New data on the larvae of the weevil genus Larinus Dejean, 1821 (Coleoptera,Curculionidae) from northeastern Turkey

Larvae of Larinus fucatus Faust, 1891, L. capsulatus Gültekin, 2008, and Larinus sp. aff. leuzeae Fabre, 1870 are described for the first time. The larvae differ in the pattern on the head capsule, in the shape of the endocarinal line, and in the chaetotaxy of the epicranium, frons, and segments of the body, as well as in the presence or absence of stemmata. A key to larvae of 11 Larinus species is provided.     

New species of the weevil subgenus Eunihus Rtt., genus Otiorhynchus germ. (Coleoptera, Curculionidae), from the Caucasus and Turkey

Otiorhynchus khatiparicus Davidian et Arzanov, sp. n. and O. meoticus Davidian et Arzanov, sp. n. are described in the subgenus Eunihus Reitter, which was not known from the Caucasus before. Both of the new species are very similar to O. rhilensis Stierlin from Bulgaria and O. uludagicus Magnano from NW Turkey.     

Susceptibility of strawberry cultivars to the vine weevil Otiorhynchus sulcatus (Coleoptera: Curculionidae)

Abstract 1 The feeding preference of vine weevil, Otiorhynchus sulcatus (Fabricius), adults for foliage from 21 commercial cultivars of strawberries is investigated using binary choice tests with leaf disks, using ‘Honeoye’ as a standard against which all other cultivars are compared. ‘Delmarvel’, ‘Idea’, ‘Lester’, ‘Primetime’ and ‘Seneca’ are not preferred. 2 Variation in leaf nitrogen content is correlated with feeding preference, but does not explain all the variation, because outliers exist for both preferred and nonpreferred cultivars. 3 Removal of leaf hairs with adhesive tape permits their role in deterrence to be evaluated. Eight of the 21 cultivars have deterrent leaf hairs. Paradoxically, some highly preferred cultivars (e.g. ‘Latestar’ and ‘Tristar’) have deterrent leaf hairs, and four of the five nonpreferred cultivars lack significantly deterrent leaf hairs. 4 The 21 tested cultivars do not differ in their suitability for vine weevil larval development. 5 Differences in cultivar susceptibility to vine weevil in the field may involve interactions between the palatability and nutritional value of foliage, which influence fecundity and egg placement, and the tolerance of strawberry plants to larval feeding, determined by root biomass. The nonpreference traits found in the foliage of commercial cultivars of strawberry are present by chance. Accordingly, further selective breeding to enhance strawberry varietal tolerance to vine weevils may be possible.     

Contribution to the weevil fauna (Coleoptera,Curculionoidea) of Turkey

37 species of the weevil families Brentidae, Apionidae, Nanophyidae, Dryophthoridae, Erirhinidae, and Curculionidae are recorded for Turkey or for the Asian part of the country, most of them, for the first time. Some of the species are also newly recorded for other countries.     

Larval morphology of the weevil genus Ceutorhynchus (Coleoptera, Curculionidae) from Middle Asia

Larvae of three species of the weevil genus Ceutorhynchus (C. subtilirostris Schultze., C. viator Faust, and C. setosellus Voss) are described from Middle Asia for the first time. The larvae differ in the shape of frons, structure of the labrum, and chaetotaxy of the epicranium, frons, and lacinia. A key to the species described is given.     

New species of the weevil genus <Emphasis Type="Italic">Sitona</Emphasis> Germ. (Coleoptera,Curculionidae) from Transcaucasia and Northeastern Turkey

New species of the weevil genus Sitona Germ. are described: Sitona transcaucasicus sp. n. from the highlands of the Republic of Nakhichevan (Azerbaijan), S. davidiani sp. n. from the highlands of Southern Daghestan (Russia), Republic of Nakhichevan, and Northeastern Turkey, and S. abchasicus sp. n. from subalpine and alpine belts of Abkhazia and southeasternmost Krasnodar Territory (Russia).     

