distribution on parasitoid host acceptance behavior was investigated with Trichogramma principium parasitizing eggs of grain moth, Sitotroga cerealella. Single females were placed in Petri dishes, each containing 60 host eggs arranged either as a compact patch or partitioned into 60 or 12 clusters each consisting of 1 or 5 eggs, respectively. Partitioned patches provoked parasitization more often than compact patches. The percentage of ovipositing females (i.e., females parasitizing at least one of 60 host eggs) increased with the number of clusters, while it was independent of the intercluster distance over intervals of 2.5-15 mm. The mean number of eggs parasitized by ovipositing females during 48 h was almost independent of the host egg spatial pattern. As a result, the rate of parasitization was higher when the hosts were sparsely distributed within a patch than when they were aggregated. |
Book Review: Hydraenidae (Coleoptera). World Catalogue of Insects. Vol. 1.BOUKAL D.S.Eur. J. Entomol. 96 (4): 450, 1999 Hansen M. 1998: Hydraenidae (Coleoptera). World Catalogue of Insects. Vol. 1. Apollo Books, Stenstrup, 169 pp. |
Diversity and abundance of insect herbivores collected on Castanopsis acuminatissima (Fagaceae) in New Guinea: Relationships with leaf production and surrounding vegetationBASSET Y.Eur. J. Entomol. 96 (4): 381-391, 1999 Insect herbivores were collected from Castanopsis acuminatissima (Fagaceae) at Wau, Papua New Guinea, by beating the foliage of 15 trees during four one-month sampling periods, each representing different leaf-flush events. The association of leaf-chewing beetles with C. acuminatissima was verified with feeding trials. Of 59 species of leaf-chewing beetles that were collected, 36 species could be used in feeding trials. Only 9 of these species fed on C. acuminatissima. A further 27 beetle species were tested in feeding trials but did not feed. Of these, 7 were specialists feeding on other tree species within the surrounding vegetation. Most beetle species collected from C. acuminatissima foliage were probably transient species, dispersing from other tree species. Path analyses showed that herbivore abundance during a particular sampling period was significantly influenced by rainfall, leaf flush of other conspecific trees and air temperature, but not so by the species richness of surrounding vegetation, number of surrounding conspecific trees and size (DBH) of trees sampled. The species richness of leaf-chewing beetles collected on particular study trees depended on that of the surrounding vegetation, thus supporting the hypothesis that most beetle species collected were transient. The abundance of insect herbivores on particular C. acuminatissima trees probably depends on a balance between the leaf flush of conspecific trees and that of the particular tree sampled. The results also emphasize the need to remove transient species in analyses of insect faunas of tropical trees, at the risk of analyzing species richness patterns derived from loosely defined "assemblages" of species. |
Stimulation of locomotion in Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) is wing-morph independent and correlated with lipid mobilization by adipokinetic hormoneSOCHA R.*, KODRIK D., ZEMEK R.Eur. J. Entomol. 96 (4): 459-461, 1999 The effects of 5 pmols of adipokinetic hormone (Lom-AKH-I) on both the locomotion and mobilization of lipids were studied in 10-day-old diapausing adult females of the short-winged (brachypterous) morph of Pyrrhocoris apterus (L.). The results revealed that AKH stimulation of locomotion in this bug is wing-morph independent. The stimulatory effect of AKH on locomotion was shown to be positively correlated with its effect on lipid mobilization. |
Genetic identity and relationship between four Anagrus species (Hymenoptera: Mymaridae) using RAPD analysisCHIAPPINI E.*, SORESSI L., FOGHER C., ZANIRATO M.Eur. J. Entomol. 96 (4): 393-400, 1999 Four species of Anagrus (A. breviphragma Soyka, A. incarnatus Haliday, A. fennicus Soyka and A. obscurus Foerster sensu Soyka), that live on Carex riparia Curtis (Cyperaceae) in uncultivated areas along the Po river in the Piacenza province in Italy were analysed using RAPD markers in order to investigate their genetic relationships. High levels of RAPD polymorphism were found in the genus Anagrus, which permitted the fingerprinting of the four species. Analysis of average genetic similarities within species and comparison with average values between species confirms that A. breviphragma, A. incarnatus, A. fennicus and A. obscurus represent four genetically distinct species. A dendrogram constructed from molecular data of single families clearly clustered the four species in different groups, their mutual position reflecting morphological and biological observations. |
Plumbagin and azadirachtin deplete hemolymph ecdysteroid levels and alter the activity profiles of two lysosomal enzymes in the fat body of Helicoverpa armigera (Lepidoptera: Noctuidae)JOSEPHRAJKUMAR A., SUBRAHMANYAM B.*, SRINIVASAN S.Eur. J. Entomol. 96 (4): 347-353, 1999 The profile of hemolymph ecdysteroid was studied in the gram pod borer, Helicoverpa armigera, during larval-pupal transformation. The changes closely correspond to the developmental events occurring at metamorphosis. Two insect growth regulators, plumbagin and azadirachtin, significantly depleted the content and altered the profile of ecdysteroids at crucial stages, when applied at ED50 doses. The activity profiles of two fat body lysosomal enzymes, acid phosphatase and b-galactosidase, were also significantly affected by the insect growth regulators. It is suggested that plumbagin and azadirachtin treatments primarily modify the ecdysteroid titer, which in turn leads to changes in lysosomal enzyme activity causing overt morphological abnormalities during the metamorphic molt. |