A review of the biology and control of the vine weevil, Otiorhynchus sulcatus (Coleoptera: Curculionidae)

At the turn of the century, damage by Otiorhynchus sulcatus was sporadic and limited to small areas. Increasing horticultural intensification and the adoption of husbandry techniques favourable to the weevil, such as the use of polythene mulches, increased its pest status. The development of the early inorganic pesticides reduced the number of serious outbreaks of this pest and weevil control was further improved by the development of the persistent organochlorine insecticides in the 1940's. The banning of a number of the more persistent insecticides over recent years has now left the horticultural industry in a very vulnerable position. O. sulcatus is now a pest on a range of horticultural crops throughout the temperate regions of the world. Infestations are most common in Europe (where it originated) and the USA, and nearly 150 plants species have been identified as potential hosts to O. sulcatus. Damage is most frequently caused by the root feeding larval stage. Populations as low as one larva plant can kill sensitive species such as Cyclamen. Severe damage by the leaf feeding adults is less common, although low levels of damage or contamination by adults may be unacceptable in certain situations. There is one generation a year. Oviposition by the flightless parthenogenetic females occurs over the summer months with oviposition rates of c. 500 and 1200 eggs adult^-1for outdoor and laboratory populations, respectively. O. sulcatus mainly overwinters as larvae, although significant numbers of adults may survive in areas where winter temperatures are not too severe. A number of natural enemies, such as hedgehogs, frogs and predatory beetles, help to maintain O. sulcatus populations at a low level in natural environments, but they are less successful in intensive horticultural systems where persistent chemicals have been heavily relied on to maintain the population below the economic threshold level. Increasing environmental concern is now forcing growers to consider new pest control strategies. Controlled release formulations of non-persistent products, such as fonofos and chlorpyrifos, have shown potential as control agents for O. sulcatus larvae. Biological control agents, such as insect parasitic nematodes, have been developed commercially and new microbial control agents are in the process of development. Most of the new control products are directed towards control of O. sulcatus larvae. Adult vine weevils are nocturnal and a much more difficult target for the new control agents. It is likely that an integrated approach to pest control will be required to maintain O. sulcatus populations below their economic threshold level.     

Speciation in the sub-Antarctic weevil genus Dusmoecetes Jeannel (Coleoptera: Curculionidae)

Relatively few instances of sympatric speciation have been reported in the literature, and both theoretical and empirical studies of this mode of speciation remain controversial. Recently, a model of sympatric speciation less restrictive than earlier ones has been proposed. This study presents a hypothetical speciation scenario, based on current observations, which seems to be consistent with the new model. Two morphologically similar, though ecologically separated, species are identified in the Dusmoecetes similis (C. O. Waterhouse) species complex on Marion Island (46° 54'S, 37° 45'E), based on a study of the morphology, biology and ecology of the group. Differences between the demands placed on angiosperm- and bryophyte-feeding members of the complex, and the differing demands of bryophyte and angiosperm-dominated communities, coupled with low vagility and a high degree of assortative mating, suggest that a sympatric model can be used to explain speciation in this genus, which probably occurred within the last 10,000 years. Differences between Dusmoecetes marioni Jeannel and D. Similis (Waterhouse) are discussed, and a lectotype designated for the latter species.     

Effects of a novel microsporidium on the black vine weevil, Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae)

A newly discovered microsporidium infecting the black vine weevil, Otiorhynchus sulcatus (F.) (Coleoptera: Curculionidae), provisionally placed in the genus Canningia, was studied to determine its impact on O. sulcatus. O. sulcatus populations from several locations were sampled and evaluated for microsporidiosis. A very low prevalence of the disease was observed in all locations surveyed (<3.0%). Laboratory studies were conducted by orally exposing both larvae and adults of O. sulcatus to varying concentrations of Canningia sp. spores. Larval bioassays at a variety of dosages (0, 10, etc.) were performed to evaluate pathogen infectivity, larval survival and growth. Adult bioassays (dosages: 0, 10, etc.) were performed to evaluate longevity, fecundity and mechanisms of vertical pathogen transmission. Larvae and adults were infected in all spore treatments. Larval growth was significantly reduced at dosages above 10 spores/larva. Adults infected at all dosages experienced high levels of mortality and fecundity was reduced to zero. Greenhouse trials were performed to determine if larvae feeding in soil acquired infections when spores were topically applied as a drench application (0, 10⁵, 10⁶, 10⁷ spores/pot). Established larvae feeding on plant roots in pots developed infections when exposed to drench treatments of 10⁶ and 10⁷ spores/pot after 14-21 days. Canningia sp. is an acute pathogen of O. sulcatus infective to both larvae and adults. Topically applied spores also infected larvae feeding on roots in soilless potting media, suggesting the possibility of using this pathogen in a microbial control program.     

Biological control of the black vine weevil, Otiorhynchus sulcatus (Coleoptera: Curculionidae) with entomopathogenic nematodes (Nematoda: Rhabditida)

Trials conducted under glasshouse conditions showed that control of Otiorhynchus sulcatus larvae in strawberry plants can be effective using Steinernema carpocapsae and Heterorhabditis megidis, given that temperature and moisture extremes are avoided. In field experiments, the double line T-Tape® drip irrigation system performed better than the single line T-Tape® system, effectively distributing the nematodes along and across strawberry raised beds, and placing them close to the root zone where O. sulcatus larvae feed. As soil temperatures are satisfactory for nematode infectivity from late spring to early autumn, nematode applications were aimed at late instar larvae during spring, and early instar larvae during summer. Late summer field treatment with S. carpocapsae induced 49.5% reduction of the early instar larvae, and field application of the same nematode species in late spring resulted in 65% control of late instar larvae. In the same trial, spring application of H. megidis caused 26% mortality of late instar larvae of O. sulcatus.     

Sustainable control of black vine weevil larvae,Otiorhynchus sulcatus (Coleoptera: Curculionidae) with Heterorhabditis bacteriophora in strawberry

Efficacy, persistence and recovery of the nematode Heterorhabditis bacteriophora was tested in the laboratory after application of the nematode to strawberry roots by dipping. To mitigate nematode sedimentation and improve attachment to strawberry roots, carboxy-methyl-cellulose was added to the nematode solution. Mortality of black vine weevil Otiorhynchus sulcatus varied between 90 and 96% in the pot trials.     

Contribution to the knowledge of the weevil genus <Emphasis Type="Italic">Otiorhynchus</Emphasis> Germ. (Coleoptera,Curculionidae) from Turkmenistan and adjacent territories

Data on 15 species of the subgenus Pseudotiorhynchus Magnano, 2004 of the genus Otiorhynchus Germar, 1822 from Kazakhstan, Turkmenistan, and Iran are given. Otiorhynchus lukarevskayae Davidian, sp. n., O. karakalensis Davidian et Savitsky, sp. n., O. konstantini Davidian et Savitsky, sp. n., O. muratovi Savitsky et Davidian, sp. n., O. kopetdagicus Savitsky et Davidian, sp. n., and O. shakhensis Savitsky et Davidian, sp. n. from Turkmenistan, and O. khorasanus Savitsky et Davidian, sp. n. from Iran are described as new to science. A new synonymy is established: Pseudotiorhynchus Magnano, 2004 = Crassorhynchus Magnano, 2004, syn. n. Otiorhynchus iranensis Magnano, 2004 is transferred from the subgenus Protarammichnus Voss, 1960 to the subgenus Pseudotiorhynchus. Lectotype of O. conicirostris Stierlin, 1886 is designated. A key to 15 species of the subgenus Pseudotiorhynchus is given. The new subgenus Microhanibotus Savitsky et Davidian, subgen. n. is established for the new species O. ghilarovi Davidian et Savitsky, sp. n. from the Western Kopet Dagh in Turkmenistan. Microhanibotus subgen. n. is closely related to the subgenera Pseudotiorhynchus, Hanibotus Reitter, 1912 and Nubidanus Reitter, 1912.     

Geographical distribution of the weevil subfamily Ceutorhynchinae (Coleoptera, Curculionidae)

A brief general characteristic and review of distribution of the subfamily Ceutorhynchinae over zoogeographical realms are given, with an emphasis on the distribution within the Holarctic and Palaearctic. The potential of exploiting landscapes of all natural zones of the Holarctic by a low-rank taxon is exemplified by the Holarctic Ceutorhynchus cochleariae (Gyll.) species-group comprising ca. 20 species evenly distributed between the Palaearctic and Nearctic. Although neighboring with the powerful centers of tropical biota, the Holarctic fauna of the subfamily Ceutorhynchinae is formed mostly of endemic and subendemic genera which are especially abundant in the Palaearctic. This region possesses the most diversified generic and species composition of the fauna consisting of predominantly endemic and subendemic genera (in the Mediterranean and Saharo-Gobian regions, also of the highly diversified tribe Oxyonychini) up to its southern border. The existence of characteristic transitional faunas in the zones of contact of the Holarctic fauna with the faunas of the tropical regions in East Asia and Mexico is shown. These transitional faunas include a considerable number of endemic taxa of the genus and species groups. A conspicuous feature of the Palaearctic ceutorhynchine fauna is the rather numerous complex of the upland and high-latitude species.     

A review of the weevil genus Ptochus Schoenh. (Coleoptera, Curculionidae) of the fauna of Daghestan

A review of, and a key to seven species of the genus Ptochus Schoenherr from Daghestan are given. Five new species from inner Daghestan are described: P. gulnarae sp. n., P. obrieni sp. n., P. korotyaevi sp. n., P. davidiani sp. n., and P. avaricus sp. n. Ectmetaspidus daghestanicus Formánek, 1908 is transferred to Ptochus.     

Karyological investigations on seven weevil species (Coleoptera, Curculionidae)

Karyological studies were carried out on seven Palaearctic weevils. The following chromosome numbers were found in individual species, i.e. Otiorhynchus niger (F.), Phyllobius viridearis (Laich.), Phyllobius scutellaris Redt., Phyllobius calcaratus (F.), Polydrusus cervinus (L.), and Brachyderes incanus (L.) 2n = 22, n Male = 10 + Xyp, in Lixus elegantulus (Boh.) 2n = 22, n Male = 21 + Xyp. The heterochromosomes of all the examined species form, in the first meiotic metaphase, a typical parachute bivalent.     

A new genus and a new species of the weevil subfamily Hyperinae (Coleoptera,Curculionidae) from Western Tien Shan,Uzbekistan

A new monotypical genus Basilypera gen. n. with the type species B. tatyanae sp. n. is described from Angren Plateau in Western Tien Shan, Uzbekistan.     

Karyological notes on three weevil species from Armenia (Coleoptera, Curculionidae, Cleoninae)

Karyological studies were carried out on three Armenian weevil species from the subfamily Cleoninae. The following chromosome numbers were found in individual species: 2n = 38, n Male = 18 + Xyp in Menecleonus anxius (Gyllenhal, 1824), 2n = 40, n Male = 19 + Xyp in Conorhynchus nigrivittis (Pallas, 1781) and 2n = 44, n Male = 21 + Xyp in Lixus iridis Olivier, 1807. The heterochromosomes of all the examined species form, in the first meiotic metaphase, a typical parachute bivalent.     

A contribution to the knowledge of the weevils of the subgenus Nubidanus Rtt., allied to Otiorhynchus impexus Schh. (Coleoptera, Curculionidae)

Results of the investigation of the subgenus Nubidanus Rtt. (sensu Reitter) of the genus Otiorhynchus are reported. The impexus species-group of the subgenus Nubidanus comprises 5 species from the Caucasus: O. impexus, O. juvenilis, O. poricollis, O. jarpachlinus, and O. hajastani. Morphological diagnoses and detailed distribution patterns of the species are given. Lectotypes of O. poricollis and O. jarpachlinus are designated. A new synonymy is established: O. poricollis Schoenherr, 1832 = O. breviusculus Stierlin, 1875, syn. n. Variants of the genesis scenario of the impexus species-group in the eastern part of the Caucasus are discussed.